Mapping products of Titan's surface

USGS Publications Warehouse

Stephan, Katrin; Jaumann, Ralf; Karkoschka, Erich; Barnes, Jason W.; Tomasko, Martin G.; Turtle, Elizabeth P.; Le Corre, Lucille; Langhans, Mirjam; Le Mouelic, Stephane; Lorenz, Ralf D.; Perry, Jason; Brown, Robert H.; Lebreton, Jean-Pierre

2009-01-01

Remote sensing instruments aboard the Cassini spacecraft have been observed the surface of Titan globally in the infrared and radar wavelength ranges as well as locally by the Huygens instruments revealing a wealth of new morphological features indicating a geologically active surface. We present a summary of mapping products of Titan's surface derived from data of the remote sensing instruments onboard the Cassini spacecraft (ISS, VIMS, RADAR) as well as the Huygens probe (DISR) that were achieved during the nominal Cassini mission including an overview of Titan's recent nomenclature.

An Anomalous Force on the Map Spacecraft

NASA Technical Reports Server (NTRS)

Starin, Scott R.; ODonnell, James R., Jr.; Ward, David K.; Wollack, Edward J.; Bay, P. Michael; Fink, Dale R.; Bauer, Frank (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe (MAP) orbits the second Earth-Sun libration point (L2)-about 1.5 million kilometers outside Earth's orbit-mapping cosmic microwave background radiation. To achieve orbit near L2 on a small fuel budget, the MAP spacecraft needed to swing past the Moon for a gravity assist. Timing the lunar swing-by required MAP to travel in three high-eccentricity phasing loops with critical maneuvers at a minimum of two, but nominally all three, of the perigee passes. On the approach to the first perigee maneuver, MAP telemetry showed a considerable change in system angular momentum that threatened to cause on-board Failure Detection and Correction (FDC) to abort the critical maneuver. Fortunately, the system momentum did not reach the FDC limit; however, the MAP team did develop a contingency strategy should a stronger anomaly occur before or during subsequent perigee maneuvers, Simultaneously, members of the MAP team developed and tested various hypotheses for the cause of the anomalous force. The final hypothesis was that water was outgassing from the thermal blanketing and freezing to the cold side of the solar shield. As radiation from Earth warmed the cold side of the spacecraft, the uneven sublimation of frozen water created a torque on the spacecraft.

Mapping products of Titan's surface: Chapter 19

USGS Publications Warehouse

Stephan, Katrin; Jaumann, Ralf; Karkoschka, Erich; Kirk, Randolph L.; Barnes, Jason W.; Tomasko, Martin G.; Turtle, Elizabeth P.; Le Corre, Lucille; Langhans, Mirjam; Le Mouélic, Stéphane; Lorenz, Ralph D.; Perry, Jason; Brown, Robert; Lebreton, Jean-Pierre; Waite, J. Hunter

2010-01-01

Remote sensing instruments aboard the Cassini spacecraft have been observed the surface of Titan globally in the infrared and radar wavelength ranges as well as locally by the Huygens instruments revealing a wealth of new morphological features indicating a geologically active surface. We present a summary of mapping products of Titan's surface derived from data of the remote sensing instruments onboard the Cassini spacecraft (ISS, VIMS, RADAR) as well as the Huygens probe (DISR) that were achieved during the nominal Cassini mission including an overview of Titan's recent nomenclature.

Go Huygens!

NASA Image and Video Library

2005-01-11

This map illustrates the planned imaging coverage for the Descent Imager/Spectral Radiometer, onboard the European Space Agency's Huygens probe during the probe's descent toward Titan's surface on Jan. 14, 2005. The Descent Imager/Spectral Radiometer is one of two NASA instruments on the probe. The colored lines delineate regions that will be imaged at different resolutions as the probe descends. On each map, the site where Huygens is predicted to land is marked with a yellow dot. This area is in a boundary between dark and bright regions. This map was made from the images taken by the Cassini spacecraft cameras on Oct. 26, 2004, at image scales of 4 to 6 kilometers (2.5 to 3.7 miles) per pixel. The images were obtained using a narrow band filter centered at 938 nanometers -- a near-infrared wavelength (invisible to the human eye) at which light can penetrate Titan's atmosphere to reach the surface and return through the atmosphere to be detected by the camera. The images have been processed to enhance surface details. Only brightness variations on Titan's surface are seen; the illumination is such that there is no shading due to topographic variations. For about two hours, the probe will fall by parachute from an altitude of 160 kilometers (99 miles) to Titan's surface. During the descent the camera on the probe and five other science instruments will send data about the moon's atmosphere and surface back to the Cassini spacecraft for relay to Earth. The Descent Imager/Spectral Radiometer will take pictures as the probe slowly spins, and some these will be made into panoramic views of Titan's surface. This map shows the planned coverage by the medium- and high-resolution. PIA06173 shows expected coverage by the Descent Imager/Spectral Radiometer side-looking imager and two downward-looking imagers - one providing medium-resolution and the other high-resolution coverage. http://photojournal.jpl.nasa.gov/catalog/PIA06173

MAP Attitude Control System Design and Flight Performance

NASA Technical Reports Server (NTRS)

Andrews, S. F.; ODonnell, J. R.; Bauer, Frank H. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. To make a full-sky map of cosmic microwave background fluctuations, a combination fast spin and slow precession motion will be used that will cover the entire celestial sphere in six months. The spin rate should be an order of magnitude higher than the precession rate, and each rate should be tightly controlled. The sunline angle should be 22.5 +/- 0.25 deg. Sufficient attitude knowledge must be provided to yield instrument pointing to a standard deviation of 1.3 arc-minutes RSS three axes. In addition, the spacecraft must be able to acquire and hold the sunline at initial acquisition, and in the event of a failure. Finally. the spacecraft must be able to slew to the proper burn orientations and to the proper off-sunline attitude to start the compound spin. The design and flight performance of the Attitude Control System on MAP that meets these requirements will be discussed.

KSC01pd1176

NASA Image and Video Library

2001-06-19

KENNEDY SPACE CENTER, Fla. -- Workers at Launch Complex 17-B, Cape Canaveral Air Force Station, place protective covers around the Microwave Anisotropy Probe (MAP) spacecraft. Launch of MAP via a Boeing Delta II rocket is scheduled for June 30. The launch will place MAP into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The probe will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures

The Microwave Anisotropy Probe (MAP) Attitude Control System

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Andrews, Stephen F.; ODonnell, James R., Jr.; Ward, David K.; Ericsson, Aprille J.; Bauer, Frank H. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe mission is designed to produce a map of the cosmic microwave background radiation over the entire celestial sphere by executing a fast spin and a slow precession of its spin axis about the Sun line to obtain a highly interconnected set of measurements. The spacecraft attitude is sensed and controlled using an Inertial Reference Unit, two Autonomous Star Trackers, a Digital Sun Sensor, twelve Coarse Sun Sensors, three Reaction Wheel Assemblies, and a propulsion system. This paper describes the design of the attitude control system that carries out this mission and presents some early flight experience.

Stationkeeping Approach for the Microwave Anisotropy Probe (MAP)

NASA Technical Reports Server (NTRS)

Rohrbaugh, Dave; Schiff, Conrad

2002-01-01

The Microwave Anisotropy Probe was successfully launched on June 30, 2001 and placed into a Lissajous orbit about the L2 Sun-Earth-Moon libration point. However, the L2 libration point is unstable which necessitates occasional stationkeeping maneuvers in order to maintain the spacecraft s Lissajous orbit. Analyses were performed in order to develop a feasible L2 stationkeeping strategy for the MAP mission. The resulting strategy meets the allotted fuel budget, allowing for enough fuel to handle additional he1 taxes, while meeting the attitude requirements for the maneuvers. Results from the first two stationkeeping maneuvers are included.

The Microwave Anisotropy Probe (MAP) Mission

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Andrews, Stephen F.; ODonnell, James R., Jr.; Ward, David K.; Bauer, Frank H. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe mission is designed to produce a map of the cosmic microwave background radiation over the entire celestial sphere by executing a fast spin and a slow precession of its spin axis about the Sun line to obtain a highly interconnected set of measurements. The spacecraft attitude is sensed and controlled using an inertial reference unit, two star trackers, a digital sun sensor, twelve coarse sun sensors, three reaction wheel assemblies, and a propulsion system. This paper presents an overview of the design of the attitude control system to carry out this mission and presents some early flight experience.

The Microwave Anisotropy Probe (MAP) Mission

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Andrews, Stephen F.; ODonnell, James R., Jr.; Ward, David K.; Ericsson, Aprille J.; Bauer, Frank H. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe mission is designed to produce a map of the cosmic microwave background radiation over the entire celestial sphere by executing a fast spin and a slow precession of its spin axis about the Sun line to obtain a highly interconnected set of measurements. The spacecraft attitude is sensed and controlled using an Inertial Reference Unit, two Autonomous Star Trackers, a Digital Sun Sensor, twelve Coarse Sun Sensors, three Reaction Wheel Assemblies, and a propulsion system. This paper describes the design of the attitude control system that carries out this mission and presents some early flight experience.

An Anomalous External Force on the MAP Spacecraft

NASA Technical Reports Server (NTRS)

Starin, Scott R.; Bay, P. Michael; Wollack, Edward J.; Fink, Dale R.; Ward, David K.; ODonnell, James R., Jr.; Bauer, Frank H. (Technical Monitor)

2002-01-01

A common theme in discussions of the Microwave Anisotropy Probe (MAP) is the attainment of mission goals for minimal cost. One area of cost savings was a reduction in the fuel budget required. To reach orbit around the L2 notation point of the Earth-Sun system, the MAP spacecraft was guided very close to the Moon, allowing a gravity-assisted trajectory out to L2. In order to property time the lunar swing-by, MAP followed a trajectory of three-and-a-half highly elliptical phasing loops. At each perigee of this trajectory MAP executed a thruster maneuver to increase orbit velocity; maneuvers were required at one or both clothe first two perigees (called P1 and P2) and at the third and final perigee (P-final). The preference was for successful maneuvers at all three perigees because this scheme provided a small, additional fuel savings.

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NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- Photographers gather in the Spacecraft Assembly and Encapsulation Facility -2 for a media showing of the Microwave Anisotropy Probe (MAP). The MAP is mated to the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp1134

NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- Workers in the Spacecraft Assembly and Encapsulation Facility -2 prepare the Microwave Anisotropy Probe (MAP) for a media showing. The MAP is mated to the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp1133

NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- Workers in the Spacecraft Assembly and Encapsulation Facility -2 prepare the Microwave Anisotropy Probe (MAP) for a media showing. The MAP is mated to the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

A Two-Wheel Observing Mode for the MAP Spacecraft

NASA Technical Reports Server (NTRS)

Starin, Scott R.; ODonnell, James R., Jr.

2001-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE). Due to the MAP project's limited mass, power, and budget, a traditional reliability concept including fully redundant components was not feasible. The MAP design employs selective hardware redundancy, along with backup software modes and algorithms, to improve the odds of mission success. This paper describes the effort to develop a backup control mode, known as Observing II, that will allow the MAP science mission to continue in the event of a failure of one of its three reaction wheel assemblies. This backup science mode requires a change from MAP's nominal zero-momentum control system to a momentum-bias system. In this system, existing thruster-based control modes are used to establish a momentum bias about the sun line sufficient to spin the spacecraft up to the desired scan rate. Natural spacecraft dynamics exhibits spin and nutation similar to the nominal MAP science mode with different relative rotation rates, so the two reaction wheels are used to establish and maintain the desired nutation angle from the sun line. Detailed descriptions of the ObservingII control algorithm and simulation results will be presented, along with the operational considerations of performing the rest of MAP's necessary functions with only two wheels.

KSC-01pp1123

NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- In the Spacecraft Assembly and Encapsulation Facility -2, the Microwave Anisotropy Probe (MAP) is lifted for moving to the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

Galileo to Jupiter: Probing the Planet and Mapping Its Moons

NASA Technical Reports Server (NTRS)

1979-01-01

The first project to use the space shuttle as an interplanetary launch vehicle, the Galileo mission is designed to obtain information about the origin and evolution of the solar system by studying large-scale phenomena on Jupiter and its satellites. Aimed towards Mars to obtain gravity assist, the orbiting spacecraft will deploy a probe, which penetrating the Jovian atmosphere, will transmit data for approximately an hour. The spacecraft itself will inspect the atmospheres, ionospheres, and surfaces of Ganymede, Io, Europa, and Callisto, as well as determine their magnetic and gravitational properties. The experiments to be conducted and their scientific objectives are described. Known facts about the Jovian system are reviewed.

KSC-01pp1038

NASA Image and Video Library

2001-05-29

KENNEDY SPACE CENTER, FLA. -- On Launch Complex 17-B, Cape Canaveral Air Force Station, the second stage of a Boeing Delta 7425-10 rocket is lifted into position as preparations to launch NASA's Microwave Anisotropy Probe (MAP) on June 30 continue. The launch will place MAP into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission.; The probe will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. The probe is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp1036

NASA Image and Video Library

2001-05-29

On Launch Complex 17-B, Cape Canaveral Air Force Station, the second stage of a Boeing Delta 7425-10 rocket is lifted into position as preparations to launch NASA's Microwave Anisotropy Probe (MAP) on June 30 continue. The launch will place MAP into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission.; The probe will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. The probe is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp1037

NASA Image and Video Library

2001-05-29

On Launch Complex 17-B, Cape Canaveral Air Force Station, the second stage of a Boeing Delta 7425-10 rocket is lifted into position as preparations to launch NASA's Microwave Anisotropy Probe (MAP) on June 30 continue. The launch will place MAP into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission.; The probe will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. The probe is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0942

NASA Image and Video Library

2001-04-21

KENNEDY SPACE CENTER, FLA. -- Workers in the Spacecraft Assembly and Encapsulation Facility 2 place an antenna on the Microwave Anisotropy Probe (MAP). Several other milestones must be completed while MAP is at SAEF-2, including solar array installation, solar array deployment and illumination testing, a spacecraft comprehensive performance test, fueling with hydrazine propellant and a spin balance test. MAP will then be ready for integration with the solid propellant Payload Assist Module upper stage booster. MAP is scheduled for launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0944

NASA Image and Video Library

2001-04-23

KENNEDY SPACE CENTER, FLA. -- In the Spacecraft Assembly and Encapsulation Facility 2, the Microwave Anisotropy Probe (MAP) undergoes testing and checkout. Several milestones must be completed while MAP is at SAEF-2, including antenna and solar array installation, solar array deployment and illumination testing, a spacecraft comprehensive performance test, fueling with hydrazine propellant and a spin balance test. MAP will then be ready for integration with the solid propellant Payload Assist Module upper stage booster. MAP is scheduled for launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0939

NASA Image and Video Library

2001-04-21

KENNEDY SPACE CENTER, FLA. -- The Microwave Anisotropy Probe (MAP) is worked on in the Spacecraft Assembly and Encapsulation Facility 2. Several milestones must be completed while MAP is at SAEF-2, including antenna installations, solar array installation, solar array deployment and illumination testing, a spacecraft comprehensive performance test, fueling with hydrazine propellant and a spin balance test. MAP will then be ready for integration with the solid propellant Payload Assist Module upper stage booster. MAP is scheduled for launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

Power Control and Monitoring Requirements for Thermal Vacuum/Thermal Balance Testing of the MAP Observatory

NASA Technical Reports Server (NTRS)

Johnson, Chris; Hinkle, R. Kenneth (Technical Monitor)

2002-01-01

The specific heater control requirements for the thermal vacuum and thermal balance testing of the Microwave Anisotropy Probe (MAP) Observatory at the Goddard Space Flight Center (GSFC) in Greenbelt, Maryland are described. The testing was conducted in the 10m wide x 18.3m high Space Environment Simulator (SES) Thermal Vacuum Facility. The MAP thermal testing required accurate quantification of spacecraft and fixture power levels while minimizing heater electrical emissions. The special requirements of the MAP test necessitated construction of five (5) new heater racks.

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NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- In the Spacecraft Assembly and Encapsulation Facility -2, the Microwave Anisotropy Probe (MAP), suspended by a crane, crosses the facility to the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

Microwave Anisotrophy Probe Launch and Early Operations

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Andrews, Stephen F.; Starin, Scott R.; Ward, David K.; Bauer, Frank H. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe (MAP), a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE), was launched from the Kennedy Space Center at 19:46:46 UTC on June 30, 2001. The powered flight and separation from the Delta II appeared to go as designed, with the launch placing MAP well within sigma launch dispersion and with less than 7 Nms of tip-off momentum. Because of this relatively low momentum, MAP was able to acquire the sun within only 15 minutes with a battery state of charge of 94%. After MAP's successful launch, a six week period of in-orbit checkout and orbit maneuvers followed. The dual purpose of the in-orbit checkout period was to validate the correct performance of all of MAP's systems and, from the attitude control system (ACS) point of view, to calibrate the performance of the spacecraft ACS sensors and actuators to maximize system performance. In addition to the checkout activities performed by the MAP team, the other critical activity taking place during the first six weeks after launch were a series of orbit maneuvers necessary to get the spacecraft from its launch orbit out to its desired orbit about L2, the second Earth-Sun Lagrange point. As MAP continues its standard operations, its ACS design is meeting all of its requirements to successfully complete the mission. This paper will describe the launch and early operations summarized above in greater detail, and show the performance of the attitude control and attitude determination system versus its requirements. Additionally, some of the unexpected events that occurred during this period will be discussed, including two events which dropped the spacecraft into its Safehold Mode and the presence of an "anomalous force" observed during each of the perigee orbit maneuvers that had the potential to cause these critical maneuvers to be prematurely aborted.

MAP Attitude Control System Design and Analysis

NASA Technical Reports Server (NTRS)

Andrews, S. F.; Campbell, C. E.; Ericsson-Jackson, A. J.; Markley, F. L.; ODonnell, J. R., Jr.

1997-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The MAP spacecraft will perform its mission in a Lissajous orbit around the Earth-Sun L(sub 2) Lagrange point to suppress potential instrument disturbances. To make a full-sky map of cosmic microwave background fluctuations, a combination fast spin and slow precession motion will be used. MAP requires a propulsion system to reach L(sub 2), to unload system momentum, and to perform stationkeeping maneuvers once at L(sub 2). A minimum hardware, power and thermal safe control mode must also be provided. Sufficient attitude knowledge must be provided to yield instrument pointing to a standard deviation of 1.8 arc-minutes. The short development time and tight budgets require a new way of designing, simulating, and analyzing the Attitude Control System (ACS). This paper presents the design and analysis of the control system to meet these requirements.

KSC-01pp1172

NASA Image and Video Library

2001-06-19

KENNEDY SPACE CENTER, Fla. -- The Microwave Anisotropy Probe (MAP) spacecraft is lifted up the gantry on Launch Complex 17-B, Cape Canaveral Air Force Station, where it will undergo final testing and installation of the payload fairing. Launch of MAP via a Boeing Delta II rocket is scheduled for June 30. The launch will place MAP into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The probe will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures

KSC-01pp0940

NASA Image and Video Library

2001-04-21

KENNEDY SPACE CENTER, FLA. -- Workers in the Spacecraft Assembly and Encapsulation Facility 2 stand by while the Microwave Anisotropy Probe (MAP) is lifted to place it on a workstand. Several milestones must be completed while MAP is at SAEF-2, including antenna installations, solar array installation, solar array deployment and illumination testing, a spacecraft comprehensive performance test, fueling with hydrazine propellant and a spin balance test. MAP will then be ready for integration with the solid propellant Payload Assist Module upper stage booster. MAP is scheduled for launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

Backup Attitude Control Algorithms for the MAP Spacecraft

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Andrews, Stephen F.; Ericsson-Jackson, Aprille J.; Flatley, Thomas W.; Ward, David K.; Bay, P. Michael

1999-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The MAP spacecraft will perform its mission, studying the early origins of the universe, in a Lissajous orbit around the Earth-Sun L(sub 2) Lagrange point. Due to limited mass, power, and financial resources, a traditional reliability concept involving fully redundant components was not feasible. This paper will discuss the redundancy philosophy used on MAP, describe the hardware redundancy selected (and why), and present backup modes and algorithms that were designed in lieu of additional attitude control hardware redundancy to improve the odds of mission success. Three of these modes have been implemented in the spacecraft flight software. The first onboard mode allows the MAP Kalman filter to be used with digital sun sensor (DSS) derived rates, in case of the failure of one of MAP's two two-axis inertial reference units. Similarly, the second onboard mode allows a star tracker only mode, using attitude and derived rate from one or both of MAP's star trackers for onboard attitude determination and control. The last backup mode onboard allows a sun-line angle offset to be commanded that will allow solar radiation pressure to be used for momentum management and orbit stationkeeping. In addition to the backup modes implemented on the spacecraft, two backup algorithms have been developed in the event of less likely contingencies. One of these is an algorithm for implementing an alternative scan pattern to MAP's nominal dual-spin science mode using only one or two reaction wheels and thrusters. Finally, an algorithm has been developed that uses thruster one shots while in science mode for momentum management. This algorithm has been developed in case system momentum builds up faster than anticipated, to allow adequate momentum management while minimizing interruptions to science. In this paper, each mode and algorithm will be discussed, and simulation results presented.

Ionizing radiation environment for the TOMS mission

NASA Technical Reports Server (NTRS)

Lauriente, M.; Maloy, J. O.; Vampola, A. L.

1992-01-01

The Total Ozone Mapping Spectrometer (TOMS) will fly on several different spacecraft, each having an orbit which is approximately polar and 800-980 km in altitude. A description is given of the computer-based tools used for characterizing the spacecraft interactions with the ionizing radiation environment in orbit and the susceptibility requirements for ionizing radiation compatibility. The peak flux from the model was used to derive the expected radiation-induced noise in the South Atlantic Anomaly for the new TOMS instruments intended to fly on Advanced Earth Observatory System and Earth Probe.

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NASA Image and Video Library

2001-04-20

KENNEDY SPACE CENTER, FLA. -- Inside the Spacecraft Assembly and Encapsulation Facility 2, a covered Microwave Anisotropy Probe (MAP) satellite is revealed after removal of the container (far right). MAP will undergo testing in the SAEF-2 before its scheduled launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission (3 months transit, 24 months observing). The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0883

NASA Image and Video Library

2001-04-20

KENNEDY SPACE CENTER, FLA. -- The Microwave Anisotropy Probe (MAP) satellite arrives at KSC’s Spacecraft Assembly and Encapsulation Facility 2. MAP will undergo testing in the SAEF-2 before its scheduled launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission (3 months transit, 24 months observing). The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0884

NASA Image and Video Library

2001-04-20

KENNEDY SPACE CENTER, FLA. -- The container with the Microwave Anisotropy Probe (MAP) satellite inside is backed into the Spacecraft Assembly and Encapsulation Facility 2. MAP will undergo testing in the SAEF-2 before its scheduled launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission (3 months transit, 24 months observing). The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-01pp0885

NASA Image and Video Library

2001-04-20

KENNEDY SPACE CENTER, FLA. -- The container with the Microwave Anisotropy Probe (MAP) satellite inside moves into the Spacecraft Assembly and Encapsulation Facility 2. MAP will undergo testing in the SAEF-2 before its scheduled launch June 30 from Cape Canaveral Air Force Station on a Delta II rocket into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission (3 months transit, 24 months observing). The MAP instrument consists of a set of passively cooled microwave radiometers with 1.4x 1.6-meter diameter primary reflectors to provide the desired angular resolution. MAP measures small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

Galileo Outreach Compilation

NASA Technical Reports Server (NTRS)

1998-01-01

This NASA JPL (Jet Propulsion Laboratory) video production is a compilation of the best short movies and computer simulation/animations of the Galileo spacecraft's journey to Jupiter. A limited number of actual shots are presented of Jupiter and its natural satellites. Most of the video is comprised of computer animations of the spacecraft's trajectory, encounters with the Galilean satellites Io, Europa and Ganymede, as well as their atmospheric and surface structures. Computer animations of plasma wave observations of Ganymede's magnetosphere, a surface gravity map of Io, the Galileo/Io flyby, the Galileo space probe orbit insertion around Jupiter, and actual shots of Jupiter's Great Red Spot are presented. Panoramic views of our Earth (from orbit) and moon (from orbit) as seen from Galileo as well as actual footage of the Space Shuttle/Galileo liftoff and Galileo's space probe separation are also included.

MIDEX Advanced Modular and Distributed Spacecraft Avionics Architecture

NASA Technical Reports Server (NTRS)

Ruffa, John A.; Castell, Karen; Flatley, Thomas; Lin, Michael

1998-01-01

MIDEX (Medium Class Explorer) is the newest line in NASA's Explorer spacecraft development program. As part of the MIDEX charter, the MIDEX spacecraft development team has developed a new modular, distributed, and scaleable spacecraft architecture that pioneers new spaceflight technologies and implementation approaches, all designed to reduce overall spacecraft cost while increasing overall functional capability. This resultant "plug and play" system dramatically decreases the complexity and duration of spacecraft integration and test, providing a basic framework that supports spacecraft modularity and scalability for missions of varying size and complexity. Together, these subsystems form a modular, flexible avionics suite that can be modified and expanded to support low-end and very high-end mission requirements with a minimum of redesign, as well as allowing a smooth, continuous infusion of new technologies as they are developed without redesigning the system. This overall approach has the net benefit of allowing a greater portion of the overall mission budget to be allocated to mission science instead of a spacecraft bus. The MIDEX scaleable architecture is currently being manufactured and tested for use on the Microwave Anisotropy Probe (MAP), an inhouse program at GSFC.

The MAP Spacecraft Angular State Estimation After Sensor Failure

NASA Technical Reports Server (NTRS)

Bar-Itzhack, Itzhack Y.; Harman, Richard R.

2003-01-01

This work describes two algorithms for computing the angular rate and attitude in case of a gyro and a Star Tracker failure in the Microwave Anisotropy Probe (MAP) satellite, which was placed in the L2 parking point from where it collects data to determine the origin of the universe. The nature of the problem is described, two algorithms are suggested, an observability study is carried out and real MAP data are used to determine the merit of the algorithms. It is shown that one of the algorithms yields a good estimate of the rates but not of the attitude whereas the other algorithm yields a good estimate of the rate as well as two of the three attitude angles. The estimation of the third angle depends on the initial state estimate. There is a contradiction between this result and the outcome of the observability analysis. An explanation of this contradiction is given in the paper. Although this work treats a particular spacecraft, the conclusions have a far reaching consequence.

The Effect of Sensor Failure on the Attitude and Rate Estimation of MAP Spacecraft

NASA Technical Reports Server (NTRS)

Bar-Itzhack, Itzhack Y.; Harman, Richard R.

2003-01-01

This work describes two algorithms for computing the angular rate and attitude in case of a gyro and a Star Tracker failure in the Microwave Anisotropy Probe (MAP) satellite, which was placed in the L2 parking point from where it collects data to determine the origin of the universe. The nature of the problem is described, two algorithms are suggested, an observability study is carried out and real MAP data are used to determine the merit of the algorithms. It is shown that one of the algorithms yields a good estimate of the rates but not of the attitude whereas the other algorithm yields a good estimate of the rate as well as two of the three attitude angles. The estimation of the third angle depends on the initial state estimate. There is a contradiction between this result and the outcome of the observability analysis. An explanation of this contradiction is given in the paper. Although this work treats a particular spacecraft, its conclusions are more general.

Using Automation to Improve the Flight Software Testing Process

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Andrews, Stephen F.; Morgenstern, Wendy M.; Bartholomew, Maureen O.; McComas, David C.; Bauer, Frank H. (Technical Monitor)

2001-01-01

One of the critical phases in the development of a spacecraft attitude control system (ACS) is the testing of its flight software. The testing (and test verification) of ACS flight software requires a mix of skills involving software, attitude control, data manipulation, and analysis. The process of analyzing and verifying flight software test results often creates a bottleneck which dictates the speed at which flight software verification can be conducted. In the development of the Microwave Anisotropy Probe (MAP) spacecraft ACS subsystem, an integrated design environment was used that included a MAP high fidelity (HiFi) simulation, a central database of spacecraft parameters, a script language for numeric and string processing, and plotting capability. In this integrated environment, it was possible to automate many of the steps involved in flight software testing, making the entire process more efficient and thorough than on previous missions. In this paper, we will compare the testing process used on MAP to that used on previous missions. The software tools that were developed to automate testing and test verification will be discussed, including the ability to import and process test data, synchronize test data and automatically generate HiFi script files used for test verification, and an automated capability for generating comparison plots. A summary of the perceived benefits of applying these test methods on MAP will be given. Finally, the paper will conclude with a discussion of re-use of the tools and techniques presented, and the ongoing effort to apply them to flight software testing of the Triana spacecraft ACS subsystem.

Using Automation to Improve the Flight Software Testing Process

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Morgenstern, Wendy M.; Bartholomew, Maureen O.

2001-01-01

One of the critical phases in the development of a spacecraft attitude control system (ACS) is the testing of its flight software. The testing (and test verification) of ACS flight software requires a mix of skills involving software, knowledge of attitude control, and attitude control hardware, data manipulation, and analysis. The process of analyzing and verifying flight software test results often creates a bottleneck which dictates the speed at which flight software verification can be conducted. In the development of the Microwave Anisotropy Probe (MAP) spacecraft ACS subsystem, an integrated design environment was used that included a MAP high fidelity (HiFi) simulation, a central database of spacecraft parameters, a script language for numeric and string processing, and plotting capability. In this integrated environment, it was possible to automate many of the steps involved in flight software testing, making the entire process more efficient and thorough than on previous missions. In this paper, we will compare the testing process used on MAP to that used on other missions. The software tools that were developed to automate testing and test verification will be discussed, including the ability to import and process test data, synchronize test data and automatically generate HiFi script files used for test verification, and an automated capability for generating comparison plots. A summary of the benefits of applying these test methods on MAP will be given. Finally, the paper will conclude with a discussion of re-use of the tools and techniques presented, and the ongoing effort to apply them to flight software testing of the Triana spacecraft ACS subsystem.

System design of the Pioneer Venus spacecraft. Volume 11: Launch vehicle utilization

NASA Technical Reports Server (NTRS)

Varga, R. J.

1973-01-01

A summary of the spacecraft descriptions; the probe bus, large probe, small probe, and orbiter is presented. The highlights on the designs of the Atlas/Centaur spacecraft as compared to the corresponding Thor/Delta spacecraft designs are contained. A comparison is made of the two Atlas/Centaur spacecraft for reference. The major differences are the replacement of the probes of the forward end of the probe bus with the mechanically despun antenna of the orbiter and the replacement of the bicone antenna on the aft end with the orbit insertion motor. The cross sections of the large and small probes are compared. The major features of each probe are described. The Thor/Delta and Atlas/Centaur designs for the probe bus and orbiter are analyzed. The usable spacecraft mass for the Atlas/Centaur is roughly twice that for the Thor/Delta if the Type I trajectory is assumed. It is somewhat less for the Type II trajectory in the designated launch years. This additional mass capability leads to cost savings in many areas which are described.

Apparatus and method of capturing an orbiting spacecraft

NASA Technical Reports Server (NTRS)

Harwell, William D. (Inventor); Gardner, Dale A. (Inventor)

1987-01-01

Apparatus and a method of capturing an orbiting spacecraft by attaching a grapple fixture are discussed. A probe is inserted into an opening, such as a rocket nozzle, in the spacecraft until a stop on the prove mechanism contacts the spacecraft. A lever is actuated releasing a spring loaded rod which moves axially along the probe removing a covering sleeve to expose spring loaded toffle fingers which pivot open engaging the side of the opening. The probe is shortened and tensioned by turning a screw thread, pressing the fingers inside of the opening to compress the spacecraft between the toggle fingers and the stop. A grapple fixture attached to the probe, which is thus secured to the spacecraft, is engaged by appropriate retrieval means such as a remote manipulator arm.

KSC-05pd2592

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, clean-suit garbed workers secure the fairing sections around the New Horizons spacecraft for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-06pd0009

NASA Image and Video Library

2006-01-11

KENNEDY SPACE CENTER, FLA. - In the Vertical Integration Facility on Launch Complex 41, Cape Canaveral Air Force Station, Hal Weaver, New Horizons project scientist with the Johns Hopkins University Applied Physics Laboratory, signs the fairing enclosing the New Horizons spacecraft. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2590

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections move into place around the New Horizons spacecraft for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2591

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections close in around the New Horizons spacecraft to encapsulate it. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2589

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the New Horizons spacecraft waits for encapsulation within the fairing sections waiting nearby. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

MAP stability, design, and analysis

NASA Technical Reports Server (NTRS)

Ericsson-Jackson, A. J.; Andrews, S. F.; O'Donnell, J. R., Jr.; Markley, F. L.

1998-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The design and analysis of the MAP attitude control system (ACS) have been refined since work previously reported. The full spacecraft and instrument flexible model was developed in NASTRAN, and the resulting flexible modes were plotted and reduced with the Modal Significance Analysis Package (MSAP). The reduced-order model was used to perform the linear stability analysis for each control mode, the results of which are presented in this paper. Although MAP is going to a relatively disturbance-free Lissajous orbit around the Earth-Sun L(2) Lagrange point, a detailed disturbance-torque analysis is required because there are only a small number of opportunities for momentum unloading each year. Environmental torques, including solar pressure at L(2), aerodynamic and gravity gradient during phasing-loop orbits, were calculated and simulated. Thruster plume impingement torques that could affect the performance of the thruster modes were estimated and simulated, and a simple model of fuel slosh was derived to model its effect on the motion of the spacecraft. In addition, a thruster mode linear impulse controller was developed to meet the accuracy requirements of the phasing loop burns. A dynamic attitude error limiter was added to improve the performance of the ACS during large attitude slews. The result of this analysis is a stable ACS subsystem that meets all of the mission's requirements.

The Attitude Control System for the Wilkinson Microwave Anisotropy Probe

NASA Technical Reports Server (NTRS)

Markley, F. Landis; Andrews, Stephen F.; ODonnell, James R., Jr.; Ward, David K.

2003-01-01

The Wilkinson Microwave Anisotropy Probe mission produces a map of the cosmic microwave background radiation over the entire celestial sphere by executing a fast spin and a slow precession of its spin axis about the Sun line to obtain a highly interconnected set of measurements. The spacecraft attitude is sensed and controlled using an inertial reference unit, two star trackers, a digital sun sensor, twelve coarse sun sensors, three reaction wheel assemblies, and a propulsion system. Sufficient attitude knowledge is provided to yield instrument pointing to a standard deviation (l sigma) of 1.3 arc-minutes per axis. In addition, the spacecraft acquires and holds the sunline at initial acquisition and in the event of a failure, and slews to the proper orbit adjust orientations and to the proper off-sunline attitude to start the compound spin. This paper presents an overview of the design of the attitude control system to carry out this mission and presents some early flight experience.

KSC-01pp1125

NASA Image and Video Library

2001-06-15

KENNEDY SPACE CENTER, Fla. -- The Microwave Anisotropy Probe (MAP) is lowered onto the upper stage of the Boeing Delta II rocket. The rocket is scheduled to launch the MAP instrument June 30 into a lunar-assisted trajectory to the Sun-Earth for a 27-month mission. MAP will measure small fluctuations in the temperature of the cosmic microwave background radiation to an accuracy of one millionth of a degree. These measurements should reveal the size, matter content, age, geometry and fate of the universe. They will also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures. The MAP instrument will be continuously shaded from the Sun, Earth, and Moon by the spacecraft. It is a product of Goddard Space Flight Center in partnership with Princeton University

KSC-05pd2410

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2415

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, technicians prepare the New Horizons spacecraft for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2414

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is ready for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2411

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, technicians prepare the New Horizons spacecraft for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2413

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is being prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Closed Loop Software Control of the MIDEX Power System

NASA Technical Reports Server (NTRS)

Castell, Karen; Hernandez-Pellerano, Amri; Wismer, Margaret

1998-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on to the Differential Microwave Radiometer (DMR) instrument on the Cosmic Background Explorer (COBE) spacecraft. The design and analysis of the MAP attitude control system (ACS) have been refined since work previously reported. The full spacecraft and instrument flexible model was developed in NASTRAN, and the resulting flexible modes were plotted and reduced with the Modal Significance Analysis Package (MSAP). The reduced-order model was used to perform the linear stability analysis for each control mode, the results of which are presented in this paper. Although MAP is going to a relatively disturbance-free Lissajous orbit around the Earth-Sun L2 Lagrange point, a detailed disturbance-torque analysis is required because there are only a small number of opportunities for momentum unloading each year. Environmental torques, including solar pressure at L2, and aerodynamic and gravity gradient during phasing-loop orbits, were calculated and simulated. A simple model of fuel slosh was derived to model its effect on the motion of the spacecraft. In addition, a thruster mode linear impulse controller was developed to meet the accuracy requirements of the phasing loop burns. A dynamic attitude error limiter was added to improve the performance of the ACS during large attitude slews. The result of this analysis is a stable ACS subsystem that meets all of the mission's requirements.

KSC-05pd2588

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections are ready to be moved in place around the New Horizons spacecraft (in center) for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2587

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, clean-suit garbed workers prepare the first fairing section (in the background) that will encapsulate the New Horizons spacecraft at left for flight. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

The RF Probe: providing space situational awareness through broad-spectrum detection and characterization

NASA Astrophysics Data System (ADS)

Zenick, Raymond; Kohlhepp, Kimberly; Partch, Russell

2004-09-01

AeroAstro's patented RF Probe is a system designed to address the needs of spacecraft developers and operators interested in measuring and analyzing near-field RF emissions emanating from a nearby spacecraft of interest. The RF Probe consists of an intelligent spectrum analyzer with digital signal processing capabilities combined with a calibrated, wide-bandwidth antenna and RF front end that covers the 50 kHz to 18 GHz spectrum. It is capable of acquiring signal level and signal vector information, classifying signals, assessing the quality of a satellite"s transponders, and characterizing near-field electromagnetic emissions. The RF Probe is intended for either incorporation as part of a suite of spacecraft sensors, or as a stand-alone sensor on spacecraft or other platforms such as Unmanned Aerial Vehicles (UAVs). The RF Probe was initially conceived as a tool to detect and aid in diagnosis of malfunctions in a spacecraft of interest. However, the utility of the RF Probe goes far beyond this initial concept, spanning a wide range of military applications. Most importantly, the RF Probe can provide space situational awareness for critical on-orbit assets by detecting externally induced RF fields, aiding in protection against potentially devastating attacks.

Development of a Two-Wheel Contingency Mode for the MAP Spacecraft

NASA Technical Reports Server (NTRS)

Starin, Scott R.; ODonnell, James R., Jr.; Bauer, Frank (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on mission to the Cosmic Background Explorer (COBE), and is currently collecting data from its orbit near the second Sun-Earth libration point. Due to limited mass, power, and financial resources, a traditional reliability concept including fully redundant components was not feasible for MAP. Instead, the MAP design employs selective hardware redundancy in tandem with contingency software modes and algorithms to improve the odds of mission success. One direction for such improvement has been the development of a two-wheel backup control strategy. This strategy would allow MAP to position itself for maneuvers and collect science data should one of its three reaction wheels fail. Along with operational considerations, the strategy includes three new control algorithms. These algorithms would use the remaining attitude control actuators-thrusters and two reaction wheels-in ways that achieve control goals while minimizing adverse impacts on the functionality of other subsystems and software.

A new and innovative use of the thermal knife and Kevlar cord components in a restraint and release system

NASA Astrophysics Data System (ADS)

Stewart, Alphonso C.

2001-09-01

A Kevlar cord and two thermal knives are key components in the Solar Array Restraint and Release System (SARRS) on the Microwave Anisotropy Probe (MAP) spacecraft at NASA's Goddard Space Flight Center. The SARRS uses a 25-foot (7.62 m) length Kevlar cord that encircles the spacecraft and secures the solar panels in stowed configuration for launch. Once in orbit, one of two redundantly configured thermal knives severs the Kevlar cord and permits the panels to deploy. The purpose of this paper is to present the details of the design, development test results, and the various innovations that were created during the development of this novel use of the thermal knife and Kevlar cord.

A New and Innovative Use of the Thermal Knife and Kevlar Cord Components in a Restraint and Release System

NASA Technical Reports Server (NTRS)

Stewart, Alphonso; Brodeur, Stephen J. (Technical Monitor)

2001-01-01

A Kevlar cord and two thermal knives are key components in the Soar Array Restraint and Release System (SARRS) on the Microwave Anisotropy Probe (MAP) spacecraft at NASA's Goddard Space Flight Center. The SARRS uses a 25-foot (7.62 m) length Kevlar cord that encircles the spacecraft and secures the solar panels in stowed configuration for launch. Once in orbit, one of two redundantly configured thermal knives severs the Kevlar cord and permits the panels to deploy. The purpose of this paper is to present the details of the design, development test results, and the various innovations that were created during the development of this novel use of the thermal knife and Kevlar cord.

VLA Will Receive Galileo Probe Signals To Measure Jupiter's Winds

NASA Astrophysics Data System (ADS)

1995-11-01

Socorro, NM -- When the Galileo Probe becomes the first spacecraft to enter the atmosphere of Jupiter on Dec. 7, a New Mexico radio telescope will be watching. In a technical feat thought impossible when Galileo was launched in 1989, the National Science Foundation's Very Large Array (VLA) will record the faint radio signal from the probe to help scientists measure the giant planet's winds. The VLA observations will dramatically improve estimates of Jupiter's wind speeds and complement other measurements studying the climate of Jupiter. The Galileo probe will transmit information to the main spacecraft as it descends toward a searing death under tremendous heat in Jupiter's lower atmosphere. The main spacecraft will later relay the probe's data to Earth. No Earth-based reception of the probe's radio signals was planned originally. The probe's antenna will be pointed at the main spacecraft, not the Earth. However, in 1991, Robert Preston and William Folkner of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, CA, were discussing Earth-based reception of data from a similar probe under design for a planned mission to Saturn. "I thought, why not do this for Galileo," Folkner said. "They were planning to build this capability into the spacecraft for Saturn," Folkner explained, "and they thought it couldn't be done with the Galileo spacecraft already enroute to Jupiter. I didn't know it couldn't be done, so I worked it out and found that we could do it." According to Preston and Folkner's calculations, the direct reception of the probe's signals by the VLA and a similar radio telescope in Australia will make the measurement of Jupiter's winds ten times more precise as long as the probe radio signal can be detected. In addition, the direct reception also greatly improves scientists' knowledge of the probe's position as it enters the Jovian atmosphere. This will allow more effective use of the measurements of the probe radio signal by the main spacecraft to determine atmospheric properties. The VLA observations will record the shift in frequency of the probe's radio signal as Jupiter's winds buffet the probe. This Doppler shift in frequency will allow scientists to calculate the wind speeds. Scientists expect the 746-pound probe to send information about Jupiter's atmosphere for up to 75 minutes during its parachute-slowed descent. Preston and Folkner, who are working with Jose Navarro of the National Radio Astronomy Observatory (NRAO) in Socorro, NM, expect to receive the probe's signals with the VLA for the first 20 or 30 minutes of the descent. The technical difficulties in directly receiving the probe's signal are challenging. The probe has only a 25-watt radio transmitter. The probe's directional antenna is aimed at the main Galileo spacecraft, nearly 90 degrees away from the direction of the Earth. This effectively reduces the power to 7 watts or less toward the Earth. At Jupiter, the probe is more than half a billion miles distant from Earth. Only a large radio telescope is capable of receiving this faint signal, more than 100,000 times weaker than the faintest signal a home FM radio can pick up. Even using a radio telescope as large as the VLA, the scientists may have to wait for the main Galileo spacecraft to send the probe's data back to Earth before they can recover the signals they recorded. With the relayed data in hand, they can "reconstruct" the probe's radio signal and use that reconstructed signal to help their computers find the weak recorded signal on the VLA tapes. A preliminary relay of the probe's data from the main spacecraft is planned in December. During its descent, the Galileo probe will send information about the chemical composition of Jupiter's atmosphere at different altitudes. It is expected to encounter winds of up to 200 m.p.h.

The NASA Solar Probe mission - In situ determination of interplanetary out-of-the ecliptic and near-solar dust environments

NASA Technical Reports Server (NTRS)

Tsurutani, Bruce T.; Randolph, James E.

1991-01-01

The NASA Solar Probe mission will be one of the most exciting dust missions ever flown and will lead to a revolutionary advance in our understanding of dust within our solar system. Solar Probe will map the dust environment from the orbit of Jupiter (5 AU), to within 4 solar radii of the sun's center. The region between 0.3 AU and 4 Rs has never been visited before, so the ten days that the spacecraft spends during each (of the two) orbit is purely exploratory in nature. Solar Probe will also reach heliographic latitudes as high as about 15 to 28 deg above (below) the ecliptic on its trajectory inbound (outbound) to (from) the sun. This, in addition to the ESA/NASA Ulysses mission, will help determine the out-of-the-ecliptic dust environment. A post-perihelion burn will reduce the satellite orbital period to 2.5 years about the sun. A possible extended mission would allow data reception for two more revolutions, mapping out a complete solar cycle. Because the near-solar dust environment is not well understood (or is controversial at best), and it is very important to have better knowledge of the dust environment to protect Solar Probe from high velocity dust hits, we urgently request the scientific community to obtain further measurements of the nearsolar dust properties.

Probe interface design consideration. [for interplanetary spacecraft missions

NASA Technical Reports Server (NTRS)

Casani, E. K.

1974-01-01

Interface design between a probe and a spacecraft requires not only technical considerations but also management planning and mission analysis interactions. Two further aspects of importance are the flyby versus the probe trade-off, and the relay link design and data handling optimization.

System design of the Pioneer Venus spacecraft. Volume 9: Attitude control/mechanisms subsystems studies

NASA Technical Reports Server (NTRS)

Neil, A. L.

1973-01-01

The Pioneer Venus mission study was conducted for a probe spacecraft and an orbiter spacecraft to be launched by either a Thor/Delta or an Atlas/Centaur launch vehicle. Both spacecraft are spin stabilized. The spin speed is controlled by ground commands to as low as 5 rpm for science instrument scanning on the orbiter and as high as 71 rpm for small probes released from the probe bus. A major objective in the design of the attitude control and mechanism subsystem (ACMS) was to provide, in the interest of costs, maximum commonality of the elements between the probe bus and orbiter spacecraft configurations. This design study was made considering the use of either launch vehicle. The basic functional requirements of the ACMS are derived from spin axis pointing and spin speed control requirements implicit in the acquisition, cruise, encounter and orbital phases of the Pioneer Venus missions.

Electrostatic-probe measurements of plasma parameters for two reentry flight experiments at 25000 feet per second

NASA Technical Reports Server (NTRS)

Jones, W. L., Jr.; Cross, A. E.

1972-01-01

Unique plasma diagnostic measurements at high altitudes from two geometrically similar blunt body reentry spacecraft using electrostatic probe rakes are presented. The probes measured the positive ion density profiles (shape and magnitude) during the two flights. The probe measurements were made at eight discrete points (1 cm to 7 cm) from the vehicle surface in the aft flow field of the spacecraft over the altitude range of 85.3 to 53.3 km (280,000 to 175,000 ft) with measured densities of 10 to the 8th power to 10 to the 12th power electrons/cu cm, respectively. Maximum reentry velocity for each spacecraft was approximately 7620 meters/second (25,000 ft/sec). In the first flight experiment, water was periodically injected into a flow field which was contaminated by ablation products from the spacecraft nose region. The nonablative nose of the second spacecraft thereby minimized flow field contamination. Comparisons of the probe measured density profiles with theoretical calculations are presented with discussion as to the probable cause of significant disagreement. Also discussed are the correlation of probe measurements with vehicle angle of attack motions and the good high altitude agreement between electron densities inferred from the probe measurements, VHF antenna measurements, and microwave reflectometer diagnostic measurements.

High-spatial-resolution electron density measurement by Langmuir probe for multi-point observations using tiny spacecraft

NASA Astrophysics Data System (ADS)

Hoang, H.; Røed, K.; Bekkeng, T. A.; Trondsen, E.; Clausen, L. B. N.; Miloch, W. J.; Moen, J. I.

2017-11-01

A method for evaluating electron density using a single fixed-bias Langmuir probe is presented. The technique allows for high-spatio-temporal resolution electron density measurements, which can be effectively carried out by tiny spacecraft for multi-point observations in the ionosphere. The results are compared with the multi-needle Langmuir probe system, which is a scientific instrument developed at the University of Oslo comprising four fixed-bias cylindrical probes that allow small-scale plasma density structures to be characterized in the ionosphere. The technique proposed in this paper can comply with the requirements of future small-sized spacecraft, where the cost-effectiveness, limited space available on the craft, low power consumption and capacity for data-links need to be addressed. The first experimental results in both the plasma laboratory and space confirm the efficiency of the new approach. Moreover, detailed analyses on two challenging issues when deploying the DC Langmuir probe on a tiny spacecraft, which are the limited conductive area of the spacecraft and probe surface contamination, are presented in the paper. It is demonstrated that the limited conductive area, depending on applications, can either be of no concern for the experiment or can be resolved by mitigation methods. Surface contamination has a small impact on the performance of the developed probe.

Sunny Side of a Comet

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1: Temperature Map

This image composite shows comet Tempel 1 in visible (left) and infrared (right) light (figure 1). The infrared picture highlights the warm, or sunlit, side of the comet, where NASA's Deep Impact probe later hit. These data were acquired about six minutes before impact. The visible image was taken by the medium-resolution camera on the mission's flyby spacecraft, and the infrared data were acquired by the flyby craft's infrared spectrometer.

The energetic particle environment of the solar probe mission: As estimated by the participants of the Solar Probe Environment Workshop

NASA Technical Reports Server (NTRS)

Neugebauer, M.; Fisk, L. A.; Gold, R. E.; Lin, R. P.; Newkirk, G.; Simpson, J. A.; Vanhollebeke, M. A. I.

1978-01-01

NASA's long-range plan for the study of solar-terrestrial relations includes a Solar Probe Mission in which a spacecraft is placed in an eccentric orbit with perihelion at four solar radii. Possible radiation damage to the spacecraft and mission from energetic particles was discussed at a Solar Probe Environment Workshop which concluded that it would be unlikely for such a spacecraft to suffer fatal radiation damage, although a severe problem exists in limiting the neutron flux from a radioactive power supply enough to allow solar neutrons to be detected.

KSC-05pd2412

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility is NASA’s New Horizons spacecraft that is scheduled to be launched to Pluto and its moon Charon in January 2006. Seen here is the Radio Science Experiment (REX) that will measure atmospheric composition and temperature. The spacecraft is being prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Electrostatic Structure and Double-Probe Performance in Tenuous Plasmas

NASA Astrophysics Data System (ADS)

Cully, C. M.; Ergun, R. E.

2006-12-01

Many in-situ plasma instruments are affected by the local electrostatic structure surrounding the spacecraft. In order to better understand this structure, we have developed a fully 3-dimensional self-consistent model that uses realistic spacecraft geometry, including thin (<1 mm) wires and long (>100m) booms, with open boundary conditions. One of the more surprising results is that in tenuous plasmas, the charge on the booms can dominate over the charge on the spacecraft body. For instruments such as electric field double probes and boom-mounted low-energy particle detectors, this challenges the existing paradigm: long booms do not allow the probes to escape the spacecraft potential. Instead, the potential structure simply expands as the boom is deployed. We then apply our model to the double-probe Electric Field and Waves (EFW) instruments on Cluster, and predict the magnitudes of the main error sources. The overall error budget is consistent with experiment, and the model yields some additional interesting insights. We show that the charge in the photoelectron cloud is relatively unimportant, and that the spacecraft potential is typically underestimated by about 20% by double-probe experiments.

Synoptic maps constructed from brightness observations of Thomson scattering by heliospheric electrons

NASA Technical Reports Server (NTRS)

Hick, P.; Jackson, B.; Schwenn, R.

1991-01-01

Observations of the Thomson scattering brightness by electrons in the inner heliosphere provide a means of probing the heliospheric electron distributions. An extensive data base of Thomson scattering observations, stretching over many years, is available from the zodiacal light photometers on board the two Helios spacecraft. A survey of these data is in progress, presenting these scattering intensities in the form of synoptic maps for successive Carrington rotations. The Thomson scattering maps reflect conditions at typically several tenths of an astronomical unit from the sun. Some representative examples from the survey in comparison with other solar/heliospheric data, such as in situ observations of the Helios plasma experiment and synoptic maps constructed from magnetic field, H alpha and K-coronameter data are presented. The comparison will provide some information about the extension of solar surface features into the inner heliosphere.

GRAIL Gravity Map of Orientale Basin

NASA Image and Video Library

2016-10-27

This color-coded map shows the strength of surface gravity around Orientale basin on Earth's moon, derived from data obtained by NASA's GRAIL mission. The GRAIL mission produced a very high-resolution map of gravity over the surface of the entire moon. This plot is zoomed in on the part of that map that features Orientale basin, where the two GRAIL spacecraft flew extremely low near the end of their mission. Their close proximity to the basin made the probes' measurements particularly sensitive to the gravitational acceleration there (due to the inverse squared law). The color scale plots the gravitational acceleration in units of "gals," where 1 gal is one centimeter per second squared, or about 1/1000th of the gravitational acceleration at Earth's surface. (The unit was devised in honor of the astronomer Galileo). Labels on the x and y axes represent latitude and longitude. http://photojournal.jpl.nasa.gov/catalog/PIA21050

Preentry communications study. Outer planets atmospheric entry probe

NASA Technical Reports Server (NTRS)

Hinrichs, C. A.

1976-01-01

A pre-entry communications study is presented for a relay link between a Jupiter entry probe and a spacecraft in hyperbolic orbit. Two generic communications links of interest are described: a pre-entry link to a spun spacecraft antenna, and a pre-entry link to a despun spacecraft antenna. The propagation environment of Jupiter is defined. Although this is one of the least well known features of Jupiter, enough information exists to reasonably establish bounds on the performance of a communications link. Within these bounds, optimal carrier frequencies are defined. The next step is to identify optimal relative geometries between the probe and the spacecraft. Optimal trajectories are established for both spun and despun spacecraft antennas. Given the optimal carrier frequencies, and the optimal trajectories, the data carrying capacities of the pre-entry links are defined. The impact of incorporating pre-entry communications into a basic post entry probe is then assessed. This assessment covers the disciplines of thermal control, power source, mass properties and design layout. A conceptual design is developed of an electronically despun antenna for use on a Pioneer class of spacecraft.

On the interpretation of Langmuir probe data inside a spacecraft sheath

NASA Astrophysics Data System (ADS)

Olson, J.; Brenning, N.; Wahlund, J.-E.; Gunell, H.

2010-10-01

If a Langmuir probe is located inside the sheath of a negatively charged spacecraft, there is a risk that the probe characteristic is modified compared to that of a free probe in the ambient plasma. We have studied this probe-in-spacecraft-sheath problem in the parameter range of a small Langmuir probe (with radius rLP<<λD) using a modified version of the orbit motion limited (OML) probe theory. We find that the ambient electron contribution Ie(ULP) to the probe characteristic is suitably analyzed in terms of three regions of applied probe potential ULP. In region I, where the probe is negatively charged (i.e., ULPU1, there is first a transition region II in applied potential, U1

A solar activity monitoring platform for SCADM

NASA Technical Reports Server (NTRS)

Kissell, K. E.; Ratcliff, D. D.

1980-01-01

The adaptation of proven space probe technology is proposed as a means of providing a solar activity monitoring platform which could be injected behind the Earth's orbital position to give 3 to 6 days advanced coverage of the solar phenomenon on the backside hemisphere before it rotates into view and affects terrestrial activities. The probe would provide some three dimensional discrimination within the ecliptic latitude. This relatively simple off-Earth probe could provide very high quality data to support the SCADM program, by transmitting both high resolution video data of the solar surface and such measurements of solar activity as particle, X-ray, ultraviolet, and radio emission fluxes. Topics covered include the orbit; constraints on the spacecraft; subsystems and their embodiments; optical imaging sensors and their operation; and the radiation-pressure attitude control system are described. The platform would be capable of mapping active regions on an hourly basis with one arc-second resolution.

KSC-05pd2409

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is shrouded in insulating blankets that were installed to serve as a heat shield. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2407

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts part of the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2408a

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2407a

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2406

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory are installing blankets that serve as heat shields around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Pioneer probe mission with orbiter option

NASA Technical Reports Server (NTRS)

1975-01-01

A spacecraft is described which is based on Pioneer 10 and 11, and existing propulsion technology; it can transport and release a probe for entry into Jupiter's atmosphere, and subsequently maneuver to place the spacecraft in orbit about Jupiter. Orbital operations last 3 years and include maneuvers to provide multiple close satellite encounters which allow the orbit to be significantly changed to explore different parts of the magnetosphere. A mission summary, a guide to related documents, and background information about Jupiter are presented along with mission analysis over the complete mission profile. Other topics discussed include the launch, interplanetary flight, probe release and orbit deflection, probe entry, orbit selection, orbit insertion, periapsis raising, spacecraft description, and the effects of Jupiter's radiation belt on both orbiter and the probe.

Reaching for the red planet

PubMed

David, L

1996-05-01

The distant shores of Mars were reached by numerous U.S. and Russian spacecraft throughout the 1960s to mid 1970s. Nearly 20 years have passed since those successful missions which orbited and landed on the Martian surface. Two Soviet probes headed for the planet in July, 1988, but later failed. In August 1993, the U.S. Mars Observer suddenly went silent just three days before it was to enter orbit around the planet and was never heard from again. In late 1996, there will be renewed activity on the launch pads with three probes departing for the red planet: 1) The U.S. Mars Global Surveyor will be launched in November on a Delta II rocket and will orbit the planet for global mapping purposes; 2) Russia's Mars '96 mission, scheduled to fly in November on a Proton launcher, consists of an orbiter, two small stations which will land on the Martian surface, and two penetrators that will plow into the terrain; and finally, 3) a U.S. Discovery-class spacecraft, the Mars Pathfinder, has a December launch date atop a Delta II booster. The mission features a lander and a microrover that will travel short distances over Martian territory. These missions usher in a new phase of Mars exploration, setting the stage for an unprecedented volley of spacecraft that will orbit around, land on, drive across, and perhaps fly at low altitudes over the planet.

Saturn Uranus atmospheric entry probe mission spacecraft system definition study

NASA Technical Reports Server (NTRS)

1973-01-01

The modifications required of the Pioneer F/G spacecraft design for it to deliver an atmospheric entry probe to the planets Saturn and Uranus are investigated. It is concluded that it is feasible to conduct such a mission within the constraints and interfaces defined. The spacecraft required to perform the mission is derived from the Pioneer F/G design, and the modifications required are generally routinely conceived and executed. The entry probe is necessarily a new design, although it draws on the technology of past, present, and imminent programs of planetary atmospheric investigations.

Spacecraft surface charging within geosynchronous orbit observed by the Van Allen Probes

DOE PAGES

Sarno-Smith, Lois K.; Larsen, Brian A.; Skoug, Ruth M.; ...

2016-02-27

Using the Helium Oxygen Proton Electron (HOPE) and Electric Field and Waves (EFW) instruments from the Van Allen Probes, we explored the relationship between electron energy fluxes in the eV and keV ranges and spacecraft surface charging. We present statistical results on spacecraft charging within geosynchronous orbit by L and MLT. An algorithm to extract the H+ charging line in the HOPE instrument data was developed to better explore intense charging events. Also, this study explored how spacecraft potential relates to electron number density, electron pressure, electron temperature, thermal electron current, and low-energy ion density between 1 and 210 eV.more » It is demonstrated that it is imperative to use both EFW potential measurements and the HOPE instrument ion charging line for examining times of extreme spacecraft charging of the Van Allen Probes. The results of this study show that elevated electron energy fluxes and high-electron pressures are present during times of spacecraft charging but these same conditions may also occur during noncharging times. Furthermore, we also show noneclipse significant negative charging events on the Van Allen Probes.« less

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

A U.S. Air Force C-5 transport aircraft arrives at Space Coast Regional Airport in Titusville, Florida, with NASA's Parker Solar Probe spacecraft aboard. The spacecraft will be offloaded and transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

A U.S. Air Force C-5 transport aircraft touches down at Space Coast Regional Airport in Titusville, Florida, with NASA's Parker Solar Probe spacecraft aboard. The spacecraft will be offloaded and transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

A U.S. Air Force C-5 transport aircraft approaches the runway for landing at Space Coast Regional Airport in Titusville, Florida, with NASA's Parker Solar Probe spacecraft aboard. The spacecraft will be offloaded and transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Jet Propulsion Laboratory: Annual Report 2002

NASA Technical Reports Server (NTRS)

2003-01-01

The year 2002 brought advances on many fronts in our space exploration ventures. A new orbiter settled in at Mars and delivered tantalizing science results suggesting a vast store of water ice under the planet's surface, a discovery that may have profound consequences for exploring Mars. A long-lived spacecraft made its final fly-bys of Jupiter's moons, while another started its final approach toward Saturn and yet another flew by an asteroid on its way to a comet. A new ocean satellite began science observations, joined in Earth orbit by a pair of spacecraft measuring our home planets gravity field, as well as JPL instruments on NASA and Japanese satellites. A major new infrared observatory and a pair of Mars rovers were readied for launch. All told, JPL is now communicating with 14 spacecraft cast like gems across the velvet expanses of the solar system. It is a far cry from the early 1960's, when JPL engineers made prodigious efforts to get the first planetary explorers off the ground and into space - an achievement of which we were especially mindful this year, as 2002 marked the 40th anniversary of the first successful planetary mission, Mariner 2, which barely reached our closest planetary neighbor, Venus. Added to this anniversary were celebrations surrounding the 25th anniversaries of the launches of Voyagers 1 and 2, two remarkable spacecraft that are still flying and are actively probing the outer realms of the solar system. These events of the past and present provide an occasion for reflection on the remarkable era of exploration that we at the Jet Propulsion Laboratory are privileged to be a part of. As 2002 neared its end, the Laboratory had yet another reason for celebration, as a new five-year management contract between NASA and the California Institute of Technology was signed that calls for a closer working relationship with NASA and other NASA centers as a member of the 'One NASA' team. There is a strong emphasis on cost control and management, areas in which we can improve, enabling us to become more competitive. This new agreement again confirms NASA's trust and faith in Caltech and JPL, in which we should all take great pride. If the history of JPL were a book, we are on the verge of turning the page to one that promises to be one of the most exciting and busiest chapters in JPL's history. In 2003 and 2004, we will launch 11 spacecraft or major payloads. We will land two rovers on Mars; put a spacecraft in orbit around Saturn, deliver a probe to the surface of its largest moon, Titan, and map Titan's surface withimaging radar; send a spacecraft past a comet collecting samples from its tail, while another one is launched toward a comet impact; bring a capsule back to Earth with the first samples ever collected beyond the orbit of the Moon; map the skies in the ultraviolet as well as the infrared spectrum to unprecedented accuracy; and continue the mapping of ocean topography and winds on our home planet, Earth.

Comparison of interball-2 spacecraft potential from IESP and KM-7 experiments in high-latitude regions of the magnetosphere at altitudes of 2-3 RE

NASA Astrophysics Data System (ADS)

Smirnova, N.; Afonin, V.; Smilauer, Ja.; Stanev, G.

Measurements of Interball-2 spacecraft potential by two instruments, IESP and KM-7, are reviewed and simultaneous measurements are compared. Unacceptable discrepancy between results of spacecraft potential measurements, including opposite signs, was found. Actually, both experiments are methodically identical: they used the same type of sensor - spherical Langmuir probes operating in the ``floating'' mode, and they have measured the same parameter - the voltage difference between the probe and the satellite structure. The IESP instrument measured one value of this parameter at fixed bias current to the probe. The KM-7 measured the whole current-voltage characteristic (the probe current as a function of the probe potential), which consists of 11 IESP-type measurements at different values of bias current. The difference lies only in the way of technical implementation, as the probes were operating in different ambient conditions. The IESP probes were mounted at the ends of long booms and thus were affected by the solar UV emission, while the KM-7 probe was rather well protected against UV emission by proper mounting and screening the head of the sensor from both direct UV emission and those reflected from spacecraft elements. The comparison of two data sets and variations along the orbit has shown, that KM-7 correctly measures the spacecraft potential. In high-latitude inner magnetosphere (in auroral region and polar cap) at altitudes 2-3 RE the spacecraft potential was predominantly negative down to -10 V, increasing up to about +5 V in some locations at rather extended parts of the satellite orbit. Reasonably good agreement between two experiments was obtained only at spacecraft potential <= -2 V and after inversion the sign of available calibration curve of IESP experiment; in this case both experiments very accurately reflect variation of potential data even in the small details. The operation mode of IESP experiment was not optimal and requires further analysis. The wave results obtained with IESP may be considered as reliable only when both experiments show, after inversion of available IESP calibration curve, coincident data, but the phase relations, if any, will be inversed in any case. The method of spacecraft potential measurements adopted in IESP should be used only for positive potential; if realspacecraft potential is negative, the method gives wrong and misleading results.

KSC-05pd2408

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts part of the blanket that it is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

Preparations are underway to offload NASA's Parker Solar Probe spacecraft, secured in its shipping container, from a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The spacecraft will be transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a balloon gently lifts the solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a balloon gently lifts the solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with all four solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with all four solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - A worker in the NASA spacecraft processing facility on North Vandenberg Air Force Base adjust the supports on a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - A worker in the NASA spacecraft processing facility on North Vandenberg Air Force Base adjust the supports on a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with two solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with two solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, Dr. Francis Everitt, principal investigator, and Brad Parkinson, co-principal investigator, both from Stanford University, hold one of the small gyroscopes used in the Gravity Probe B spacecraft. The GP-B towers behind them. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-10

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, Dr. Francis Everitt, principal investigator, and Brad Parkinson, co-principal investigator, both from Stanford University, hold one of the small gyroscopes used in the Gravity Probe B spacecraft. The GP-B towers behind them. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a worker checks the installation of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a worker checks the installation of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare for the installation of solar array panel 3 on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare for the installation of solar array panel 3 on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare to rotate the framework containing one of four solar panels to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare to rotate the framework containing one of four solar panels to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base work on a solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base work on a solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to attach the top of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to attach the top of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach a solar array panel on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach a solar array panel on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach supports to a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-03

VANDENBERG AFB, CALIF. - Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach supports to a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

Systems design study of the Pioneer Venus spacecraft. Volume 1. Technical analyses and tradeoffs, sections 5-6 (part 2 of 4)

NASA Technical Reports Server (NTRS)

1973-01-01

System configuration concepts, and tradeoffs are presented for the Atlas/Centaur, and the Thor/Delta probes. Spacecraft system definition, and the probe system definition are discussed along with the mission reliability.

Radiometric Spacecraft Tracking for Deep Space Navigation

NASA Technical Reports Server (NTRS)

Lanyi, Gabor E.; Border, James S.; Shin, Dong K.

2008-01-01

Interplanetary spacecraft navigation relies on three types of terrestrial tracking observables.1) Ranging measures the distance between the observing site and the probe. 2) The line-of-sight velocity of the probe is inferred from Doppler-shift by measuring the frequency shift of the received signal with respect to the unshifted frequency. 3) Differential angular coordinates of the probe with respect to natural radio sources are nominally obtained via a differential delay technique of (Delta) DOR (Delta Differential One-way Ranging). The accuracy of spacecraft coordinate determination depends on the measurement uncertainties associated with each of these three techniques. We evaluate the corresponding sources of error and present a detailed error budget.

KSC-05pd2416

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the media (also dressed in clean room suits) learn about NASA’s New Horizons spacecraft (at left) from New Horizons Mission Systems Engineer David Kusnierkiewicz, in the center. Behind Kusnierkiewicz is one half of the fairing that will enclose the spacecraft for launch, scheduled for January 2006. The media event brought photographers and reporters to the site to talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Electric Propulsion Options for a Magnetospheric Mapping Mission

NASA Technical Reports Server (NTRS)

Oleson, Steven; Russell, Chris; Hack, Kurt; Riehl, John

1998-01-01

The Twin Electric Magnetospheric Probes Exploring on Spiral Trajectories mission concept was proposed as a Middle Explorer class mission. A pre-phase-A design was developed which utilizes the advantages of electric propulsion for Earth scientific spacecraft use. This paper presents propulsion system analyses performed for the proposal. The proposed mission required two spacecraft to explore near circular orbits 0.1 to 15 Earth radii in both high and low inclination orbits. Since the use of chemical propulsion would require launch vehicles outside the Middle Explorer class a reduction in launch mass was sought using ion, Hall, and arcjet electric propulsion system. Xenon ion technology proved to be the best propulsion option for the mission requirements requiring only two Pegasus XL launchers. The Hall thruster provided an alternative solution but required two larger, Taurus launch vehicles. Arcjet thrusters did not allow for significant launch vehicle reduction in the Middle Explorer class.

System design of the Pioneer Venus spacecraft. Volume 4: Probe bus and orbiter spacecraft vehicle studies

NASA Technical Reports Server (NTRS)

Bozajian, J. M.

1973-01-01

The requirements, trades, and design descriptions for the probe bus and orbiter spacecraft configurations, structure, thermal control, and harness are defined. Designs are developed for Thor/Delta and Atlas/Centaur launch vehicles with the latter selected as the final baseline. The major issues examined in achieving the baseline design are tabulated. The importance of spin axis orientation because of the effect on science experiments and earth communications is stressed.

System design of the Pioneer Venus spacecraft. Volume 2: Science

NASA Technical Reports Server (NTRS)

Acheson, L. K.

1973-01-01

The objectives of the low-cost Pioneer Venus space probe program are discussed. The space mission and science requirements are analyzed. The subjects considered are as follows: (1) the multiprobe mission, (2) the orbiter mission, (3) science payload accomodations, and (4) orbiter spacecraft experimental interface specifications. Tables of data are provided to show the science allocations for large and small probes. Illustrations of the systems and components of various probe configurations are included.

MAP Propulsion System Thermal Design

NASA Technical Reports Server (NTRS)

Mosier, Carol L.

2003-01-01

The propulsion system of the Microwave Anisotropy Probe (MAP) had stringent requirements that made the thermal design unique. To meet instrument stability requirements the system had to be designed to keep temperatures of all components within acceptable limits without heater cycling. Although the spacecraft remains at a fixed 22 sun angle at L2, the variations in solar constant, property degradation, and bus voltage range all significantly affect the temperature. Large portions of the fuel lines are external to the structure and all components are mounted to non-conductive composite structure. These two facts made the sensitivity to the MLI effective emissivity and bus temperature very high. Approximately two years prior to launch the propulsion system was redesigned to meet MAP requirements. The new design utilized hardware that was already installed in order to meet schedule constraints. The spacecraft design and the thermal requirements were changed to compensate for inadequacies of the existing hardware. The propulsion system consists of fuel lines, fill and drain lines/valve, eight thrusters, a HXCM, and a propulsion tank. A voltage regulator was added to keep critical components within limits. Software was developed to control the operational heaters. Trim resistors were put in series with each operational heater circuits and the tank survival heater. A highly sophisticated test program, which included real time model correlation, was developed to determine trim resistors sizes. These trim resistors were installed during a chamber break and verified during thermal balance testing.

Performance Evaluation Gravity Probe B Design

NASA Technical Reports Server (NTRS)

Francis, Ronnie; Wells, Eugene M.

1996-01-01

This final report documents the work done to develop a 6 degree-of-freedom simulation of the Lockheed Martin Gravity Probe B (GPB) Spacecraft. This simulation includes the effects of vehicle flexibility and propellant slosh. The simulation was used to investigate the control performance of the spacecraft when subjected to realistic on orbit disturbances.

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers stand by as the balloon at right is released to lift the solar array panel into position for installation on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

NASA Image and Video Library

2003-11-04

VANDENBERG AFB, CALIF. - In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers stand by as the balloon at right is released to lift the solar array panel into position for installation on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASA’s Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einstein’s general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

Samara Probe For Remote Imaging

NASA Technical Reports Server (NTRS)

Burke, James D.

1989-01-01

Imaging probe descends through atmosphere of planet, obtaining images of ground surface as it travels. Released from aircraft over Earth or from spacecraft over another planet. Body and single wing shaped like samara - winged seed like those of maple trees. Rotates as descends, providing panoramic view of terrain below. Radio image obtained by video camera to aircraft or spacecraft overhead.

The Sheath-less Planar Langmuir Probe

NASA Astrophysics Data System (ADS)

Cooke, D. L.

2017-12-01

The Langmuir probe is one of the oldest plasma diagnostics, provided the plasma density and species temperature from analysis of a current-voltage curve as the voltage is swept over a practically chosen range. The analysis depends on a knowledge or theory of the many factors that influence the current-voltage curve including, probe shape, size, nearby perturbations, and the voltage reference. For applications in Low Earth Orbit, the Planar Langmuir Probe, PLP, is an attractive geometry because the ram ion current is very constant over many Volts of a sweep, allowing the ion density and electron temperature to be determined independently with the same instrument, at different points on the sweep. However, when the physical voltage reference is itself small and electrically floating as with a small spacecraft, the spacecraft and probe system become a double probe where the current collection theory depends on the interaction of the spacecraft with the plasma which is generally not as simple as the probe itself. The Sheath-less PLP, SPLP, interlaces on a single ram facing surface, two variably biased probe elements, broken into many small and intertwined segments on a scale smaller than the plasma Debye length. The SPLP is electrically isolated from the rest of the spacecraft. For relative bias potentials of a few volts, the ion current to all segments of each element will be constant, while the electron currents will vary as a function of the element potential and the electron temperature. Because the segments are small, intertwined, and floating, the assembly will always present the same floating potential to the plasma, with minimal growth as a function of voltage, thus sheath-less and still planar. This concept has been modelled with Nascap, and tested with a physical model inserted into a Low Earth Orbit-like chamber plasma. Results will be presented.

The Recovery of TOMS-EP

NASA Technical Reports Server (NTRS)

Robertson, Brent; Sabelhaus, Phil; Mendenhall, Todd; Fesq, Lorraine

1998-01-01

On December 13th 1998, the Total Ozone Mapping Spectrometer - Earth Probe (TOMS-EP) spacecraft experienced a Single Event Upset which caused the system to reconfigure and enter a Safe Mode. This incident occurred two and a half years after the launch of the spacecraft which was designed for a two year life. A combination of factors, including changes in component behavior due to age and extended use, very unfortunate initial conditions and the safe mode processing logic prevented the spacecraft from entering its nominal long term storage mode. The spacecraft remained in a high fuel consumption mode designed for temporary use. By the time the onboard fuel was exhausted, the spacecraft was Sun pointing in a high rate flat spin. Although the uncontrolled spacecraft was initially in a power and thermal safe orientation, it would not stay in this state indefinitely due to a slow precession of its momentum vector. A recovery team was immediately assembled to determine if there was time to develop a method of despinning the vehicle and return it to normal science data collection. A three stage plan was developed that used the onboard magnetic torque rods as actuators. The first stage was designed to reduce the high spin rate to within the linear range of the gyros. The second stage transitioned the spacecraft from sun pointing to orbit reference pointing. The final stage returned the spacecraft to normal science operation. The entire recovery scenario was simulated with a wide range of initial conditions to establish the expected behavior. The recovery sequence was started on December 28th 1998 and completed by December 31st. TOMS-EP was successfully returned to science operations by the beginning of 1999. This paper describes the TOMS-EP Safe Mode design and the factors which led to the spacecraft anomaly and loss of fuel. The recovery and simulation efforts are described. Flight data are presented which show the performance of the spacecraft during its return to science. Finally, lessons learned are presented.

Choosing an efficient option of the combined propulsion system and flight profile of the INTERHELIO-PROBE spacecraft

NASA Astrophysics Data System (ADS)

Platov, I. V.; Simonov, A. V.; Konstantinov, M. S.

2016-12-01

The paper is devoted to the design features of the prospective Russian INTERHELIO-PROBE spacecraft using, depending on the configuration version, an electric or chemical propulsion system as a sustainer. The scientific goal of the mission is the study of near-solar space from close distances (60-70 solar radii). The paper presents the description of several versions of the spacecraft options depending on the installed propulsion system, as well as the main characteristics of the flight profile depending on the engine type.

Electromagnetic plasma particle simulations on Solar Probe Plus spacecraft interaction with near-Sun plasma environment

NASA Astrophysics Data System (ADS)

Miyake, Yohei; Usui, Hideyuki

It is necessary to predict the nature of spacecraft-plasma interactions in extreme plasma conditions such as in the near-Sun environment. The spacecraft environment immersed in the solar corona is characterized by the small Debye length due to dense (7000 mathrm{/cc}) plasmas and a large photo-/secondary electron emission current emitted from the spacecraft surfaces, which lead to distinctive nature of spacecraft-plasma interactions [1,2,3]. In the present study, electromagnetic field perturbation around the Solar Probe Plus (SPP) spacecraft is examined by using our original EM-PIC (electromagnetic particle-in-cell) plasma simulation code called EMSES. In the simulations, we consider the SPP spacecraft at perihelion (0.04 mathrm{AU} from the Sun) and important physical effects such as spacecraft charging, photoelectron and secondary electron emission, solar wind plasma flow including the effect of spacecraft orbital velocity, and the presence of a background magnetic field. Our preliminary results show that both photoelectrons and secondary electrons from the spacecraft are magnetized in a spatial scale of several meters, and make drift motion due the presence of the background convection electric field. This effect leads to non-axisymmetric distributions of the electron density and the resultant electric potential near the spacecraft. Our simulations predict that a strong (˜ 100 mathrm{mV/m}) spurious electric field can be observed by the probe measurement on the spacecraft due to such a non-axisymmetric effect. We also confirm that the large photo-/secondary electron current alters magnetic field intensity around the spacecraft, but the field variation is much smaller than the background magnetic field magnitude (a few mathrm{nT} compared to a few mathrm{mu T}). [1] Ergun et al., textit{Phys. Plasmas}, textbf{17}, 072903, 2010. [2] Guillemant et al., textit{Ann. Geophys.}, textbf{30}, 1075-1092, 2012. [3] Guillemant et al., textit{IEEE Trans. Plasma Sci.}, textbf{41}, 3338-3348, 2013.

The Cassini-Huygens Mission Overview

NASA Technical Reports Server (NTRS)

Vandermey, Nancy; Paczkowski, Brian G.

2006-01-01

The Cassini-Huygens Program is an international science mission to the Saturnian system. Three space agencies and seventeen nations contributed to building the Cassini spacecraft and Huygens probe. The Cassini orbiter is managed and operated by NASA's Jet Propulsion Laboratory. The Huygens probe was built and operated by the European Space Agency. The mission design for Cassini-Huygens calls for a four-year orbital survey of Saturn, its rings, magnetosphere, and satellites, and the descent into Titan's atmosphere of the Huygens probe. The Cassini orbiter tour consists of 76 orbits around Saturn with 45 close Titan flybys and 8 targeted icy satellite flybys. The Cassini orbiter spacecraft carries twelve scientific instruments that are performing a wide range of observations on a multitude of designated targets. The Huygens probe carried six additional instruments that provided in-situ sampling of the atmosphere and surface of Titan. The multi-national nature of this mission poses significant challenges in the area of flight operations. This paper will provide an overview of the mission, spacecraft, organization and flight operations environment used for the Cassini-Huygens Mission. It will address the operational complexities of the spacecraft and the science instruments and the approach used by Cassini-Huygens to address these issues.

A simple method for verifying the deployment of the TOMS-EP solar arrays

NASA Technical Reports Server (NTRS)

Koppersmith, James R.; Ketchum, Eleanor

1995-01-01

The Total Ozone Mapping Spectrometer-Earth Probe (TOMS-EP) mission relies upon a successful deployment of the spacecraft's solar arrays. Several methods of verification are being employed to ascertain the solar array deployment status, with each requiring differing amounts of data. This paper describes a robust attitude-independent verification method that utilizes telemetry from the coarse Sun sensors (CSS's) and the three-axis magnetometers (TAM's) to determine the solar array deployment status - and it can do so with only a few, not necessarily contiguous, points of data. The method developed assumes that the solar arrays are deployed. Telemetry data from the CSS and TAM are converted to the Sun and magnetic field vectors in spacecraft body coordinates, and the angle between them is calculated. Deployment is indicated if this angle is within a certain error tolerance of the angle between the reference Sun and magnetic field vectors. Although several other methods can indicate a non-deployed state, with this method there is a 70% confidence level in confirming deployment as well as a nearly 100% certainty in confirming a non-deployed state. In addition, the spacecraft attitude (which is not known during the first orbit after launch) is not needed for this algorithm because the angle between the Sun and magnetic field vectors is independent of the spacecraft attitude. This technique can be applied to any spacecraft with a TAM and with CSS's mounted on the solar array(s).

Gravity Probe B spacecraft description

NASA Astrophysics Data System (ADS)

Bennett, Norman R.; Burns, Kevin; Katz, Russell; Kirschenbaum, Jon; Mason, Gary; Shehata, Shawky

2015-11-01

The Gravity Probe B spacecraft, developed, integrated, and tested by Lockheed Missiles & Space Company and later Lockheed Martin Corporation, consisted of structures, mechanisms, command and data handling, attitude and translation control, electrical power, thermal control, flight software, and communications. When integrated with the payload elements, the integrated system became the space vehicle. Key requirements shaping the design of the spacecraft were: (1) the tight mission timeline (17 months, 9 days of on-orbit operation), (2) precise attitude and translational control, (3) thermal protection of science hardware, (4) minimizing aerodynamic, magnetic, and eddy current effects, and (5) the need to provide a robust, low risk spacecraft. The spacecraft met all mission requirements, as demonstrated by dewar lifetime meeting specification, positive power and thermal margins, precision attitude control and drag-free performance, reliable communications, and the collection of more than 97% of the available science data.

Probe design

NASA Technical Reports Server (NTRS)

Cowan, W.

1974-01-01

Outer planetary probe designs consider mission characteristics, structural configuration, delivery mode, scientific payload, environmental extremes, mass properties, and the launch vehicle and spacecraft interface.

The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 1; The Study for the Distance 4.5Rs

NASA Technical Reports Server (NTRS)

Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

2010-01-01

Our report devotes a 3D numerical hybrid model of the interaction of the solar wind with the Solar Probe spacecraft. The Solar Probe Plus (SPP) model includes 3 main parts, namely, a non-conducting heat shield, a support system, and cylindrical section or spacecraft bus that contains the particle analysis devices and antenna. One observes an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of about (0.06-0.6) V/m. The compression waves and the jumps in an electric field with an amplitude of about (0.15-0.7) V/m were also observed. The wave amplitudes are comparable to or greater than previously estimated max wave amplitudes that SPP is expected to measure. The results of our hybrid simulation will be useful for understanding the plasma environment near the SPP spacecraft at the distance 4.5 Rs. Future simulation will take into account the charging of the spacecraft, the charge separation effects, an outgassing from heat shield, a photoionization and an electron impact ionization effects near the spacecraft.

Science Planning for the Solar Probe Plus NASA Mission

NASA Astrophysics Data System (ADS)

Kusterer, M. B.; Fox, N. J.; Turner, F. S.; Vandegriff, J. D.

2015-12-01

With a planned launch in 2018, there are a number of challenges for the Science Planning Team (SPT) of the Solar Probe Plus mission. The geometry of the celestial bodies and the spacecraft during some of the Solar Probe Plus mission orbits cause limited uplink and downlink opportunities. The payload teams must manage the volume of data that they write to the spacecraft solid-state recorders (SSR) for their individual instruments for downlink to the ground. The aim is to write the instrument data to the spacecraft SSR for downlink before a set of data downlink opportunities large enough to get the data to the ground and before the start of another data collection cycle. The SPT also intend to coordinate observations with other spacecraft and ground based systems. To add further complexity, two of the spacecraft payloads have the capability to write a large volumes of data to their internal payload SSR while sending a smaller "survey" portion of the data to the spacecraft SSR for downlink. The instrument scientists would then view the survey data on the ground, determine the most interesting data from their payload SSR, send commands to transfer that data from their payload SSR to the spacecraft SSR for downlink. The timing required for downlink and analysis of the survey data, identifying uplink opportunities for commanding data transfers, and downlink opportunities big enough for the selected data within the data collection period is critical. To solve these challenges, the Solar Probe Plus Science Working Group has designed a orbit-type optimized data file priority downlink scheme to downlink high priority survey data quickly. This file priority scheme would maximize the reaction time that the payload teams have to perform the survey and selected data method on orbits where the downlink and uplink availability will support using this method. An interactive display and analysis science planning tool is being designed for the SPT to use as an aid to planning. The tool will integrate the data file priority downlink scheme, payload data volume allocations, spacecraft ephemeris, attitude, downlink and uplink schedules, spacecraft and payload activities, and other spacecraft ephemeris. A prototype of the tool is in development using notional inputs obtained from the spacecraft engineering teams.

Preliminary design of the thermal protection system for solar probe

NASA Technical Reports Server (NTRS)

Dirling, R. B., Jr.; Loomis, W. C.; Heightland, C. N.

1982-01-01

A preliminary design of the thermal protection system for the NASA Solar Probe spacecraft is presented. As presently conceived, the spacecraft will be launched by the Space Shuttle on a Jovian swing-by trajectory and at perihelion approach to three solar radii of the surface of the Earth's sun. The system design satisfies maximum envelope, structural integrity, equipotential, and mass loss/contamination requirements by employing lightweight carbon-carbon emissive shields. The primary shield is a thin shell, 15.5-deg half-angle cone which absorbs direct solar flux at up to 10-deg off-nadir spacecraft pointing angles. Secondary shields of sandwich construction and low thickness-direction thermal conductivity are used to reduce the primary shield infrared radiation to the spacecraft payload.

Gravity Probe-B Spacecraft attitude control based on the dynamics of slosh wave-induced fluid stress distribution on rotating dewar container of cryogenic propellant

NASA Technical Reports Server (NTRS)

Hung, R. J.; Lee, C. C.; Leslie, F. W.

1991-01-01

The dynamical behavior of fluids, in particular the effect of surface tension on partially-filled rotating fluids, in a full-scale Gravity Probe-B Spacecraft propellant dewar tank imposed by various frequencies of gravity jitters have been investigated. Results show that fluid stress distribution exerted on the outer and inner walls of rotating dewar are closely related to the characteristics of slosh waves excited on the liquid-vapor interface in the rotating dewar tank. This can provide a set of tool for the spacecraft dynamic control leading toward the control of spacecraft unbalance caused by the uneven fluid stress distribution due to slosh wave excitations.

System Design under Uncertainty: Evolutionary Optimization of the Gravity Probe-B Spacecraft

NASA Technical Reports Server (NTRS)

Pullen, Samuel P.; Parkinson, Bradford W.

1994-01-01

This paper discusses the application of evolutionary random-search algorithms (Simulated Annealing and Genetic Algorithms) to the problem of spacecraft design under performance uncertainty. Traditionally, spacecraft performance uncertainty has been measured by reliability. Published algorithms for reliability optimization are seldom used in practice because they oversimplify reality. The algorithm developed here uses random-search optimization to allow us to model the problem more realistically. Monte Carlo simulations are used to evaluate the objective function for each trial design solution. These methods have been applied to the Gravity Probe-B (GP-B) spacecraft being developed at Stanford University for launch in 1999, Results of the algorithm developed here for GP-13 are shown, and their implications for design optimization by evolutionary algorithms are discussed.

Artist concept of Galileo spacecraft

NASA Technical Reports Server (NTRS)

1988-01-01

Galileo spacecraft is illustrated in artist concept. Gallileo, named for the Italian astronomer, physicist and mathematician who is credited with construction of the first complete, practical telescope in 1620, will make detailed studies of Jupiter. A cooperative program with the Federal Republic of Germany the Galileo mission will amplify information acquired by two Voyager spacecraft in their brief flybys. Galileo is a two-element system that includes a Jupiter-orbiting observatory and an entry probe. Jet Propulsion Laboratory (JPL) is Galileo project manager and builder of the main spacecraft. Ames Research Center (ARC) has responsibility for the entry probe, which was built by Hughes Aircraft Company and General Electric. Galileo will be deployed from the payload bay (PLB) of Atlantis, Orbiter Vehicle (OV) 104, during mission STS-34.

PC-403: Pioneer Venus multiprobe spacecraft mission operational characteristics document, volume 3

NASA Technical Reports Server (NTRS)

Barker, F. C.

1978-01-01

The Pioneer Venus spacecraft primary and backup operational modes and operational limitations for maneuvers, roll references transfer, attitude determination, spacecraft power discipline and spacecraft thermal discipline, are described. The functions and operations of the large and small probes, as well detailed performance in the normal operating modes and backup modes are presented.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

NASA's Parker Solar Probe, secured in its shipping container, arrives at the Astrotech processing facility near the agency's Kennedy Space Center in Florida. The spacecraft arrived aboard a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

NASA's Parker Solar Probe, secured in its shipping container, is offloaded from a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The spacecraft will be transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

NASA's Parker Solar Probe, secured in its shipping container, has been offloaded from a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The spacecraft will be transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

NASA's Parker Solar Probe, secured in its shipping container, arrives aboard a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The spacecraft will be offloaded and transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

Gravity Probe B

NASA Image and Video Library

2003-07-11

Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment. Mechanical and electrical ground support equipment will be set up and necessary connections made with the spacecraft. Spacecraft battery conditioning will also begin. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einstein’s general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Once in orbit, for 18 months each gyroscope’s spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASA’s Marshall Space Flight Center.

KSC-03PD-3277

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a worker checks the installation of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3280

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with two solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3270

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach a solar array panel on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3281

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, the Gravity Probe B spacecraft is seen with all four solar array panels installed. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3267

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base work on a solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3271

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach a solar array panel on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3266

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare for the installation of solar array panel 3 on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

Observation and Numerical Simulation of Cavity Mode Oscillations Excited by an Interplanetary Shock

NASA Astrophysics Data System (ADS)

Takahashi, Kazue; Lysak, Robert; Vellante, Massimo; Kletzing, Craig A.; Hartinger, Michael D.; Smith, Charles W.

2018-03-01

Cavity mode oscillations (CMOs) are basic magnetohydrodynamic eigenmodes in the magnetosphere predicted by theory and are expected to occur following the arrival of an interplanetary shock. However, observational studies of shock-induced CMOs have been sparse. We present a case study of a dayside ultralow-frequency wave event that exhibited CMO properties. The event occurred immediately following the arrival of an interplanetary shock at 0829 UT on 15 August 2015. The shock was observed in the solar wind by the Time History of Events and Macroscale Interactions during Substorms-B and -C spacecraft, and magnetospheric ultralow-frequency waves were observed by multiple spacecraft including the Van Allen Probe-A and Van Allen Probe-B spacecraft, which were located in the dayside plasmasphere at L ˜1.4 and L ˜ 2.4, respectively. Both Van Allen Probes spacecraft detected compressional poloidal mode oscillations at ˜13 mHz (fundamental) and ˜26 mHz (second harmonic). At both frequencies, the azimuthal component of the electric field (Eϕ) lagged behind the compressional component of the magnetic field (Bμ) by ˜90°. The frequencies and the Eϕ-Bμ relative phase are in good agreement with the CMOs generated in a dipole magnetohydrodynamic simulation that incorporates a realistic plasma mass density distribution and ionospheric boundary condition. The oscillations were also detected on the ground by the European quasi-Meridional Magnetometer Array, which was located near the magnetic field footprints of the Van Allen Probes spacecraft.

An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter

NASA Astrophysics Data System (ADS)

Wurz, P.; Lasi, D.; Thomas, N.; Piazza, D.; Galli, A.; Jutzi, M.; Barabash, S.; Wieser, M.; Magnes, W.; Lammer, H.; Auster, U.; Gurvits, L. I.; Hajdas, W.

2017-08-01

We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (<100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes ( 1 km), during the probe's fast ( km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. All in all, it is demonstrated how the descent probe has the potential to provide a high science return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe for the former Europa-Jupiter System Mission of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission.

Design, Fabrication, and Testing of Emissive Probes to Determine the Plasma Potential of the Plumes of Various Electric Thrusters

NASA Technical Reports Server (NTRS)

Chen, Erinna M.

2005-01-01

A significant problem in the use of electric thrusters in spacecraft is the formation of low-energy ions in the thruster plume. Low-energy ions are formed in the plume via random collisions between high-velocity ions ejected from the thruster and slow-moving neutral atoms of propellant effusing from the engine. The sputtering of spacecraft materials due to interactions with low-energy ions may result in erosion or contamination of the spacecraft. The trajectory of these ions is determined primarily by the plasma potential of the plume. Thus, accurate characterization of the plasma potential is essential to predicting low-energy ion contamination. Emissive probes were utilized to determine the plasma potential. When the ion and electron currents to the probe are balanced, the potential of such probes float to the plasma potential. Two emissive probes were fabricated; one utilizing a DC power supply, another utilizing a rectified AC power source. Labview programs were written to coordinate and automate probe motion in the thruster plume. Employing handshaking interaction, these motion programs were synchronized to various data acquisition programs to ensure precision and accuracy of the measurements. Comparing these experimental values to values from theoretical models will allow for a more accurate prediction of low-energy ion interaction.

MIMES and GeoShack

NASA Technical Reports Server (NTRS)

1990-01-01

It is the goal of mankind to eventually visit Mars. It would be valuable to gain scientific information about the planet. The Multiple Integrated Microspacecraft Exploration System (MIMES) is designed for that very purpose. The MIMES mission will send to Mars a spacecraft carrying five probes, each of which will decend to the Martian surface to engage in scientific experiments. There will be two types of probes, a penetrator that will embed itself in the Martian surface, and a soft lander. The probes will transmit scientific data to the carrier spacecraft, which will relay the information to Earth. Information is given on mission instrumentation and operations.

PIONEER VENUS 2 MULTI PROBE IS ENCAPSULATED IN PROTECTIVE SHROUD

NASA Technical Reports Server (NTRS)

1978-01-01

Encapsulation of the Pioneer Venus Multiprobe in its protective nose fairing is closely monitored by technicians in Hangar AO. The 2,000-pound spacecraft is one of two being launched toward the planet Venus. The Multiprobe is scheduled for launch aboard an Atlas Centaur rocket on August 7. Flying a direct path to the cloud-shrouded planet, the Multiprobe will reach Venus five days after the arrival of its sister spacecraft, the Pioneer Venus Orbiter, which was launched May 20, 1978. Three weeks before the Multiprobe reaches Venus, its four heavily instrumented scientific probes (seen on top of the spacecraft's main body or ''bus'') will be released and will impact at various points on the planet's surface. Together, the two spacecraft will conduct a thorough scientific exploration of the planet Venus.

Refined gravity determination at small bodies through landing probes

NASA Astrophysics Data System (ADS)

Bellerose, J.

2012-02-01

Very small objects of the near-Earth population have not been visited to date, and may be among the next targets for human exploration. As density is a strong indication of the body origin and intrinsic properties, determining the mass is one of the most important goals. The past missions to Eros and Itokawa resulted in mass and density estimates to less than five percent error, allowing precise mission planning while giving new insights on the body structure. Current mass determination techniques have limitations in the low gravity regime, and spacecraft tracking at very small asteroids is challenging. We investigate the constraints on measuring the mass at very small near-Earth objects, and their consequences on proximity operation planning. An alternative option to spacecraft radio tracking is to use surface probes. The near-surface and landing dynamics can be observed and tracked by the host spacecraft, providing higher resolution measurements of the NEA gravity pull. We show analytical methods to estimate the performance of given proximity operations, and simulations of spacecraft and probe dynamics at NEAs less than 100 m in diameter.

Ring Current He Ion Control by Bounce Resonant ULF Waves

NASA Astrophysics Data System (ADS)

Kim, Hyomin; Gerrard, Andrew J.; Lanzerotti, Louis J.; Soto-Chavez, Rualdo; Cohen, Ross J.; Manweiler, Jerry W.

2017-12-01

Ring current energy He ion (˜65 keV to ˜520 keV) differential flux data from the Radiation Belt Storm Probe Ion Composition Experiment (RBSPICE) instrument aboard the Van Allan Probes spacecraft show considerable variability during quiet solar wind and geomagnetic time periods. Such variability is apparent from orbit to orbit (˜9 h) of the spacecraft and is observed to be ˜50-100% of the nominal flux. Using data from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instrument, also aboard the Van Allen Probes spacecraft, we identify that a dominant source of this variability is from ULF waveforms with periods of tens of seconds. These periods correspond to the bounce resonant timescales of the ring current He ions being measured by RBSPICE. A statistical survey using the particle and field data for one full spacecraft precession period (approximately 2 years) shows that the wave and He ion flux variations are generally anticorrelated, suggesting the bounce resonant pitch angle scattering process as a major component in the scattering of He ions.

Remote sensing of reconnection via ARTEMIS dual-spacecraft observations

NASA Astrophysics Data System (ADS)

Kiehas, Stefan; Angelopoulos, Vassilis; Runov, Andrei; Li, Shan-Shan

2013-04-01

Each month the two ARTEMIS probes spend about four days in the Earth's magnetotail near lunar orbit. Due to the near-equatorial orbit, the probes spend a considerable time near and inside the plasma sheet. This allows us to investigate large-scale effects of reconnection, such as flux ropes and high-speed flows, utilizing dual-probe observations on a regular basis. On August 31, 2012 around 03:00 UT, the ARTEMIS probes were separated by only 350 km in X_GSW and 0.6 (1) RE in Y_GSW (Z_GSW), where GSW denotes the Geocentric Solar Wind coordinate system, which x-axis is antiparallel to the solar wind flow direction. The two probes observe several TCRs and flux ropes. The inter-spacecraft separation allows us to determine the size of these structures to be not more than 6 RE in z. Counterstreaming beams observed by both probes indicate the simultaneous activity of two X-lines, earthward and tailward of the probes, respectively.

Multipoint Observations of Energetic Particle Injections and Substorm Activity During a Conjunction Between Magnetospheric Multiscale (MMS) and Van Allen Probes

NASA Astrophysics Data System (ADS)

Turner, D. L.; Fennell, J. F.; Blake, J. B.; Claudepierre, S. G.; Clemmons, J. H.; Jaynes, A. N.; Leonard, T.; Baker, D. N.; Cohen, I. J.; Gkioulidou, M.; Ukhorskiy, A. Y.; Mauk, B. H.; Gabrielse, C.; Angelopoulos, V.; Strangeway, R. J.; Kletzing, C. A.; Le Contel, O.; Spence, H. E.; Torbert, R. B.; Burch, J. L.; Reeves, G. D.

2017-11-01

This study examines multipoint observations during a conjunction between Magnetospheric Multiscale (MMS) and Van Allen Probes on 7 April 2016 in which a series of energetic particle injections occurred. With complementary data from Time History of Events and Macroscale Interactions during Substorms, Geotail, and Los Alamos National Laboratory spacecraft in geosynchronous orbit (16 spacecraft in total), we develop new insights on the nature of energetic particle injections associated with substorm activity. Despite this case involving only weak substorm activity (maximum AE <300 nT) during quiet geomagnetic conditions in steady, below-average solar wind, a complex series of at least six different electron injections was observed throughout the system. Intriguingly, only one corresponding ion injection was clearly observed. All ion and electron injections were observed at <600 keV only. MMS reveals detailed substructure within the largest electron injection. A relationship between injected electrons with energy <60 keV and enhanced whistler mode chorus wave activity is also established from Van Allen Probes and MMS. Drift mapping using a simplified magnetic field model provides estimates of the dispersionless injection boundary locations as a function of universal time, magnetic local time, and L shell. The analysis reveals that at least five electron injections, which were localized in magnetic local time, preceded a larger injection of both electrons and ions across nearly the entire nightside of the magnetosphere near geosynchronous orbit. The larger ion and electron injection did not penetrate to L < 6.6, but several of the smaller electron injections penetrated to L < 6.6. Due to the discrepancy between the number, penetration depth, and complexity of electron versus ion injections, this event presents challenges to the current conceptual models of energetic particle injections.

Multipoint Observations of Energetic Particle Injections and Substorm Activity During a Conjunction Between Magnetospheric Multiscale (MMS) and Van Allen Probes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, Drew L.; Fennell, J. F.; Blake, J. B.

Here, this study examines multipoint observations during a conjunction between Magnetospheric Multiscale (MMS) and Van Allen Probes on 7 April 2016 in which a series of energetic particle injections occurred. With complementary data from Time History of Events and Macroscale Interactions during Substorms, Geotail, and Los Alamos National Laboratory spacecraft in geosynchronous orbit (16 spacecraft in total), we develop new insights on the nature of energetic particle injections associated with substorm activity. Despite this case involving only weak substorm activity (maximum AE <300 nT) during quiet geomagnetic conditions in steady, below-average solar wind, a complex series of at least sixmore » different electron injections was observed throughout the system. Intriguingly, only one corresponding ion injection was clearly observed. All ion and electron injections were observed at <600 keV only. MMS reveals detailed substructure within the largest electron injection. A relationship between injected electrons with energy <60 keV and enhanced whistler mode chorus wave activity is also established from Van Allen Probes and MMS. Drift mapping using a simplified magnetic field model provides estimates of the dispersionless injection boundary locations as a function of universal time, magnetic local time, and L shell. The analysis reveals that at least five electron injections, which were localized in magnetic local time, preceded a larger injection of both electrons and ions across nearly the entire nightside of the magnetosphere near geosynchronous orbit. The larger ion and electron injection did not penetrate to L < 6.6, but several of the smaller electron injections penetrated to L < 6.6. Due to the discrepancy between the number, penetration depth, and complexity of electron versus ion injections, this event presents challenges to the current conceptual models of energetic particle injections.« less

Multipoint Observations of Energetic Particle Injections and Substorm Activity During a Conjunction Between Magnetospheric Multiscale (MMS) and Van Allen Probes

DOE PAGES

Turner, Drew L.; Fennell, J. F.; Blake, J. B.; ...

2017-09-25

Here, this study examines multipoint observations during a conjunction between Magnetospheric Multiscale (MMS) and Van Allen Probes on 7 April 2016 in which a series of energetic particle injections occurred. With complementary data from Time History of Events and Macroscale Interactions during Substorms, Geotail, and Los Alamos National Laboratory spacecraft in geosynchronous orbit (16 spacecraft in total), we develop new insights on the nature of energetic particle injections associated with substorm activity. Despite this case involving only weak substorm activity (maximum AE <300 nT) during quiet geomagnetic conditions in steady, below-average solar wind, a complex series of at least sixmore » different electron injections was observed throughout the system. Intriguingly, only one corresponding ion injection was clearly observed. All ion and electron injections were observed at <600 keV only. MMS reveals detailed substructure within the largest electron injection. A relationship between injected electrons with energy <60 keV and enhanced whistler mode chorus wave activity is also established from Van Allen Probes and MMS. Drift mapping using a simplified magnetic field model provides estimates of the dispersionless injection boundary locations as a function of universal time, magnetic local time, and L shell. The analysis reveals that at least five electron injections, which were localized in magnetic local time, preceded a larger injection of both electrons and ions across nearly the entire nightside of the magnetosphere near geosynchronous orbit. The larger ion and electron injection did not penetrate to L < 6.6, but several of the smaller electron injections penetrated to L < 6.6. Due to the discrepancy between the number, penetration depth, and complexity of electron versus ion injections, this event presents challenges to the current conceptual models of energetic particle injections.« less

Feasibility study of low angle planetary entry. [probe design for Jovian entry

NASA Technical Reports Server (NTRS)

Defrees, R. E.

1975-01-01

The feasibility of a Jovian entry by a probe originally designed for Saturn and Uranus entries is examined. An entry probe is described which is capable of release near an outer planet's sphere of influence and descent to a predetermined target entry point in the planet's atmosphere. The probe is designed so as to survive the trapped particle radiation belts and an entry heating pulse. Data is gathered and relayed to an overflying spacecraft bus during descent. Probe variations for two similar missions are described. In the first flyby of Jupiter by a Pioneer spacecraft launched during the 1979 opportunity is examined parametrically. In the second mission an orbiter based on Pioneer and launched in 1980 is defined in specific terms. The differences rest in the science payloads and directly affected wiring and electronics packages.

Parker Solar Probe Spacecraft Arrival, Offload and Transport

NASA Image and Video Library

2018-04-03

A forklift operator latches onto the shipping container with NASA's Parker Solar Probe inside, after it was offloaded from a U.S. Air Force C-5 transport aircraft at Space Coast Regional Airport in Titusville, Florida. The spacecraft will be transported to the Astrotech processing facility near the agency's Kennedy Space Center. The Parker Solar Probe will launch on a United Launch Alliance Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida in July 2018. The mission will perform the closest-ever observations of a star when it travels through the Sun's atmosphere, called the corona. The probe will rely on measurements and imaging to revolutionize our understanding of the corona and the Sun-Earth connection.

KSC-03PD-3279

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers stand by as the balloon at right is released to lift the solar array panel into position for installation on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3275

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to attach the top of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3282

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, Dr. Francis Everitt, principal investigator, and Brad Parkinson, co-principal investigator, both from Stanford University, hold one of the small gyroscopes used in the Gravity Probe B spacecraft. The GP-B towers behind them. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3268

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base attach supports to a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3276

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to attach the top of a solar array panel onto the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3265

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the NASA spacecraft processing facility on North Vandenberg Air Force Base prepare to rotate the framework containing one of four solar panels to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3269

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. A worker in the NASA spacecraft processing facility on North Vandenberg Air Force Base adjust the supports on a solar array panel to be lifted and installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

KSC-03PD-3278

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the NASA spacecraft processing facility on North Vandenberg Air Force Base, a balloon gently lifts the solar array panel to be installed on the Gravity Probe B spacecraft. Installing each array is a 3-day process and includes a functional deployment test. The Gravity Probe B mission is a relativity experiment developed by NASAs Marshall Space Flight Center, Stanford University and Lockheed Martin. The spacecraft will test two extraordinary predictions of Albert Einsteins general theory of relativity that he advanced in 1916: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Gravity Probe B consists of four sophisticated gyroscopes that will provide an almost perfect space-time reference system. The mission will look in a precision manner for tiny changes in the direction of spin.

An Intelligent Pinger Network for Solid Glacier Environments

NASA Astrophysics Data System (ADS)

Schönitz, S.; Reuter, S.; Henke, C.; Jeschke, S.; Ewert, D.; Eliseev, D.; Heinen, D.; Linder, P.; Scholz, F.; Weinstock, L.; Wickmann, S.; Wiebusch, C.; Zierke, S.

2016-12-01

This talk presents a novel approach for an intelligent, agent-based pinger network in an extraterrestrial glacier environment. Because of recent findings of the Cassini spacecraft, a mission to Saturn's moon Enceladus is planned in order search for extraterrestrial life within the ocean beneath Enceladus' ice crust. Therefore, a maneuverable melting probe, the EnEx probe, was developed to melt into Enceladus' ice and take liquid samples from water-filled crevasses. Hence, the probe collecting the samples has to be able to navigate in ice which is a hard problem, because neither visual nor gravitational methods can be used. To enhance the navigability of the probe, a network of autonomous pinger units (APU) is in development that is able to extract a map of the ice environment via ultrasonic soundwaves. A network of these APUs will be deployed on the surface of Enceladus, melt into the ice and form a network to help guide the probe safely to its destination. The APU network is able to form itself fully autonomously and to compensate system failures of individual APUs. The agents controlling the single APU are realized by rule-based expert systems implemented in CLIPS. The rule-based expert system evaluates available information of the environment, decides for actions to take to achieve the desired goal (e.g. a specific network topology), and executes and monitors such actions. In general, it encodes certain situations that are evaluated whenever an APU is currently idle, and then decides for a next action to take. It bases this decision on its internal world model that is shared with the other APUs. The optimal network topology that defines each agents position is iteratively determined by mixed-integer nonlinear programming. Extensive simulations studies show that the proposed agent design enables the APUs to form a robust network topology that is suited to create a reliable 3D map of the ice environment.

Restoring Redundancy to the MAP Propulsion System

NASA Technical Reports Server (NTRS)

ODonnell, James R., Jr.; Davis, Gary T.; Ward, David K.; Bauer, F. (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe is a follow-on to the Differential Microwave Radiometer instrument on the Cosmic Background Explorer. Sixteen months before launch, it was discovered that from the time of the critical design review, configuration changes had resulted in a significant migration of the spacecraft's center of mass. As a result, the spacecraft no longer had a viable backup control mode in the event of a failure of the negative pitch axis thruster. Potential solutions to this problem were identified, such as adding thruster plume shields to redirect thruster torque, adding mass to, or removing it from, the spacecraft, adding an additional thruster, moving thrusters, bending thrusters (either nozzles or propellant tubing), or accepting the loss of redundancy for the thruster. The impacts of each solution, including effects on the mass, cost, and fuel budgets, as well as schedule, were considered, and it was decided to bend the thruster propellant tubing of the two roll control thrusters, allowing that pair to be used for back-up control in the negative pitch axis. This paper discusses the problem and the potential solutions, and documents the hardware and software changes that needed to be made to implement the chosen solution. Flight data is presented to show the propulsion system on-orbit performance.

Validation of double Langmuir probe in-orbit performance onboard a nano-satellite

NASA Astrophysics Data System (ADS)

Tejumola, Taiwo Raphael; Zarate Segura, Guillermo Wenceslao; Kim, Sangkyun; Khan, Arifur; Cho, Mengu

2018-03-01

Many plasma measurement systems have been proposed and used onboard different satellites to characterize space plasma. Most of these systems employed the technique of Langmuir probes either using the single or double probes methods. Recent growth of lean satellites has positioned it on advantage to be used for space science missions using Langmuir probes because of its simplicity and convenience. However, single Langmuir probes are not appropriate to be used on lean satellites because of their limited conducting area which leads to spacecraft charging and drift of the instrument's electrical ground during measurement. Double Langmuir probes technique can overcome this limitation, as a measurement reference in relation to the spacecraft is not required. A double Langmuir probe measurement system was designed and developed at Kyushu Institute of Technology for HORYU-IV satellite, which is a 10 kg, 30 cm cubic class lean satellite launched into Low Earth Orbit on 17th February 2016. This paper presents the on-orbit performance and validation of the double Langmuir probe measurement using actual on-orbit measured data and computer simulations.

Langmuir Probe Spacecraft Potential End Item Specification Document

NASA Technical Reports Server (NTRS)

Gilchrist, Brian; Curtis, Leslie (Technical Monitor)

2001-01-01

This document describes the Langmuir Probe Spacecraft Potential (LPSP) investigation of the plasma environment in the vicinity of the ProSEDS Delta II spacecraft. This investigation will employ a group of three (3) Langmuir Probe Assemblies, LPAs, mounted on the Delta II second stage to measure the electron density and temperature (n(sub e) and T(sub e)), the ion density (n(sub i)), and the spacecraft potential (V(sub s)) relative to the surrounding ionospheric plasma. This document is also intended to define the technical requirements and flight-vehicle installation interfaces for the design, development, assembly, testing, qualification, and operation of the LPSP subsystem for the Propulsive Small Expendable Deployer System (ProSEDS) and its associated Ground Support Equipment (GSE). This document also defines the interfaces between the LPSP instrument and the ProSEDS Delta II spacecraft, as well as the design, fabrication, operation, and other requirements established to meet the mission objectives. The LPSP is the primary measurement instrument designed to characterize the background plasma environment and is a supporting instrument for measuring spacecraft potential of the Delta II vehicle used for the ProSEDS mission. Specifically, the LPSP will use the three LPAs equally spaced around the Delta II body to make measurements of the ambient ionospheric plasma during passive operations to aid in validating existing models of electrodynamic-tether propulsion. These same probes will also be used to measure Delta II spacecraft potential when active operations occur. When the electron emitting plasma contractor is on, dense neutral plasma is emitted. Effective operation of the plasma contactor (PC) will mean a low potential difference between the Delta II second stage and the surrounding plasma and represents one of the voltage parameters needed to fully characterize the electrodynamic-tether closed circuit. Given that the LP already needs to be well away from any near-field disturbances around the Delta II, it is possible to use the same probe with a simple reconfiguration of the electronics to measure potential with respect to the ambient plasma. The LP measurement techniques are outlined in the following text and discussed in detail in the Appendix. The scientific goals of the investigation, the physical and electrical characteristics of the instrument, and the on-orbit measurement requirements are also discussed in this document.

Mars Observer Lecture: Mars Orbit Insertion

NASA Technical Reports Server (NTRS)

Dodd, Suzanne R. (Personal Name)

1993-01-01

The Mars Observer mission spacecraft was primarily designed for exploring Mars and the Martian environment. The Mars Observer was launched on September 25, 1992. The spacecraft was lost in the vicinity of Mars on August 21, 1993 when the spacecraft began its maneuvering sequence for Martian orbital insertion. This videotape shows a lecture by Suzanne R. Dodd, the Mission Planning Team Chief for the Mars Observer Project. Ms Dodd begins with a brief overview of the mission and the timeline from the launch to orbital insertion. Ms Dodd then reviews slides showing the trajectory of the spacecraft on its trip to Mars. Slides of the spacecraft being constructed are also shown. She then discusses the Mars orbit insertion and the events that will occur to move the spacecraft from the capture orbit into a mapping orbit. During the trip to Mars, scientists at JPL had devised a new strategy, called Power In that would allow for an earlier insertion into the mapping orbit. The talk summarizes this strategy, showing on a slide the planned transition orbits. There are shots of the Martian moon, Phobos, taken from the Viking spacecraft, as Ms Dodd explains that the trajectory will allow the orbiter to make new observations of that moon. She also explains the required steps to prepare for mapping after the spacecraft has achieved the mapping orbit around Mars. The lecture ends with a picture of Mars from the Observer on its approach to the planet.

Van Allen Probes Science Gateway: Single-Point Access to Long-Term Radiation Belt Measurements and Space Weather Nowcasting

NASA Astrophysics Data System (ADS)

Romeo, G.; Barnes, R. J.; Ukhorskiy, A. Y.; Sotirelis, T.; Stephens, G.

2017-12-01

The Science Gateway gives single-point access to over 4.5 years of comprehensive wave and particle measurements from the Van Allen Probes NASA twin-spacecraft mission. The Gateway provides a set of visualization and data analysis tools including: HTML5-based interactive visualization of high-level data products from all instrument teams in the form of: line plots, orbital content plots, dynamical energy spectra, L-shell context plots (including two-spacecraft plotting), FFT spectra of wave data, solar wind and geomagnetic indices data, etc.; download custom multi-instrument CDF data files of selected data products; publication quality plots of digital data; combined orbit predicts for mission planning and coordination including: Van Allen Probes, MMS, THEMIS, Arase (ERG), Cluster, GOES, Geotail, FIREBIRD; magnetic footpoint calculator for coordination with LEO and ground-based assets; real-time computation and processing of empirical magnetic field models - computation of magnetic ephemeris, computation of adiabatic invariants. Van Allen Probes is the first spacecraft mission to provide a nowcast of the radiation environment in the heart of the radiation belts, where the radiation levels are the highest and most dangerous for spacecraft operations. For this purpose, all instruments continuously broadcast a subset of their science data in real time. Van Allen Probes partners with four foreign institutions who operate ground stations that receive the broadcast: Korea (KASI), the Czech republic (CAS), Argentina (CONAE), and Brazil (INPE). The SpWx broadcast is then collected at APL and delivered to the community via the Science Gateway.

Design and spacecraft-integration of RTGs for solar probe

NASA Technical Reports Server (NTRS)

Schock, A.; Noravian, H.; Or, T.; Sankarankandath, V.

1990-01-01

The design, analysis, and spacecraft integration of radioisotope thermoelectric generators (RTG) to power the Solar Probe under study at NASA JPL is described. The mission of the Solar Probe is to explore the solar corona by performing in situ measurements at up to four solar radii to the sun. Design constraints for the RTG are discussed. The chief challenge in the design and system integration of the Solar Probe's RTG is a heat rejection problem. Two RTG orientations, horizontal and oblique, are analyzed for effectiveness and results are summarized in chart form. A number of cooling strategies are also investigated, including heat-pipe and reflector-cooled options. A methodology and general computer code are presented for analyzing the performance of arbitrarily obstructed RTGs with both axial and circumferential temperature, voltage, and current variation. This methodology is applied to the specific example of the Solar Probe RTG obstructed by a semicylindrical reflector of 15-inch radius.

Performance Evaluation of the Gravity Probe B Design

NASA Technical Reports Server (NTRS)

Francis, Ronnie; Wells, Eugene M.

1996-01-01

This report documents the simulation of the Lockheed Martin designed Gravity Probe B (GPB) spacecraft developed tool by bd Systems Inc using the TREETOPS simulation. This study quantifies the effects of flexibility and liquid helium slosh on GPB spacecraft control performance. The TREETOPS simulation tool permits the simulation of flexible structures given that a flexible body model of the structure is available. For purposes of this study, a flexible model of the GPB spacecraft was obtained from Lockheed Martin. To model the liquid helium slosh effects, computational fluid dynamics (CFD) results' were obtained, and used to develop a dynamic model of the slosh effects. The flexible body and slosh effects were incorporated separately into the TREETOPS simulation, which places the vehicle in a 650 km circular polar orbit and subjects the spacecraft to realistic environmental disturbances and sensor error quantities. In all of the analysis conducted in this study the spacecraft is pointed at an inertially fixed guide star (GS) and is rotating at a constant rate about this line of sight.

Galileo spacecraft power management and distribution system

NASA Technical Reports Server (NTRS)

Detwiler, R. C.; Smith, R. L.

1990-01-01

The Galileo PMAD (power management and distribution system) is described, and the design drivers that established the final as-built hardware are discussed. The spacecraft is powered by two general-purpose heat-source-radioisotope thermoelectric generators. Power bus regulation is provided by a shunt regulator. Galileo PMAD distributes a 570-W beginning of mission (BOM) power source to a user complement of some 137 load elements. Extensive use of pyrotechnics requires two pyro switching subassemblies. They initiate 148 squibs which operate the 47 pyro devices on the spacecraft. Detection and correction of faults in the Galileo PMAD is an autonomous feature dictated by requirements for long life and reliability in the absence of ground-based support. Volatile computer memories in the spacecraft command and data system and attitude control system require a continuous source of backup power during all anticipated power bus fault scenarios. Power for the Jupiter Probe is conditioned, isolated, and controlled by a Probe interface subassembly. Flight performance of the spacecraft and the PMAD has been successful to date, with no major anomalies.

Wilkinson Microwave Anisotropy Probe (WMAP) Attitude Estimation Filter Comparison

NASA Technical Reports Server (NTRS)

Harman, Richard R.

2005-01-01

The Wilkinson Microwave Anisotropy Probe (WMAP) spacecraft was launched in June of 2001. The sensor complement of WMAP consists of two Autonomous Star Trackers (ASTs), two Fine Sun Sensors (FSSs), and a gyro package which contains redundancy about one of the WMAP body axes. The onboard attitude estimation filter consists of an extended Kalman filter (EKF) solving for attitude and gyro bias errors which are then resolved into a spacecraft attitude quaternion and gyro bias. A pseudo-linear Kalman filter has been developed which directly estimates the spacecraft attitude quaternion, rate, and gyro bias. In this paper, the performance of the two filters is compared for the two major control modes of WMAP: inertial mode and observation mode.

Spacecraft Charging in Geostationary Transfer Orbit

NASA Technical Reports Server (NTRS)

Parker, Linda Neergaard; Minow, Joseph I.

2014-01-01

The 700 km x 5.8 Re orbit of the two Van Allen Probes spacecraft provide a unique opportunity to investigate spacecraft charging in geostationary transfer orbits. We use records from the Helium Oxygen Proton Electron (HOPE) plasma spectrometer to identify candidate surface charging events based on the "ion line" charging signature in the ion records. We summarize the energetic particle environment and the conditions necessary for charging to occur in this environment. We discuss the altitude, duration, and magnitude of events observed in the Van Allen Probes from the beginning of the mission to present time. In addition, we explore what information the dual satellites provide on the spatial and temporal variations in the charging environments.

The Future of NASA's Deep Space Network and Applications to Planetary Probe Missions

NASA Technical Reports Server (NTRS)

Deutsch, Leslie J.; Preston, Robert A.; Vrotsos, Peter

2010-01-01

NASA's Deep Space Network (DSN) has been an invaluable tool in the world's exploration of space. It has served the space-faring community for more than 45 years. The DSN has provided a primary communication pathway for planetary probes, either through direct- to-Earth links or through intermediate radio relays. In addition, its radiometric systems are critical to probe navigation and delivery to target. Finally, the radio link can also be used for direct scientific measurement of the target body ('radio science'). This paper will examine the special challenges in supporting planetary probe missions, the future evolution of the DSN and related spacecraft technology, the advantages and disadvantages of radio relay spacecraft, and the use of the DSN radio links for navigation and scientific measurements.

A Power Sailer Mission for a Jovian Orbiter and Trojan Asteroid Flybys

NASA Astrophysics Data System (ADS)

Kawaguchi, J.

The paper presents an innovative Solar Power Sail spacecraft mission that ushers the the century's new planetary explorations. The plan has been studied at ISAS/JAXA in Japan for the start of the project in very new future. The mission is defined as an engineering technology demonstrator, similar to the 'Hayabusa' (MUSES-C) that is currently flying toward an asteroid for a world's first sample-return attempt. The spacecraft studied here uses a world's first hybrid photon / ion propulsions taking the advantage of thin film photo-volatic technology. The mission has very new multi-purposes: First of all, the mission aims at flying-bys to the Trojan asteroids for the first time. And it is simply the first spacecraft to the Jupiter's distance powered only by solar cells. Utilizing the power surplus available at the Earth distance, the spacecraft is supposed to drive its ultra-high specific impulse ion engines aboard with the combination of the Earth gravity assist. The intended specific impulse will be 10,000 seconds, almost as 3.3 times efficient as existing contemporary ion engines. Not only the technology demonstration, in addition to the Trojan asteroid flybys, there are still more new innovative science purposes carried by this spacecraft. Among them, what should be emphasized is a background emission mapping excluding ecliptic dust cloud, which is cleared beyond four AU distance from the Sun. This will reveal the fundamental questions as to the extraordinary young stars observed only in deep IR region. Furthermore, this single spacecraft carries both a Jovian orbiter and an atmospheric reentry probe, both of which will constitute a spacious and simultaneous magnetoshere measurement at the Jovian polar region, via a formation flight. This is what has yet been tried so far in long solar planetary exploration history. ISAS/JAXA is now seriously investigating the spacecraft development and it may put a budgetary proposal for the start of the project hopefully very soon.

Labeled line drawing of Galileo spacecraft's atmospheric probe

NASA Technical Reports Server (NTRS)

1989-01-01

Labeled line drawing entitled GALILEO PROBE identifies the deceleration module aft cover, descent module, and deceleration module aeroshell configurations and dimensions prior to and during entry into Jupiter's atmosphere.

Labeled line drawing of Galileo spacecraft's atmospheric probe

NASA Image and Video Library

1989-09-11

Labeled line drawing entitled GALILEO PROBE identifies the deceleration module aft cover, descent module, and deceleration module aeroshell configurations and dimensions prior to and during entry into Jupiter's atmosphere.

Science aspects of a 1980 flyby of Comet Encke with a Pioneer spacecraft

NASA Technical Reports Server (NTRS)

Jaffe, L. D.; Elachi, C.; Giffin, C. E.; Huntress, W.; Newburn, R. L.; Parker, R. H.; Taylor, F. W.; Thorpe, T. E.

1974-01-01

Results are presented of an investigation of the feasibility of a 1980 flyby of Comet Encke using a Pioneer class spacecraft. Specific areas studied include: science objectives and rationale; science observables; effects of encounter velocity; science encounter and targeting requirements; selection and description of science instruments; definition of a candidate science payload; engineering characteristics of suggested payload; value of a separable probe; science instruments for a separable probe; science payload integration problems; and science operations profile.

Phillips with probe-and-cone docking mechanism (StM) in the Zvezda module

NASA Image and Video Library

2005-06-19

ISS011-E-09205 (19 June 2005) --- Astronaut John L. Phillips, Expedition 11 NASA ISS science officer and flight engineer, works on the dismantled probe-and-cone docking mechanism from the Progress 18 spacecraft in the Zvezda Service Module of the International Space Station (ISS). The Progress docked to the aft port of the Service Module at 7:42 p.m. (CDT) as the two spacecraft flew approximately 225 statute miles, above a point near Beijing, China.

Krikalev with probe-and-cone docking mechanism (StM) in the Zvezda module

NASA Image and Video Library

2005-06-19

ISS011-E-09210 (19 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, holds the dismantled probe-and-cone docking mechanism from the Progress 18 spacecraft in the Zvezda Service Module of the International Space Station (ISS). The Progress docked to the aft port of the Service Module at 7:42 p.m. (CDT) as the two spacecraft flew approximately 225 statute miles, above a point near Beijing, China.

System design of the Pioneer Venus spacecraft. Volume 5: Probe vehicle studies

NASA Technical Reports Server (NTRS)

Nolte, L. J.; Stephenson, D. S.

1973-01-01

A summary of the key issues and studies conducted for the Pioneer Venus spacecraft and the resulting probe designs are presented. The key deceleration module issues are aerodynamic configuration and heat shield material selection. The design and development of the pressure vessel module are explained. Thermal control and science integration of the pressure vessel module are explained. The deceleration module heat shield, parachute and separation/despin are reported. The Thor/Delta and Atlas/Centaur baseline descriptions are provided.

Remote laser evaporative molecular absorption spectroscopy

NASA Astrophysics Data System (ADS)

Hughes, Gary B.; Lubin, Philip; Cohen, Alexander; Madajian, Jonathan; Kulkarni, Neeraj; Zhang, Qicheng; Griswold, Janelle; Brashears, Travis

2016-09-01

We describe a novel method for probing bulk molecular and atomic composition of solid targets from a distant vantage. A laser is used to melt and vaporize a spot on the target. With sufficient flux, the spot temperature rises rapidly, and evaporation of surface materials occurs. The melted spot creates a high-temperature blackbody source, and ejected material creates a plume of surface materials in front of the spot. Molecular and atomic absorption occurs as the blackbody radiation passes through the ejected plume. Bulk molecular and atomic composition of the surface material is investigated by using a spectrometer to view the heated spot through the ejected plume. The proposed method is distinct from current stand-off approaches to composition analysis, such as Laser-Induced Breakdown Spectroscopy (LIBS), which atomizes and ionizes target material and observes emission spectra to determine bulk atomic composition. Initial simulations of absorption profiles with laser heating show great promise for Remote Laser-Evaporative Molecular Absorption (R-LEMA) spectroscopy. The method is well-suited for exploration of cold solar system targets—asteroids, comets, planets, moons—such as from a spacecraft orbiting the target. Spatial composition maps could be created by scanning the surface. Applying the beam to a single spot continuously produces a borehole or trench, and shallow subsurface composition profiling is possible. This paper describes system concepts for implementing the proposed method to probe the bulk molecular composition of an asteroid from an orbiting spacecraft, including laser array, photovoltaic power, heating and ablation, plume characteristics, absorption, spectrometry and data management.

GRAIL Mission Comes Together

NASA Image and Video Library

2011-08-18

NASA twin Gravity Recovery and Interior Laboratory GRAIL spacecraft are lowered onto the second stage of their Delta II launch vehicle. At top is the spacecraft adapter ring which holds the two lunar probes in their side-by-side launch configuration.

Nitrogen Isotopic Ratio in Jupiter's Atmosphere from Observations by Composite Infrared Spectrometer (CIRS) on the Cassini Spacecraft

NASA Technical Reports Server (NTRS)

Abbas, M. M.; LeClair, A.; Owen, T.; Conrath, B. J.; Flasar, F. M.; Kunde, V. G.; Nixon, C. A..; Achterberg, R. K.; Bjoraker, G.; Jennings, D. J.

2003-01-01

The Composite Infrared Spectrometer (CIRS) on the Cassini spacecraft made infrared observations of Jupiter's atmosphere during the flyby in December 2000 to January 2001. The unique database in the 600-1400/cm region with 0.53 and 2.8/cm spectral resolutions obtained from the observations permits retrieval of global maps of the thermal structure and composition of Jupiter's atmosphere including the distributions of (14)NH3 and (15)NH3. Analysis of Jupiter's ammonia distributions from three isolated (15)NH3 spectral lines in eight latitudes is presented for evaluation of the nitrogen isotopic ratio. The nitrogen isotopic ratio (14)N/(15)N (or (15)N/(14)N) in Jupiter's atmosphere in this analysis is calculated to be: 448 +/- 62 ((2.23 +/- 0.31) x 10(exp -3)). This value of the ratio determined from CIRS data is found to be in very close agreement with the value previously obtained from the measurements by the Galileo Probe Mass Spectrometer. Some possible mechanisms to account for the variation of Jupiter's observed isotopic ratio relative to various astrophysical environments are discussed.

Recovery of time evolution of Grad-Shafranov equilibria from single-spacecraft data: Benchmarking and application to a flux transfer event

NASA Astrophysics Data System (ADS)

Hasegawa, Hiroshi; Sonnerup, Bengt U. Ã.-.; Nakamura, Takuma K. M.

2010-11-01

First results are presented of a method, developed by Sonnerup and Hasegawa (2010), for analyzing time evolution of magnetohydrostatic Grad-Shafranov (GS) equilibria, using data recorded by an observing probe as it traverses a quasi-static, two-dimensional (2D), magnetic-field/plasma structure. The method recovers spatial initial values used in the classical GS reconstruction for an interval before and after the time of actual measurements, by advancing them backward and forward in time based on a set of equations for an incompressible plasma; the consequence is generation of multiple GS maps or a movie of the 2D field structure. The method is successfully benchmarked by use of a 2D magnetohydrodynamic simulation of time-dependent magnetic reconnection, and then is applied to a flux transfer event (FTE) seen by the Cluster spacecraft at the dayside high-latitude magnetopause. The application shows that the field lines constituting the FTE flux rope were contracting toward its center as a result of modest convective flow in the region around the core of the flux rope.

Rationale and concept for a lunar pit reconnaissance probe

NASA Astrophysics Data System (ADS)

Dorrington, G. E.

2018-04-01

Speculation on near-term scientific reasons for the exploration of lunar pits is offered alongside comments on possible longer-term human exploitation. It is proposed that in order to determine whether or not one or more of the pits offer access the large subsurface voids e.g. a non-collapsed lava tube, a preliminary reconnaissance mission solely focused on obtaining lateral images (and/or LiDAR maps) is needed. Possible concept options for such a preliminary reconnaissance mission are discussed. It is suggested that one of the best possible strategies is to employ a micro-sized probe (∼0.3m) that would hop from a nearby main landing spacecraft to the selected pit. After the surface position of the main lander is determined accurately, the probe would perform a ballistic hop, or hover-traverse, a distance of ∼3 km over the lunar surface using existing propulsive and guidance technology capability. Once hovering above the pit, the probe or a separate tethered imaging unit would then be lowered into the pit to acquire the necessary subsurface void topology data. This data would then be transmitted back to Earth, directly, via the lander, or via a store-and-forward orbiting relay. Preliminary estimates indicate that a probe of ∼14 kg (dry mass) is viable using a conventional hydrazine monopropellant system with a propellant mass fraction of less than ∼0.2 (20%) including margins, suggesting a piggyback architecture would be feasible.

Gravity Probe B

NASA Image and Video Library

2003-07-12

Enclosed in a canister, the Gravity Probe B (GP-B) spacecraft arrives on Vandenberg Air Force Base, headed for the spacecraft processing facility. Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einstein’s general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Once in orbit, for 18 months each gyroscope’s spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASA’s Marshall Space Flight Center.

Charging of the Van Allen Probes: Theory and Simulations

NASA Astrophysics Data System (ADS)

Delzanno, G. L.; Meierbachtol, C.; Svyatskiy, D.; Denton, M.

2017-12-01

The electrical charging of spacecraft has been a known problem since the beginning of the space age. Its consequences can vary from moderate (single event upsets) to catastrophic (total loss of the spacecraft) depending on a variety of causes, some of which could be related to the surrounding plasma environment, including emission processes from the spacecraft surface. Because of its complexity and cost, this problem is typically studied using numerical simulations. However, inherent unknowns in both plasma parameters and spacecraft material properties can lead to inaccurate predictions of overall spacecraft charging levels. The goal of this work is to identify and study the driving causes and necessary parameters for particular spacecraft charging events on the Van Allen Probes (VAP) spacecraft. This is achieved by making use of plasma theory, numerical simulations, and on-board data. First, we present a simple theoretical spacecraft charging model, which assumes a spherical spacecraft geometry and is based upon the classical orbital-motion-limited approximation. Some input parameters to the model (such as the warm plasma distribution function) are taken directly from on-board VAP data, while other parameters are either varied parametrically to assess their impact on the spacecraft potential, or constrained through spacecraft charging data and statistical techniques. Second, a fully self-consistent numerical simulation is performed by supplying these parameters to CPIC, a particle-in-cell code specifically designed for studying plasma-material interactions. CPIC simulations remove some of the assumptions of the theoretical model and also capture the influence of the full geometry of the spacecraft. The CPIC numerical simulation results will be presented and compared with on-board VAP data. This work will set the foundation for our eventual goal of importing the full plasma environment from the LANL-developed SHIELDS framework into CPIC, in order to more accurately predict spacecraft charging.

The Hera Saturn entry probe mission

NASA Astrophysics Data System (ADS)

Mousis, O.; Atkinson, D. H.; Spilker, T.; Venkatapathy, E.; Poncy, J.; Frampton, R.; Coustenis, A.; Reh, K.; Lebreton, J.-P.; Fletcher, L. N.; Hueso, R.; Amato, M. J.; Colaprete, A.; Ferri, F.; Stam, D.; Wurz, P.; Atreya, S.; Aslam, S.; Banfield, D. J.; Calcutt, S.; Fischer, G.; Holland, A.; Keller, C.; Kessler, E.; Leese, M.; Levacher, P.; Morse, A.; Muñoz, O.; Renard, J.-B.; Sheridan, S.; Schmider, F.-X.; Snik, F.; Waite, J. H.; Bird, M.; Cavalié, T.; Deleuil, M.; Fortney, J.; Gautier, D.; Guillot, T.; Lunine, J. I.; Marty, B.; Nixon, C.; Orton, G. S.; Sánchez-Lavega, A.

2016-10-01

The Hera Saturn entry probe mission is proposed as an M-class mission led by ESA with a contribution from NASA. It consists of one atmospheric probe to be sent into the atmosphere of Saturn, and a Carrier-Relay spacecraft. In this concept, the Hera probe is composed of ESA and NASA elements, and the Carrier-Relay Spacecraft is delivered by ESA. The probe is powered by batteries, and the Carrier-Relay Spacecraft is powered by solar panels and batteries. We anticipate two major subsystems to be supplied by the United States, either by direct procurement by ESA or by contribution from NASA: the solar electric power system (including solar arrays and the power management and distribution system), and the probe entry system (including the thermal protection shield and aeroshell). Hera is designed to perform in situ measurements of the chemical and isotopic compositions as well as the dynamics of Saturn's atmosphere using a single probe, with the goal of improving our understanding of the origin, formation, and evolution of Saturn, the giant planets and their satellite systems, with extrapolation to extrasolar planets. Hera's aim is to probe well into the cloud-forming region of the troposphere, below the region accessible to remote sensing, to the locations where certain cosmogenically abundant species are expected to be well mixed. By leading to an improved understanding of the processes by which giant planets formed, including the composition and properties of the local solar nebula at the time and location of giant planet formation, Hera will extend the legacy of the Galileo and Cassini missions by further addressing the creation, formation, and chemical, dynamical, and thermal evolution of the giant planets, the entire solar system including Earth and the other terrestrial planets, and formation of other planetary systems.

Solar Probe thermal shield design and testing

NASA Technical Reports Server (NTRS)

Millard, Jerry M.; Miyake, Robert N.; Rainen, Richard A.

1992-01-01

This paper discusses the major thermal shield subsystem development activities in support of the Solar Probe study being conducted at JPL. The Solar Probe spacecraft will travel to within 4 solar radii of the sun's center to perform fundamental experiments in space physics. Exposure to 2900 earth suns at perihelion requires the spacecraft to be protected within the shadow envelope of a protective shield. In addition, the mass loss rate off of the shield at elevated temperature must comply with plasma instrument requirements and has become the driver of the shield design. This paper will focus on the analytical design work to size the shield and control the shield mass loss rate for the various spacecraft options under study, the application of carbon-carbon materials for shield components, development and preparation of carbon-carbon samples for materials testing, and a materials testing program for carbon-carbon and tungsten alloys to investigate thermal/optical properties, mass loss (carbon-carbon only), material integrity, and high velocity impact behavior.

Voss with docking probe in Service module

NASA Image and Video Library

2001-05-30

ISS002-E-6478 (30 May 2001) --- James S. Voss, Expedition Two flight engineer, handles a spacecraft docking probe in the Service Module. The docking probe assists with the docking of the Soyuz and Progress vehicles to the International Space Station. The image was taken with a digital still camera.

KENNEDY SPACE CENTER, FLA. - This seal illustrates the mission of the Gravity Probe B spacecraft and the organizations who developed the experiment: Stanford University, NASA’s Marshall Space Flight Center and Lockheed Martin. The Gravity Probe B mission will test the theory of curved spacetime and "frame-dragging," depicted graphically in the lower half, that was developed by Einstein and other scientists. Above the graphic is a drawing of GP-B circling the Earth.

NASA Image and Video Library

2003-10-30

KENNEDY SPACE CENTER, FLA. - This seal illustrates the mission of the Gravity Probe B spacecraft and the organizations who developed the experiment: Stanford University, NASA’s Marshall Space Flight Center and Lockheed Martin. The Gravity Probe B mission will test the theory of curved spacetime and "frame-dragging," depicted graphically in the lower half, that was developed by Einstein and other scientists. Above the graphic is a drawing of GP-B circling the Earth.

Van Allen Probe Charging During the St. Patrick's Day Event

NASA Technical Reports Server (NTRS)

Parker, L. Neergaard; Minow, J. I.

2015-01-01

The geomagnetic storms on and around March 17, 2015 marked the largest storms seen in the declining phase of the solar cycle to date. We use the Helium Oxygen Proton Electron (HOPE) mass spectrometer on board the Van Allen Probe - A and B satellites to study in detail the charging effects seen on these spacecraft during this time. Ion particle flux data provides information on the magnitude of the charging events using the ion line charging signature due to low energy ions accelerated by the spacecraft potential. Electron flux observations are used to correlate the charging environment with variations in spacecraft potential through the event. We also investigate the density and temperature of ions and electrons during the time of the charging event.

The Hera Saturn Entry Probe Mission: a Proposal in Response to the ESA M5 Call

NASA Astrophysics Data System (ADS)

Mousis, Olivier; Atkinson, David; Amato, Michael; Aslam, Shahid; Atreya, Sushil; Blanc, Michel; Bolton, Scott; Brugger, Bastien; Calcutt, Simon; Cavalié, Thibault; Charnoz, Sébastien; Coustenis, Athena; Deleuil, Magali; Dobrijevic, Michel; Ferri, Francesca; Fletcher, Leigh; Gautier, Daniel; Guillot, Tristan; Hartogh, Paul; Holland, Andrew

2017-04-01

The Hera Saturn entry probe mission is proposed as an ESA M-class mission to be piggybacked on a NASA spacecraft sent to or past the Saturn system. Hera consists of an atmospheric probe built by ESA and released into the atmosphere of Saturn by its NASA companion Saturn Carrier-Relay spacecraft. Hera will perform in situ measurements of the chemical and isotopic composition as well as the structure and dynamics of Saturn's atmosphere using a single probe, with the goal of improving our understanding of the origin, formation, and evolution of Saturn, the giant planets and their satellite systems, with extrapolation to extrasolar planets. Hera will probe well into and possibly beneath the cloud-forming region of the troposphere, below the region accessible to remote sensing, to locations where certain cosmogenically abundant species are expected to be well mixed. The Hera probe will be designed from ESA elements with possible contributions from NASA, and the Saturn/Carrier-Relay Spacecraft will be supplied by NASA through its selection via the New Frontier 2016 call or in the form of a flagship mission selected by the NASA "Roadmaps to Ocean Worlds" (ROW) program. The Hera probe will be powered by batteries, and we therefore anticipate only one major subsystems to be possibly supplied by the United States, either by direct procurement by ESA or by contribution from NASA: the thermal protection system of the probe. Following the highly successful example of the Cassini-Huygens mission, Hera will carry European and American instruments, with scientists and engineers from both agencies and many affiliates participating in all aspects of mission development and implementation. A Saturn probe is one of the six identified desired themes by the Planetary Science Decadal Survey committee on the NASA New Frontier's list, providing additional indication that a Saturn probe is of extremely high interest and a very high priority for the international community.

Magnet-Based System for Docking of Miniature Spacecraft

NASA Technical Reports Server (NTRS)

Howard, Nathan; Nguyen, Hai D.

2007-01-01

A prototype system for docking a miniature spacecraft with a larger spacecraft has been developed by engineers at the Johnson Space Center. Engineers working on Mini AERCam, a free-flying robotic camera, needed to find a way to successfully dock and undock their miniature spacecraft to refuel the propulsion and recharge the batteries. The subsystems developed (see figure) include (1) a docking port, designed for the larger spacecraft, which contains an electromagnet, a ball lock mechanism, and a service probe; and (2) a docking cluster, designed for the smaller spacecraft, which contains either a permanent magnet or an electromagnet. A typical docking operation begins with the docking spacecraft maneuvering into position near the docking port on the parent vehicle. The electromagnet( s) are then turned on, and, if necessary, the docking spacecraft is then maneuvered within the capture envelope of the docking port. The capture envelope for this system is approximated by a 5-in. (12.7-cm) cube centered on the front of the docking-port electromagnet and within an angular misalignment of <30 . Thereafter, the magnetic forces draw the smaller spacecraft toward the larger one and this brings the spacecraft into approximate alignment prior to contact. Mechanical alignment guides provide the final rotational alignment into one of 12 positions. Once the docking vehicle has been captured magnetically in the docking port, the ball-lock mechanism is activated, which locks the two spacecraft together. At this point the electromagnet( s) are turned off, and the service probe extended if recharge and refueling are to be performed. Additionally, during undocking, the polarity of one electromagnet can be reversed to provide a gentle push to separate the two spacecraft. This system is currently being incorporated into the design of Mini AERCam vehicle.

Outer planet entry probe system study. Volume 1: Summary

NASA Technical Reports Server (NTRS)

1972-01-01

General mission considerations and science prospectus, which are of a general nature that applies to several or all planetary applications, are presented. Five probe systems are defined: nominal Jupiter probe system, and Jupiter probe-dedicated alternative probe system, Jupiter spacecraft radiation-compatible alternative probe system, Saturn probe system, and Saturn probe applicability for Uranus. Parametric analysis is summarized for mission analysis of a general nature, and then for specific missions to Jupiter, Saturn, Uranus, and Neptune. The program is also discussed from the hardware availability viewpoint and the aspect of commonality.

Mapping the Galilean moon’s disturbance acting on a spacecraft’s trajectory

NASA Astrophysics Data System (ADS)

Camargo de Araujo, Natasha; Marconi Rocco, Evandro

2017-10-01

The prime objective of this work is to map the disturbance of Jupiter’s Galilean moons, Io, Europa, Ganymede and Callisto, on a spacecraft trajectory. The study is done using an orbital trajectory simulator, the STRS (Spacecraft Trajectory Simulator). This mapping is made first considering the four moons as a group, and after that the disturbances of each of the Galilean moons are considered individually.

Gravity Probe-B (GP-B) Mission and Tracking, Telemetry and Control Subsystem Overview

NASA Technical Reports Server (NTRS)

Kennedy, Paul; Bell, Joseph L. (Technical Monitor)

2001-01-01

The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) in Huntsville, Alabama will launch the Gravity Probe B (GP-B) space experiment in the Fall of 2002. The GP-B spacecraft was developed to prove Einstein's theory of General Relativity. This paper will provide an overview of the GPB mission and will discuss the design, and test of the spacecraft Tracking, Telemetry and Control (TT&C) subsystem which incorporates NASA's latest generation standard transponder for use with the NASA Tracking and Data Relay Satellite System (TDRSS).

KSC-97PC1363

NASA Image and Video Library

1997-09-08

Workers remove the Huygens probe from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Further internal inspection, insulation repair and a cleaning of the probe are now required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1392

NASA Image and Video Library

1997-09-10

Jet Propulsion Laboratory (JPL) workers examine the Huygens probe after removal from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1360

NASA Image and Video Library

1997-09-08

Jet Propulsion Laboratory (JPL) workers remove the Huygens probe from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Further internal inspection, insulation repair and a cleaning of the probe are now required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1362

NASA Image and Video Library

1997-09-08

Workers remove the Huygens probe from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Further internal inspection, insulation repair and a cleaning of the probe are now required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1361

NASA Image and Video Library

1997-09-08

Workers remove the Huygens probe from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Further internal inspection, insulation repair and a cleaning of the probe are now required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

Plume Characteristics of the BHT-HD-600 Hall Thruster (Preprint)

DTIC Science & Technology

2006-07-01

Hall thruster on spacecraft, a number of plume properties have been measured. These include current density using a Faraday probe, ion energy distribution using a retarding potential analyzer, and ion species fractions using an E x B probe. The BHT-HD-600 Hall thruster is a nominally 600 W xenon Hall thruster developed by Busek Co. Inc. for the U.S. Air Force Research Laboratory. Plume characterization of Hall thrusters is required to fully understand the impacts of thruster operation on spacecraft. Much of these plume data are

Solar probe shield developmental testing

NASA Technical Reports Server (NTRS)

Miyake, Robert N.

1991-01-01

The objectives of the Solar Probe mission and the current status of the Solar Probe thermal shield subsystem development are described. In particular, the discussion includes a brief description of the mission concepts, spacecraft configuration and shield concept, material selection criteria, and the required material testing to provide a database to support the development of the shield system.

Spacecraft-environment interaction model cross comparison applied to Solar Probe Plus

NASA Astrophysics Data System (ADS)

Lapenta, G.; Deca, J.; Markidis, S.; Marchand, R.; Guillemant, S.; Matéo Vélez, J.; Miyake, Y.; Usui, H.; Ergun, R.; Sturner, A. P.

2013-12-01

Given that our society becomes increasingly dependent on space technology, it is imperative to develop a good understanding of spacecraft-plasma interactions. Two main issues are important. First, one needs to be able to design a reliable spacecraft that can survive in the harsh solar wind conditions, and second a very good knowledge of the behaviour and plasma structure around the spacecraft is required to be able to interpret and correct measurements from onboard instruments and science experiments. In this work we present the results of a cross-comparison study between five spacecraft-plasma models (EMSES, iPic3D, LASP, PTetra, SPIS) used to simulate the interaction of the Solar Probe Plus (SPP) satellite with the space environment under representative solar wind conditions near perihelion. The purpose of this cross-comparison is to assess the consistency and validity of the different numerical approaches from the similarities and differences of their predictions under well defined conditions, with attention to the implicit PIC code iPic3D, which has never been used for spacecraft-environment interaction studies before. The physical effects considered are spacecraft charging, photoelectron and secondary electron emission, the presence of a background magnetic field and density variations. The latter of which can cause the floating potential of SPP to go from negative to positive or visa versa, depending on the solar wind conditions, and spacecraft material properties. Simulation results are presented and compared with increasing levels of complexity in the physics to evaluate the sensitivity of the model predictions to certain physical effects. The comparisons focus particularly on spacecraft floating potential, detailed contributions to the currents collected and emitted by the spacecraft, and on the potential and density spatial profiles near the satellite. Model predictions obtained with our different computational approaches are found to be in good agreement when the physical processes are treated similarly. The comparisons considered here indicate that, with the correct parameterization of important physical effects such as photoemission and secondary electron emission, our simulation models should have the required skill to predict details of satellite-plasma interaction physics with a high level of confidence. This work was supported by the International Space Science Institute in Bern Switzerland. The potential profile around the Solar Probe Plus spacecraft in orbital flow, from the iPic3D code. The physical model includes photo- and secondary electrons and a static magnetic field.

Automated bow shock and radiation belt edge identification methods and their application for Cluster, THEMIS/ARTEMIS and Van Allen Probes data

NASA Astrophysics Data System (ADS)

Facsko, Gabor; Sibeck, David; Balogh, Tamas; Kis, Arpad; Wesztergom, Viktor

2017-04-01

The bow shock and the outer rim of the outer radiation belt are detected automatically by our algorithm developed as a part of the Boundary Layer Identification Code Cluster Active Archive project. The radiation belt positions are determined from energized electron measurements working properly onboard all Cluster spacecraft. For bow shock identification we use magnetometer data and, when available, ion plasma instrument data. In addition, electrostatic wave instrument electron density, spacecraft potential measurements and wake indicator auxiliary data are also used so the events can be identified by all Cluster probes in highly redundant way, as the magnetometer and these instruments are still operational in all spacecraft. The capability and performance of the bow shock identification algorithm were tested using known bow shock crossing determined manually from January 29, 2002 to February 3,. The verification enabled 70% of the bow shock crossings to be identified automatically. The method shows high flexibility and it can be applied to observations from various spacecraft. Now these tools have been applied to Time History of Events and Macroscale Interactions during Substorms (THEMIS)/Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) magnetic field, plasma and spacecraft potential observations to identify bow shock crossings; and to Van Allen Probes supra-thermal electron observations to identify the edges of the radiation belt. The outcomes of the algorithms are checked manually and the parameters used to search for bow shock identification are refined.

The 1981 Goddard Space Flight Center Battery Workshop

NASA Technical Reports Server (NTRS)

Halpert, G. (Editor)

1982-01-01

Results of testing, analysis, and development of lithium, nickel-cadmium, and nickel-hydrogen batteries are reported. Focus is on the improvement of power systems in the areas of high capacity, high energy density, and long cycle and storage life. Applications of these batteries as spacecraft power supplies are discussed. Those spacecraft include deepspace probes, spacecraft in geostationary orbit, and large space systems in low-Earth orbit.

Project Helios-A. [mission planning for solar probe

NASA Technical Reports Server (NTRS)

1974-01-01

The Helios-A solar probe which will fly within 28 million miles of the sun is described as a joint American and German project. The spacecraft and instrument designs, planned experiments, and mission are briefly discussed.

Kilometer-Scale Transient Atmospheres for Kinetic Payload Deposition on Icy Bodies

NASA Astrophysics Data System (ADS)

Koch, James

Entry, descent, and landing technologies for space exploration missions to atmospheric bodies traditionally exploit the body's ambient atmosphere as a medium through which a spacecraft or probe can interact to transfer momentum and energy for a soft landing. For bodies with no appreciable atmosphere, a significant engineering challenge exists to overcome the lack of passive methods to decelerate a spacecraft or probe. Proposed is a novel means for the creation of a transient atmosphere for airless icy bodies through the use of a two stage payload-penetrator probe. The first stage is a hyper-velocity penetrator that impacts the icy body. The second stage is an aero-braking-capable probe directed to pass through the ejecta plume from the hyper-velocity impact. Both experimental and computational studies show that a controlled high-energy impact can direct and transfer energy and momentum to a probe via a collimated ejecta plume. In an effort to provide clarity to this unexplored class of missions, a modeling-based engineering approach is taken to provide a first-order estimation of some of the involved physical phenomena. Three sub-studies are presented: an examination and characterization of ice plumes, modeling plume-probe interaction, and the extension of plume modeling as the basis for conceptual mission design. The modeling efforts are centered about two modeling formulations: smoothed particle hydrodynamics (SPH) and the arbitrary Largrangian-Eulerian (ALE) set of techniques. A database of fully-developed hypervelocity impacts and their associated plumes is created and used as inputs to a 1-D mathematical model for the interaction of a continuum-based plume and probe. A parametric study based on the hyper-velocity impact and staging of the probe-penetrator system is presented and discussed. Shown is that a tuned penetrator-probe mission has the potential to increase spacecraft payload mass fraction over conventional soft landing schemes.

Solar Probe Plus MAG Sensor Thermal Design for Low Heater Power and Extreme Thermal Environment

NASA Technical Reports Server (NTRS)

Choi, Michael K.

2015-01-01

The heater power available for the Solar Probe Plus FIELDS MAG sensor is less than half of the heritage value for other missions. Nominally the MAG sensors are in the spacecraft's umbra. In the worst hot case, approximately 200 spacecraft communication downlinks, up to 10 hours each, are required at 0.7 AU. These downlinks require the spacecraft to slew 45 deg. about the Y-axis, exposing the MAG sensors and boom to sunlight. This paper presents the thermal design to meet the MAG sensor thermal requirements in the extreme thermal environment and with low heater power. A thermal balance test on the MAG sensor engineering model has verified the thermal design and correlated the thermal model for flight temperature predictions.

System design of the Pioneer Venus spacecraft. Volume 3: Systems analysis

NASA Technical Reports Server (NTRS)

Fisher, J. N.

1973-01-01

The mission, systems, operations, ground systems, and reliability analysis of the Thor/Delta baseline design used for the Pioneer Space Probe are discussed. Tradeoff decisions concerning spin axis orientation, bus antenna design, communication system design, probe descent, and reduced science payload are analyzed. The reliability analysis is made for the probe bus mission, large probe mission, and small probe mission. Detailed mission sequences were established to identify critical areas and provide phasing of critical operation.

Data catalog series for space science and applications flight missions. Volume 1A: Brief descriptions of planetary and heliocentric spacecraft and investigations

NASA Technical Reports Server (NTRS)

Cameron, W. S. (Editor); Vostreys, R. W. (Editor)

1982-01-01

Planetary and heliocentric spacecraft, including planetary flybys and probes, are described. Imaging, particles and fields, ultraviolet, infrared, radio science and celestial mechanics, atmospheres, surface chemistry, biology, and polarization are discussed.

ScienceCast 76: The Radiation Belt Storm Probes

NASA Image and Video Library

2012-08-30

This morning NASA launched two heavily-shielded spacecraft directly into the Van Allen Belts. The Radiation Belt Storm Probes are on a two-year mission to study the Van Allen Belts and to unravel the mystery of their unpredictability.

Cassini/Huygens Science Instruments, Spacecraft, and Mission

NASA Technical Reports Server (NTRS)

Jaffe, Leonard D.; Herrell, Linda M.

1997-01-01

The Cassini spacecraft will take 18 scientific instruments to Saturn. After launch and a seven-year cruise, Cassini will arrive at Saturn and separate into a Saturn orbiter and an atmospheric probe, called Huygens, which will descend to the surface of Titan. The orbiter will orbit the planet for four years, making close flybys of five satellites, including multiple flybys of Titan. Communication with Earth is at X-band; the maximum downlink rate from Saturn is 166 x 10(exp 3) bps. Orbiter instruments are body mounted; the spacecraft must be turned to point some of them toward objects of interest. The orbiter carries 12 instruments. Optical instruments provide imagery and spectrometry. Radar supplies imaging, altimetry, and radiometry. Radio links contribute information about intervening material and gravity fields. Other instruments measure electromagnetic fields and the properties of plasma, energetic particles, and dust particles. The probe is spin stabilized. It returns data via an S-band link to the orbiter. The probe's six instruments include sensors to determine atmospheric physical properties and composition. Radiometric and optical sensors will produce data on thermal balance and obtain images of Titan's atmosphere and surface. Doppler measurements between probe and orbiter will provide wind profiles. Surface sensors will measure impact acceleration, thermal and electrical properties, and, if the surface is liquid, density and refractive index. This design will enable Cassini to determine the composition; the physical, morphological, and geological nature; and the physical and chemical processes of the atmospheres, surfaces, and magnetosphere of the Saturnian system. This paper briefly describes the Cassini mission and spacecraft and, in somewhat more detail, the scientific instruments.

NASA names unique solar mission after University of Chicago physicist Eugene Parker

NASA Image and Video Library

2017-05-31

On May 31, NASA renamed humanity’s first mission to fly a spacecraft directly into the sun’s atmosphere in honor of Professor Eugene Parker, a pioneering physicist at the University of Chicago. This is the first time in agency history a spacecraft has been named for a living individual. Parker, the S. Chandrasekhar Distinguished Service Professor Emeritus in Physics, is best known for developing the concept of solar wind—the stream of electrically charged particles emitted by the sun. Previously named Solar Probe Plus, the Parker Solar Probe will launch in summer 2018. Placed in orbit within four million miles of the sun’s surface, and facing heat and radiation unlike any spacecraft in history, the spacecraft will explore the sun’s outer atmosphere and make critical observations that will answer decades-old questions about the physics of how stars work. The resulting data will improve forecasts of major space weather events that impact life on Earth, as well as satellites and astronauts in space.

Mariner 9 mapping science sequence design.

NASA Technical Reports Server (NTRS)

Goldman, A. M., Jr.

1973-01-01

The primary mission of Mariner 9 was to map the Martian surface. This paper discusses in detail the design of the mapping science sequences which were executed by the spacecraft in sixty days and during which over eighty percent of the surface was photographed. The sequence design was influenced by many factors: experimenter scientific objectives, instrument capabilities, spacecraft capabilities, orbit characteristics, and data return rates, which are illustrated graphically. Typical orbits are depicted for each of the three different mapping phases lasting twenty days. Examples of typical orbital sequence plans prepared daily during mission operations are given.

Mapping Pluto Methane Ice

NASA Image and Video Library

2015-09-24

The Ralph/LEISA infrared spectrometer on NASA's New Horizons spacecraft mapped compositions across Pluto's surface as it flew past the planet on July 14, 2015. On the left, a map of methane ice abundance shows striking regional differences, with stronger methane absorption indicated by the brighter purple colors, and lower abundances shown in black. Data have only been received so far for the left half of Pluto's disk. At right, the methane map is merged with higher-resolution images from the spacecraft's Long Range Reconnaissance Imager (LORRI). http://photojournal.jpl.nasa.gov/catalog/PIA19953

Van Allen Probes observations of intense parallel Poynting flux associated with magnetic dipolarization, conjugate discrete auroral arcs, and energetic particle injection

NASA Astrophysics Data System (ADS)

Wygant, J. R.; Thaller, S. A.; Breneman, A. W.; Tian, S.; Cattell, C. A.; Chaston, C. C.; Mozer, F.; Bonnell, J. W.; Kistler, L. M.; Mouikis, C.; Hudson, M. K.; Claudepierre, S. G.; Fennell, J. F.; Reeves, G. D.; Baker, D. N.; Donovan, E.; Spanswick, E.; Kletzing, C.

2015-12-01

We present measurements from the Van Allen Probes, in the near Earth tail, at the outer boundary of the plasma sheet, of a magnetic dipolarization/injection event characterized by unusually strong earthward poynting flux flowing along magnetic field lines with amplitudes of 200 mW/m2 lasting ~ 1 minute. The Poynting flux was conjugate to a 30 km wide discrete auroral arc observed by the THEMIS auroral array. The observations were obtained at 5.8 Re in the pre-midnight sector during the main phase of a geomagnetic storm on 5/01/2013. This brief interval transferred more electromagnetic energy (at the spacecraft position) than that transferred during entire remainder of the main phase of the storm. The parallel Poynting flux coincided with a local section of the "cross tail current sheet" which generated the dipolarization signature. The latitudinal width of the arc, mapped along magnetic field lines, provides an estimate of the spatial scale of the Poynting flux, the electric fields, and the current sheets (parallel and perpendicular). It is estimated that the latitudinal width of the Poynting flux "sheet" was ~600 km or ~1-2 H+ inertial lengths. An estimate of the ∫E·dl across the current sheet along the direction normal to the plasma sheet is ~20-40 kilovolts. The "normal" to the plasma sheet component of the electric field (~70 mV/m) strongly dominated the azimuthal component(which is reponsible for drift energetization). The dipolarization event resulted in the local dispersion-less injection of electrons between 50 keV and ~2 MeV at the Van Allen Probe position. The injection event involved brief (factor of two) local spike in ~2 MeV electron fluxes. Measurements from the Los Alamos geosynchronous spacecraft, displaced eastward from the Van Allen probes, provided evidence for dispersive energy-time electron signatures consistent with injection and energization at the RBSP position. The Poynting flux also coincided with the energy peak in the up-flowing dispersive ion energy-time profile and the onset of earthward ExB convection. A similar injection event during the storm on 6/1/2013 will be discussed.

Current Highlights on ESA's Planetary Technology Reference Studies

NASA Astrophysics Data System (ADS)

Falkner, P.

The concept of Technology Reference Studies has been introduced already at EGU05, where the Venus Entry Probe (VEP), the Jupiter Minisat Explorer (JME), the Deimos Sample Return (DSR) and the Interstellar Heliopause Probe (IHP) have been presented in detail. At the EGU06 the new studies in reaction to the Cosmic Vision exercise have been introduced. The formulation of themes and mapping into potential future missions has been taken as basis in the planning of additional new and adaptation of existing TRS's to cover areas, which have not yet been addressed by any TRS. These new ongoing studies are progressing well and current highlights will be presented in the paper in further detail as well as an overview on supporting technology studies and Concurrent Design Facility (CDF) sessions. The Jupiter System Explorer (JSE) study investigates mission concepts with up to two Magnetospheric Orbiters placed in a highly elliptical Jovian orbit and the possibility to deploy a Jovian Entry Probe. The mission profile is based on a solar powered concept launched on a Soyuz-Fregat launcher. Mission analysis and the application of a new Jovian radiation model are supporting the study activities. The Near-Earth Asteroid Sample Return (NEA-SR) concept explores the possibilities of sample return or in-situ mission profiles with visits to up to two NEA targets. Due to the assumed low cost cap a trade between a sample return and remote/in-situ exploration concept has a high attention in the study. The Cross Scale TRS (CS-TRS) is intended to simultaneously investigate magnetospheric and plasma processes in three spatial scales with a formation flight of up to 12 spacecraft, orbiting on deep elliptical orbits around Earth. One of the major challenges is the launch of that number of spacecraft on a single launcher and the collisionless deployment of the formation at the target orbit. The scope if the GeoSail TRS is to demonstrate deployment, attitude control and navigation concepts for a solar sailing mission as required by Interstellar Heliopause Probe (IHP) or Solar Polar Orbiter (SPO) mission concepts and to investigate the potential influence of the extended sail for science measurements.

The OSIRIS-REx Laser Altimeter (OLA) Investigation and Instrument

NASA Astrophysics Data System (ADS)

Daly, M. G.; Barnouin, O. S.; Dickinson, C.; Seabrook, J.; Johnson, C. L.; Cunningham, G.; Haltigin, T.; Gaudreau, D.; Brunet, C.; Aslam, I.; Taylor, A.; Bierhaus, E. B.; Boynton, W.; Nolan, M.; Lauretta, D. S.

2017-10-01

The Canadian Space Agency (CSA) has contributed to the Origins Spectral Interpretation Resource Identification Security-Regolith Explorer (OSIRIS-REx) spacecraft the OSIRIS-REx Laser Altimeter (OLA). The OSIRIS-REx mission will sample asteroid 101955 Bennu, the first B-type asteroid to be visited by a spacecraft. Bennu is thought to be primitive, carbonaceous, and spectrally most closely related to CI and/or CM meteorites. As a scanning laser altimeter, the OLA instrument will measure the range between the OSIRIS-REx spacecraft and the surface of Bennu to produce digital terrain maps of unprecedented spatial scales for a planetary mission. The digital terrain maps produced will measure ˜7 cm per pixel globally, and ˜3 cm per pixel at specific sample sites. In addition, OLA data will be used to constrain and refine the spacecraft trajectories. Global maps and highly accurate spacecraft trajectory estimates are critical to infer the internal structure of the asteroid. The global and regional maps also are key to gain new insights into the surface processes acting across Bennu, which inform the selection of the OSIRIS-REx sample site. These, in turn, are essential for understanding the provenance of the regolith sample collected by the OSIRIS-REx spacecraft. The OLA data also are important for quantifying any hazards near the selected OSIRIS-REx sample site and for evaluating the range of tilts at the sampling site for comparison against the capabilities of the sample acquisition device.

Astrodynamical Space Test of Relativity using Optical Devices I (ASTROD I)—a class-M fundamental physics mission proposal for cosmic vision 2015-2025: 2010 Update

NASA Astrophysics Data System (ADS)

Braxmaier, Claus; Dittus, Hansjörg; Foulon, Bernard; Göklü, Ertan; Grimani, Catia; Guo, Jian; Herrmann, Sven; Lämmerzahl, Claus; Ni, Wei-Tou; Peters, Achim; Rievers, Benny; Samain, Étienne; Selig, Hanns; Shaul, Diana; Svehla, Drazen; Touboul, Pierre; Wang, Gang; Wu, An-Ming; Zakharov, Alexander F.

2012-10-01

ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test General Relativity with an improvement in sensitivity of over 3 orders of magnitude, improving our understanding of gravity and aiding the development of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude improvement and the anomalous Pioneer acceleration, thereby probing dark matter and dark energy gravitationally. It is envisaged as the first in a series of ASTROD missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way, two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth, to achieve the ASTROD I goals.For this mission, accurate pulse timing with an ultra-stable clock, and a drag-free spacecraft with reliable inertial sensor are required. T2L2 has demonstrated the required accurate pulse timing; rubidium clock on board Galileo has mostly demonstrated the required clock stability; the accelerometer on board GOCE has paved the way for achieving the reliable inertial sensor; the demonstration of LISA Pathfinder will provide an excellent platform for the implementation of the ASTROD I drag-free spacecraft. These European activities comprise the pillars for building up the mission and make the technologies needed ready. A second mission, ASTROD or ASTROD-GW (depending on the results of ASTROD I), is envisaged as a three-spacecraft mission which, in the case of ASTROD, would test General Relativity to one part per billion, enable detection of solar g-modes, measure the solar Lense-Thirring effect to 10 parts per million, and probe gravitational waves at frequencies below the LISA bandwidth, or in the case of ASTROD-GW, would be dedicated to probe gravitational waves at frequencies below the LISA bandwidth to 100 nHz and to detect solar g-mode oscillations. In the third phase (Super-ASTROD), larger orbits could be implemented to map the outer solar system and to probe primordial gravitational-waves at frequencies below the ASTROD bandwidth. This paper on ASTROD I is based on our 2010 proposal submitted for the ESA call for class-M mission proposals, and is a sequel and an update to our previous paper (Appouchaux et al., Exp Astron 23:491-527, 2009; designated as Paper I) which was based on our last proposal submitted for the 2007 ESA call. In this paper, we present our orbit selection with one Venus swing-by together with orbit simulation. In Paper I, our orbit choice is with two Venus swing-bys. The present choice takes shorter time (about 250 days) to reach the opposite side of the Sun. We also present a preliminary design of the optical bench, and elaborate on the solar physics goals with the radiation monitor payload. We discuss telescope size, trade-offs of drag-free sensitivities, thermal issues and present an outlook.

Gravity Probe B

NASA Image and Video Library

2003-07-11

Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment, including setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einstein’s general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Once in orbit, for 18 months each gyroscope’s spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASA’s Marshall Space Flight Center.

KSC-97PC1394

NASA Image and Video Library

1997-09-10

Dornier Satelliten Systeme (DSS) workers lift part of the Huygens probe aft cover assembly in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1388

NASA Image and Video Library

1997-09-12

Dornier Satelliten Systeme (DSS) workers lift the heat shield of the Huygens probe in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1391

NASA Image and Video Library

1997-09-12

Dornier Satelliten Systeme (DSS) workers place the back cover of the Huygens probe under its front heat shield in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1395

NASA Image and Video Library

1997-09-10

Dornier Satelliten Systeme (DSS) workers lift the front heat shield of the Huygens probe in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1390

NASA Image and Video Library

1997-09-12

Dornier Satelliten Systeme (DSS) workers place the back cover of the Huygens probe under its front heat shield in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

KSC-97PC1389

NASA Image and Video Library

1997-09-12

Dornier Satelliten Systeme (DSS) workers lift the heat shield of the Huygens probe in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after the Cassini spacecraft, aboard which Huygens will be launched, returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

Planetary Wind Determination by Doppler Tracking of a Small Entry Probe Network

NASA Astrophysics Data System (ADS)

Atkinson, D. H.; Asmar, S.; Lazio, J.; Preston, R. A.

2017-12-01

To understand the origin and chemical/dynamical evolution of planetary atmospheres, measurements of atmospheric chemistries and processes including dynamics are needed. In situ measurements of planetary winds have been demonstrated on multiple occasions, including the Pioneer multiprobe and Venera missions to Venus, and the Galileo/Jupiter and Huygens/Titan probes. However, with the exception of Pioneer Venus, the retrieval of the zonal (east-west) wind profile has been limited to a single atmospheric slice. significantly improved understanding of the global dynamics requires sampling of multiple latitudes, times of day, and seasons. Simultaneous tracking of a small network of probes would enable measurements of spatially distributed winds providing a substantially improved characterization of a planet's global atmospheric circulation. Careful selection of descent locations would provide wind measurements at latitudes receiving different solar insolations, longitudes reflecting different times of day, and different seasons if both hemispheres are targeted. Doppler wind retrievals are limited by the stability of the probe and carrier spacecraft clocks, and must be equipped with an ultrastable oscillator, accelerometers for reconstructing the probe entry trajectory, and pressure / temperature sensors for determination of descent speed. A probe were equipped with both absolute and dynamic pressure sensors can measure planet center-relative and atmosphere-relative descent speeds, enabling the measurement of vertical winds from convection or atmospheric waves. Possible ambiguities arising from the assumption of no north-south winds could be removed if the probe were simultaneously tracked from the carrier spacecraft as well as from the Earth or a second spacecraft. The global circulation of an atmosphere comprising waves and flows that vary with location and depth is inherently tied to the thermal, chemical, and energy structure of the atmosphere. Wind measurements along a single vertical atmospheric slice cannot adequately represent the overall dynamical properties of the atmosphere. To more completely characterize the dynamical structure of a planetary atmosphere, it is proposed that future in situ planetary missions include a network of small probes dedicated to wind measurements.

Mars Observer trajectory and orbit design

NASA Technical Reports Server (NTRS)

Beerer, Joseph G.; Roncoli, Ralph B.

1991-01-01

The Mars Observer launch, interplanetary, Mars orbit insertion, and mapping orbit designs are described. The design objective is to enable a near-maximum spacecraft mass to be placed in orbit about Mars. This is accomplished by keeping spacecraft propellant requirements to a minimum, selecting a minimum acceptable launch period, equalizing the spacecraft velocity change requirement at the beginning and end of the launch period, and constraining the orbit insertion maneuvers to be coplanar. The mapping orbit design objective is to provide the opportunity for global observation of the planet by the science instruments while facilitating the spacecraft design. This is realized with a sun-synchronous near-polar orbit whose ground-track pattern covers the planet at progressively finer resolution.

NASA's THEMIS Mission: Multipoint Observations of Substorms, the Foreshock, and the Magnetopause

NASA Technical Reports Server (NTRS)

Sibeck, D. G.; Angelopoulos, V.; Kuznetsova, M.; Glabmeier, K.-H.; McFadden. J. P.

2008-01-01

From launch on February 17 through the repositioning to final orbits that began in September 2007, the five-spacecraft of the THEMIS mission operated nominally in nearly identical 14.6 RE apogee near-equatorial orbits. On March 23, while aligned from east to west in the duskside magnetotail, the spacecraft observed two substorm sequences in fast survey mode. Timing the motion of these signatures served as an early proof of concept for the main phase of the mission: particle injection and dipolarization signatures propagated duskward from one probe to another, as did auroral intensifications seen by the dedicated array of ground-based observatories. During the summer of 2007, the spacecraft were on the dayside, where the three inner spacecraft (C, D, E) were separated by 100-500 km and the two outer probes (B, -4) by 5,000 - 10,000 km. Here the THEMIS probes repeatedly encountered the magnetopause and bow shock, dissecting flux transfer events (FTEs), determining the instantaneous width of the low-latitude boundary layer, and simultaneously observing hot flow anomalies upstream and downstream from the bow shock at the moment of their inception. From January to March 2008, the spacecraft were in the Earths magnetotail with apogees of 31.0, 19.5, 11.8 (2) and 10.0 RE corresponding to periods of 4, 2, and 1 days. Radial alignments once each four days offered an opportunity to pinpoint when and where substorms begin. This talk reviews THEMIS discoveries to date, with an emphasis on model-data comparisons of FTE characteristics

The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 1; The Study for the Distance 4.5Rs

NASA Technical Reports Server (NTRS)

Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

2010-01-01

Our report devotes a 3D numerical hybrid model of the interaction of the solar wind with the Solar Probe spacecraft. The SPP model includes 3 main parts, namely, a non-conducting heat shield, a support system, and cylindrical section or spacecraft bus that contains the particle analysis devices and antenna. One observes an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of about (0.06-0.6) V/m. The compression waves and the jumps in an electric field with an amplitude of about (0.15-0.7) V/m were also observed. The wave amplitudes are comparable to or greater than previously estimated max wave amplitudes that SPP is expected to measure. The results of our hybrid simulation will be useful for understanding the plasma environment near the SPP spacecraft at the distance 4.5 Rs. Future simulation will take into account the charging of the spacecraft, the charge separation effects, an outgassing from heat shield, a photoionization and an electron impact ionization effects near the spacecraft.

KSC-03PD-2738

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment. Mechanical and electrical ground support equipment will be set up and necessary connections made with the spacecraft. Spacecraft battery conditioning will also begin. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

DNA Probe Pooling for Rapid Delineation of Chromosomal Breakpoints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Chun-Mei; Kwan, Johnson; Baumgartner, Adolf

2009-01-30

Structural chromosome aberrations are hallmarks of many human genetic diseases. The precise mapping of translocation breakpoints in tumors is important for identification of genes with altered levels of expression, prediction of tumor progression, therapy response, or length of disease-free survival as well as the preparation of probes for detection of tumor cells in peripheral blood. Similarly, in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for carriers of balanced, reciprocal translocations benefit from accurate breakpoint maps in the preparation of patient-specific DNA probes followed by a selection of normal or balanced oocytes or embryos. We expedited the process of breakpointmore » mapping and preparation of case-specific probes by utilizing physically mapped bacterial artificial chromosome (BAC) clones. Historically, breakpoint mapping is based on the definition of the smallest interval between proximal and distal probes. Thus, many of the DNA probes prepared for multi-clone and multi-color mapping experiments do not generate additional information. Our pooling protocol described here with examples from thyroid cancer research and PGD accelerates the delineation of translocation breakpoints without sacrificing resolution. The turnaround time from clone selection to mapping results using tumor or IVF patient samples can be as short as three to four days.« less

Digital image transformation and rectification of spacecraft and radar images

NASA Technical Reports Server (NTRS)

Wu, S. S. C.

1985-01-01

The application of digital processing techniques to spacecraft television pictures and radar images is discussed. The use of digital rectification to produce contour maps from spacecraft pictures is described; images with azimuth and elevation angles are converted into point-perspective frame pictures. The digital correction of the slant angle of radar images to ground scale is examined. The development of orthophoto and stereoscopic shaded relief maps from digital terrain and digital image data is analyzed. Digital image transformations and rectifications are utilized on Viking Orbiter and Lander pictures of Mars.

Heat capacity mapping radiometer for AEM spacecraft

NASA Technical Reports Server (NTRS)

Sonnek, G. E.

1977-01-01

The operation, maintenance, and integration of the applications explorer mission heat capacity mapping radiometer is illustrated in block diagrams and detail schematics of circuit functions. Data format and logic timing diagrams are included along with radiometric and electronic calibration data. Mechanical and electrical configuration is presented to provide interface details for integration of the HCMR instrument to AEM spacecraft.

Gravity Recovery and Interior Laboratory (GRAIL) Mission: Status at the Initiation of the Science Mapping Phase

NASA Technical Reports Server (NTRS)

Zuber, Maria T.; Smith, David E.; Asmar, Sami W.; Alomon; Konopliv, Alexander S.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips. Roger J.; Solomon, Sean C.;

Compositional mapping of Saturn's E-ring during Cassini's flyby of Rhea

NASA Astrophysics Data System (ADS)

Khawaja, Nozair; Postberg, Frank; Srama, Ralf; Moragas-Klostermeyer, Georg; Kempf, Sascha

2015-04-01

The Cassini spacecraft was launched in 2004 towards the Saturnian system to address major scientific questions about the planet, its magnetosphere, rings and icy moons. We have performed compositional mapping of Saturn's E-ring during the Cassini's flyby (R4) of Rhea, the second largest moon of Saturn, on 9th March 2013. The icy or rocky dust particles from the surface of moons without atmosphere are ejected from their surfaces by meteoroid bombardment. The ejected particles from the moon's surface can be detected during a spacecraft flyby. In our campaign we try to identify the footprints of Rhea's surface in the composition of E ring using Cosmic Dust Analyzer (CDA) during the closest approach of Cassini's Rhea flyby. The flyby speed was 9.3km/s and the closest approach was at 997km from Rhea's surface. The Cosmic Dust Analyzer (CDA), onboard Cassini spacecraft, characterizes the micron and sub-micron dust particles at Saturn [1]. One of the tasks of CDA is to determine the chemical composition of icy and mineral dust particles at Saturn. A Time of Flight (TOF) mass spectrometer within the CDA generates mass spectra of positive ions (cations) of impinging dust particles onto the rhodium (Rh) target plate. We sampled dust grains during the entire flyby and divided the flyby into three intervals: (A) ~ -32 minutes before entering Rhea's hill sphere (B) ~ ±15 minutes from the closest approach within Rhea's hill sphere and (C) ~ +28 minutes after leaving Rhea's hill sphere. A Boxcar Analysis (BCA) is performed for compositional mapping of E-ring along the spacecraft trajectory [4]. Most of the TOF mass spectra are identified as one of the three compositional types: (i) almost pure water (ii) organic rich and (iii) salt rich [2][3]. Although we could not identify compositional information from Rhea, we have a compositional profile of the E ring. The CDA will carryout very similar measurements during Dione flyby in 2015. References [1] Srama, R. et.al.: The Cassini Cosmic Dust Analyzer, SSR, Vol. 114, 465 -- 518, 2004. [2] Postberg, F. et.al.: The E-ring in the vicinity of Enceladus II. Probing the moon's interior -- The composition of E-ring particles, Icarus, Vol. 193, 438 -- 454, 2008. [3] Postberg, F. et.al.: Sodium salts in E-ring ice grains from an ocean below the surface of Enceladus, Nature, Vol. 459, 1098 - 1101, 2009. [4] Khawaja, N. et.al.: Compositional differentiation of Enceladus' plume, EPSC, Vol. 9, 2014.

Monitoring of the Spacecraft Potential in the Magetosphere With a Double Probe Instrument

NASA Astrophysics Data System (ADS)

Laakso, H.

1998-11-01

Measurements of the double probe instrument can be used for monitoring the variation of the spacecraft potential Vs in tenuous plasmas where the satellite usually floats at a positive potential. This study deals with the Vs variation of the Polar satellite in the magnetosphere, using three and half years of data in 1996-99. The observations are binned with the Kp index in order to investigate how the level of geomagnetic activity affects the average surface potential. Two different antenna baselines are used, 6 and 60 meters, which both can be used for monitoring the spacecraft potential. In a low-density environment, however, the short antenna measurements are more influenced by the charging sheath of the satellite, but the data are nevertheless qualitatively useful. In burst mode the sampling rate of the double probe experiment is 1-8 kHz, and then very fast spacecraft potential variations can be monitored. Typically Vs varies between 0 and 50 volts so that in the plasmasphere it is 0-1 volt, at the plasmapause it exhibits a steep increase by 3-5 volts, and outside the plasmasphere Vs is more than 5 volts. Highest Vs's occur in the high-altitude (> 4 RE) polar cap, where Vs is usually between 20 and 30 volts, and on auroral field lines where it frequently lies in the 30-50 volts range and occasionally above 50 volts.

Fast E-sail Uranus entry probe mission

NASA Astrophysics Data System (ADS)

Janhunen, Pekka; Lebreton, Jean-Pierre; Merikallio, Sini; Paton, Mark; Mengali, Giovanni; Quarta, Alessandro A.

2014-12-01

The electric solar wind sail is a novel propellantless space propulsion concept. According to numerical estimates, the electric solar wind sail can produce a large total impulse per propulsion system mass. Here we consider using a 0.5 N electric solar wind sail for boosting a 550 kg spacecraft to Uranus in less than 6 years. The spacecraft is a stack consisting of the electric solar wind sail module which is jettisoned roughly at Saturn distance, a carrier module and a probe for Uranus atmospheric entry. The carrier module has a chemical propulsion ability for orbital corrections and it uses its antenna for picking up the probe's data transmission and later relaying it to Earth. The scientific output of the mission is similar to what the Galileo Probe did at Jupiter. Measurements of the chemical and isotope composition of the Uranian atmosphere can give key constraints to different formation theories of the Solar System. A similar method could also be applied to other giant planets and Titan by using a fleet of more or less identical probes.

The Interstellar Heliopause Probe/Heliospheric Explorer: IHP/HEX

NASA Astrophysics Data System (ADS)

Wimmer-Schweingruber, Robert F.; McNutt, Ralph L.

2010-03-01

The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. Dedicated deep-space missions have greatly enhanced our understanding of our immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO has allowed us to better understand the influence of the Sun and to image the glow of interstellar matter in the heliosphere. Both Voyager spacecraft have recently encountered the innermost boundary of this plasma bubble, the termination shock, and are returning exciting yet puzzling data of this remote region. The next logical step is to leave the heliosphere and to thereby map out in unprecedented detail the structure of the outer heliosphere and its boundaries, the termination shock, the heliosheath, the heliopause, and, after leaving the heliosphere, to discover the true nature of the hydrogen wall, the bow shock, and the local interstellar medium beyond. This will greatly advance our understanding of the heliosphere that is the best-known example for astrospheres as found around other stars. Thus, IHP/HEX will allow us to discover, explore, and understand fundamental astrophysical processes in the largest accessible plasma laboratory, the heliosphere.

Characterizing the performance of eddy current probes using photoinductive field-mapping

NASA Astrophysics Data System (ADS)

Moulder, John C.; Nakagawa, Norio

1992-12-01

We present a new method for characterizing the performance of eddy current probes by mapping their electromagnetic fields. The technique is based on the photoinductive effect, the change in the impedance of an eddy current probe induced by laser heating of the material under the probe. The instrument we developed maps a probe's electric field distribution by scanning an infrared laser beam over a thin film of gold lying underneath the probe. Measurements of both photoinductive signals and flaw signals for a series of similar probes demonstrates that the impedance change caused by an electrical-discharge-machined notch or a fatigue crack is proportional to the strength of the photoinductive signal. Thus, photoinductive measurements can supplant the use of artifact standards to calibrate eddy current probes.

Lunar heat flow experiments: Science objectives and a strategy for minimizing the effects of lander-induced perturbations

NASA Astrophysics Data System (ADS)

Kiefer, Walter S.

2012-01-01

Reliable measurements of the Moon's global heat flow would serve as an important diagnostic test for models of lunar thermal evolution and would also help to constrain the Moon's bulk abundance of radioactive elements and its differentiation history. The two existing measurements of lunar heat flow are unlikely to be representative of the global heat flow. For these reasons, obtaining additional heat flow measurements has been recognized as a high priority lunar science objective. In making such measurements, it is essential that the design and deployment of the heat flow probe and of the parent spacecraft do not inadvertently modify the near-surface thermal structure of the lunar regolith and thus perturb the measured heat flow. One type of spacecraft-related perturbation is the shadow cast by the spacecraft and by thermal blankets on some instruments. The thermal effects of these shadows propagate by conduction both downward and outward from the spacecraft into the lunar regolith. Shadows cast by the spacecraft superstructure move over the surface with time and only perturb the regolith temperature in the upper 0.8 m. Permanent shadows, such as from thermal blankets covering a seismometer or other instruments, can modify the temperature to greater depth. Finite element simulations using measured values of the thermal diffusivity of lunar regolith show that the limiting factor for temperature perturbations is the need to measure the annual thermal wave for 2 or more years to measure the thermal diffusivity. The error induced by permanent spacecraft thermal shadows can be kept below 8% of the annual wave amplitude at 1 m depth if the heat flow probe is deployed at least 2.5 m away from any permanent spacecraft shadow. Deploying the heat flow probe 2 m from permanent shadows permits measuring the annual thermal wave for only one year and should be considered the science floor for a heat flow experiment on the Moon. One way to meet this separation requirement would be to deploy the heat flow and seismology experiments on opposite sides of the spacecraft. This result should be incorporated in the design of future lunar geophysics spacecraft experiments. Differences in the thermal environments of the Moon and Mars result in less restrictive separation requirements for heat flow experiments on Mars.

Reacting to nuclear power systems in space: American public protests over outer planetary probes since the 1980s

NASA Astrophysics Data System (ADS)

Launius, Roger D.

2014-03-01

The United States has pioneered the use of nuclear power systems for outer planetary space probes since the 1970s. These systems have enabled the Viking landings to reach the surface of Mars and both Pioneers 10 and 11 and Voyagers 1 and 2 to travel to the limits of the solar system. Although the American public has long been concerned about safety of these systems, in the 1980s a reaction to nuclear accidents - especially the Soviet Cosmos 954 spacecraft destruction and the Three Mile Island nuclear power plant accidents - heightened awareness about the hazards of nuclear power and every spacecraft launch since that time has been contested by opponents of nuclear energy. This has led to a debate over the appropriateness of the use of nuclear power systems for spacecraft. It has also refocused attention on the need for strict systems of control and rigorous checks and balances to assure safety. This essay describes the history of space radioisotope power systems, the struggles to ensure safe operations, and the political confrontation over whether or not to allow the launch the Galileo and Cassini space probes to the outer planets. Effectively, these efforts have led to the successful flights of 12 deep space planetary probes, two-thirds of them operated since the accidents of Cosmos 954, Three Mile Island, and Chernobyl.

The Use of Langmuir Probes in Non-Maxwellian Space Plasmas

NASA Technical Reports Server (NTRS)

Hoegy, Walter R.; Brace, Larry H.

1998-01-01

Disturbance of the Maxwellian plasma may occur in the vicinity of a spacecraft due to photoemission, interactions between the spacecraft and thermospheric gases, or electron emissions from other devices on the spacecraft. Significant non-maxwellian plasma distributions may also occur in nature as a mixture of ionospheric and magnetospheric plasmas or secondaries produced by photoionization in the thermosphere or auroral precipitation. The general formulas for current collection (volt-ampere curves) by planar, cylindrical, and spherical Langmuir probes in isotropic and anisotropic non-maxwellian plasmas are examined. Examples are given of how one may identify and remove the non-maxwellian components in the Langmuir probe current to permit the ionospheric parameters to be determined. Theoretical volt-ampere curves presented for typical examples of non-maxwellian distributions include: two-temperature plasmas and a thermal plasma with an energetic electron beam. If the non-ionospheric electrons are Maxwellian at a temperature distinct from that of the ionosphere electrons, the volt-ampere curves can be fitted directly to obtain the temperatures and densities of both electron components without resorting to differenting the current. For an arbitrary isotropic distribution, the current for retarded particles is shown to be identical for the three geometries. For anisotropic distributions, the three probe geometries are not equally suited for measuring the ionospheric electron temperature and density or for determining the distribution function in the presence of non-maxwellian back-round electrons.

Near-Infrared Spectroscopy and Spectral Mapping of Jupiter and the Galilean Satellites: Results from Galileo's Initial Orbit

NASA Technical Reports Server (NTRS)

Carlson, R.; Smythe, W.; Baines, K.; Barbinis, E.; Becker, K.; Burns, R.; Calcutt, S.; Calvin, W.; Clark, R.; Danielson, G.;

IBEX: The Evolving Global View and Synergies with In Situ Voyager Observations

NASA Astrophysics Data System (ADS)

McComas, D. J.

2015-12-01

The Interstellar Boundary Explorer (IBEX) has now returned nearly seven years of observations, which comprise 14 full sets of energy resolved all-sky maps and provide the global view of our Sun's interaction with very local part of the galaxy. With such a long baseline of observations, we are able to examine time variations in the outer heliosphere as it responds to both 11-year solar cycle variations and longer term secular evolution of the three dimensional solar wind. Now that we have collected over half a solar cycle of observations, IBEX is beginning to show us how the heliosphere - our home in the galaxy - varies in time as well as space. In this talk we present the most recent observations and review some other recent discoveries from IBEX. We also examine the synergy between the global view provided by IBEX and the in situ observations form the Voyager 1 and 2 spacecraft. Finally, we discuss the incredible improvement in interstellar observations - and our understanding of the local interstellar medium - that the Interstellar Mapping and Acceleration Probe (IMAP) will provide.

Gravity Probe B

NASA Image and Video Library

2003-07-13

In the spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to remove the soft shipping cover from the Gravity Probe B experiment. Immediate processing includes setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einstein’s general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Once in orbit, for 18 months each gyroscope’s spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASA’s Marshall Space Flight Center.

SMART-1 SPEDE: Results and Legacy after 10 Years

NASA Astrophysics Data System (ADS)

Schmidt, Walter; Mälkki, Anssi

2014-05-01

The Spacecraft Potential, Electron and Dust Experiment (SPEDE) [1], one of the instruments on the SMART-1 spacecraft, the European Space Agency's first Lunar mission, was part of the monitoring instruments supervising the propulsion system and supporting corrective actions to its operation when needed. During mission phases with inactive propulsion system the plasma instrument measured electron and ion densities and temperatures of the natural plasma in the vicinity of the spacecraft. While the spacecraft was slowly spiraling out of an Earth orbit towards a Moon trajectory it spent many months inside the Earth radiation belt. During this time SPEDE recorded the plasma parameters as a function of altitude and solar conditions and monitored also the effects of the major solar CME of October 28, the so-called "Halloween Storm" [2], [3]. After reaching the Moon on November 15, 2004, it continued to monitor the plasma and dust impacts onto the spacecraft until the end of the mission on September 3, 2006. Most of the Moon orbits lasted about 5 hours with an initial perilune distance of 2208 and an apolune distance of 4618 km, changing to 300 km and 3000km, respectively towards the end of the mission with a controlled impact onto the Lunar surface. A total of over 200 orbits were covered [4]. Covered by the SPEDE instrument are three areas of scientific interest: - A detailed altitude profile of the plasma parameters inside the radiation belt under different environmental condition - SPEDE was one of the few instruments active inside the radiation belt while normally all instruments on space missions are kept off to prevent damage, - a plasma parameter map in Lunar orbit with the Moon inside and outside the Earth magnetosphere, - plasma wave measurements around the moon with signatures of dust impacts onto the spacecraft monitoring the dust lifting processes on the Moon surface to escape velocities under certain solar wind conditions. Technical legacy: The Langmuir Probe sensor area treatment was optimized for SPEDE and used in all subsequent Langmuir probe designs of IRF/Uppsala. The algorithm implemented inside the SPEDE on-board software to analyze the plasma wave measurements was optimized during the SMART-1 mission and later uplinked to the ESA Rosetta spacecraft lander Philae, where it is now used to analyze and compress the data of the permittivity probe, also used as a plasma wave monitor with W.Schmidt as PI. The experience gained from the FPGA-implementation of a self-developed processor was later used in preparation of ESA's ExoMars 2016 pressure sensor controller and the Swedish plasma instrument LINA for a Russian Lunar mission as well as for the ESA JUICE mission to the Jupiter system. Reference: [1] Mälkki, A., Schmidt, W., Laakso, H., Grard, R., Escoubet, C.P., Wahlund, J.-E., Blomberg, L., Marklund, G. and Johlander, B., 2003: The SPEDE experiment on SMART-1: Instrument, mission, and science objectives. Geophysical Research Abstracts, Vol 5., 10004, 2003. [2] Mälkki, A., Schmidt, W., Laakso, H., Johlander, B., Wahlund, J.E., Blomberg, L., Marklund, G., Grard, R., Escoubet, C.P. and Lebreton, J.P., 2004: First results from SMART-1/ SPEDE plasma experiment. European Geophysical Union EGU-2004, EGU04-A-02543. Invited oral presentation [3] Mälkki, A., Schmidt, W., Genzer, M., Merikallio, S., Laakso, H., Gonzales del Amo, J., Estublier, D., Gengembre, E., Hilgers, A., Capacci, M., Koppel, C. and Tajmar, M., 2005: Spacecraft-plasma interaction analysis using data from SPEDE on SMART-1. 10th Scientific Assembly of IAGA, Toulouse, France, July 2005, paper IAGA2005-A-01401 [4] Mälkki, A., Schmidt, W., Kallio, E. and Merikallio, S., 2006: Interaction of Solar Wind With the Moon: Results From Hybrid Modeling and the SPEDE Instrument on SMART-1. Geophysical Research Abstracts, Vol. 8, 07632, 2006 [5] M.Backrud, 2007: Evaluation of the SPEDE instrument on SMART-1, Royal Institute of Technology (KTH) Report - TRITA-EE 2007:023

Deep Impact Spacecraft Collides With Comet Tempel 1 (Video)

NASA Technical Reports Server (NTRS)

2005-01-01

After 172 days and 268 million miles of deep space travel, the NASA Deep Impact spacecraft successfully reached out and touched comet Tempel 1. The collision between the coffee table-sized space probe and city-sized comet occurred July 4, 2005 at 12:52 a.m. CDT. Comprised of images taken by the targeting sensor aboard the impactor probe, this movie shows the spacecraft approaching the comet up to just seconds before impact. Mission scientists expect Deep Impact to provide answers to basic questions about the formation of the solar system. Principal investigator for Deep Impact, Dr. Michael A'Hearn of the University of Maryland in College Park, is responsible for the mission, and project management is handled by the Jet Propulsion Laboratory in Pasadena, California. The program office at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama assisted the Science Mission Directorate at NASA Headquarters in Washington with program management, technology planning, systems assessment, flight assurance and public outreach. The spacecraft was built for NASA by Ball Aerospace & Technologies Corporation of Boulder, Colorado. (NASA/JPL-Caltech/UMD)

EMIC Wave Scale Size in the Inner Magnetosphere: Observations From the Dual Van Allen Probes

NASA Technical Reports Server (NTRS)

Blum, L. W.; Bonnell, J. W.; Agapitov, O.; Paulson, K.; Kletzing, C.

2017-01-01

Estimating the spatial scales of electromagnetic ion cyclotron (EMIC) waves is critical for quantifying their overall scattering efficiency and effects on thermal plasma, ring current, and radiation belt particles. Using measurements from the dual Van Allen Probes in 2013-2014, we characterize the spatial and temporal extents of regions of EMIC wave activity and how these depend on local time and radial distance within the inner magnetosphere. Observations are categorized into three types: waves observed by only one spacecraft, waves measured by both spacecraft simultaneously, and waves observed by both spacecraft with some time lag. Analysis reveals that dayside (and H+ band) EMIC waves more frequently span larger spatial areas, while nightside (and He+ band) waves are more often localized but can persist many hours. These investigations give insight into the nature of EMIC wave generation and support more accurate quantification of their effects on the ring current and outer radiation belt.

EMIC wave scale size in the inner magnetosphere: Observations from the dual Van Allen Probes

NASA Astrophysics Data System (ADS)

Blum, L. W.; Bonnell, J. W.; Agapitov, O.; Paulson, K.; Kletzing, C.

2017-02-01

Estimating the spatial scales of electromagnetic ion cyclotron (EMIC) waves is critical for quantifying their overall scattering efficiency and effects on thermal plasma, ring current, and radiation belt particles. Using measurements from the dual Van Allen Probes in 2013-2014, we characterize the spatial and temporal extents of regions of EMIC wave activity and how these depend on local time and radial distance within the inner magnetosphere. Observations are categorized into three types—waves observed by only one spacecraft, waves measured by both spacecraft simultaneously, and waves observed by both spacecraft with some time lag. Analysis reveals that dayside (and H+ band) EMIC waves more frequently span larger spatial areas, while nightside (and He+ band) waves are more often localized but can persist many hours. These investigations give insight into the nature of EMIC wave generation and support more accurate quantification of their effects on the ring current and outer radiation belt.

Design and development of the Cassini main engine assembly Gimbal mechanism

NASA Technical Reports Server (NTRS)

Rudolph, Dale

1996-01-01

Cassini is an international cooperative effort between NASA, which is producing the orbiter spacecraft, the European Space Agency, which is providing the Huygens Probe, and the Italian Space Agency, which is responsible for the spacecraft radio antenna and portions of three scientific experiments. In the U.S., the mission is managed by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. Lockheed-Martin successfully bid on the contract to build the PMS (Propulsion Module Subsystem) for this project. The Cassini spacecraft will be launched on an expedition to Saturn in October, 1997. Its mission is to enter orbit around Saturn in July, 2004, and to explore its moons, rings, and magnetic environment for four years. Cassini will carry the Huygens probe, an instrument package equipped with a parachute, which is designed to study the atmosphere and surface of Saturn's largest moon, Titan.

Using Solar Radiation Pressure to Control L2 Orbits

NASA Technical Reports Server (NTRS)

Tene, Noam; Richon, Karen; Folta, David

1998-01-01

The main perturbations at the Sun-Earth Lagrange points L1 and L2 are from solar radiation pressure (SRP), the Moon and the planets. Traditional approaches to trajectory design for Lagrange-point orbits use maneuvers every few months to correct for these perturbations. The gravitational effects of the Moon and the planets are small and periodic. However, they cannot be neglected because small perturbations in the direction of the unstable eigenvector are enough to cause exponential growth within a few months. The main effect of a constant SRP is to shift the center of the orbit by a small distance. For spacecraft with large sun-shields like the Microwave Anisotropy Probe (MAP) and the Next Generation Space Telescope (NGST), the SRP effect is larger than all other perturbations and depends mostly on spacecraft attitude. Small variations in the spacecraft attitude are large enough to excite or control the exponential eigenvector. A closed-loop linear controller based on the SRP variations would eliminate one of the largest errors to the orbit and provide a continuous acceleration for use in controlling other disturbances. It is possible to design reference trajectories that account for the periodic lunar and planetary perturbations and still satisfy mission requirements. When such trajectories are used the acceleration required to control the unstable eigenvector is well within the capabilities of a continuous linear controller. Initial estimates show that by using attitude control it should be possible to minimize and even eliminate thruster maneuvers for station keeping.

Recent Progress on Understanding SEP Acceleration and Transport

NASA Astrophysics Data System (ADS)

Cohen, C.

2017-12-01

Joint observations between near-Earth spacecraft and the twin STEREO spacecraft have allowed new examinations of the longitudinal extent of solar energetic particles (SEPs). Although the radial dependence will not be measured in detail until Parker Solar Probe and Solar Orbiter have launched, recent developments in modeling SEP acceleration and transport have revealed interesting dependences on magnetic field configurations and the characteristics of seed particle populations. This talk will review recent SEP in-situ observations along with theoretical studies and their implications for our understanding of SEP acceleration and transport in the inner heliosphere and our expectations for upcoming Solar Orbiter and Parker Solar Probe observations.

Short Wavelength Electromagnetic Perturbations Excited Near the Solar Probe Plus Spacecraft in the Inner Heliosphere: 2.5D Hybrid Modeling

NASA Technical Reports Server (NTRS)

Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

2011-01-01

A 2.5D numerical plasma model of the interaction of the solar wind (SW) with the Solar Probe Plus spacecraft (SPPSC) is presented. These results should be interpreted as a basic plasma model derived from the SW-interaction with the spacecraft (SC), which could have consequences for both plasma wave and electron plasma measurements on board the SC in the inner heliosphere. Compression waves and electric field jumps with amplitudes of about 1.5 V/m and (12-18) V/m were also observed. A strong polarization electric field was also observed in the wing of the plasma wake. However, 2.5D hybrid modeling did not show excitation of whistler/Alfven waves in the upstream connected with the bidirectional current closure that was observed in short-time 3D modeling SPPSC and near a tether in the ionosphere. The observed strong electromagnetic perturbations may be a crucial point in the electromagnetic measurements planned for the future Solar Probe Plus (SPP) mission. The results of modeling electromagnetic field perturbations in the SW due to shot noise in absence of SPPSC are also discussed.

Spacecraft-level verification of the Van Allen Probes' RF communication system

NASA Astrophysics Data System (ADS)

Crowne, M. J.; Srinivasan, D.; Royster, D.; Weaver, G.; Matlin, D.; Mosavi, N.

This paper presents the verification process, lessons learned, and selected test results of the radio frequency (RF) communication system of the Van Allen Probes, formerly known as the Radiation Belt Storm Probes (RBSP). The Van Allen Probes mission is investigating the doughnut-shaped regions of space known as the Van Allen radiation belts where the Sun interacts with charged particles trapped in Earth's magnetic field. Understanding this dynamic area that surrounds our planet is important to improving our ability to design spacecraft and missions for reliability and astronaut safety. The Van Allen Probes mission features two nearly identical spacecraft designed, built, and operated by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) for the National Aeronautics and Space Administration (NASA). The RF communication system features the JHU/APL Frontier Radio. The Frontier Radio is a software-defined radio (SDR) designed for spaceborne communications, navigation, radio science, and sensor applications. This mission marks the first spaceflight usage of the Frontier Radio. RF ground support equipment (RF GSE) was developed using a ground station receiver similar to what will be used in flight and whose capabilities provided clarity into RF system performance that was previously not obtained until compatibility testing with the ground segments. The Van Allen Probes underwent EMC, acoustic, vibration, and thermal vacuum testing at the environmental test facilities at APL. During this time the RF communication system was rigorously tested to ensure optimal performance, including system-level testing down to threshold power levels. Compatibility tests were performed with the JHU/APL Satellite Communication Facility (SCF), the Universal Space Network (USN), and the Tracking and Data Relay Satellite System (TDRSS). Successful completion of this program as described in this paper validated the design of the system and demonstrated that it will be able to me- t all of the Van Allen Probes's communications requirements with its intended ground segments.

Status and future of extraterrestrial mapping programs

NASA Technical Reports Server (NTRS)

Batson, R. M.

1981-01-01

Extensive mapping programs have been completed for the Earth's Moon and for the planet Mercury. Mars, Venus, and the Galilean satellites of Jupiter (Io, Europa, Ganymede, and Callisto), are currently being mapped. The two Voyager spacecraft are expected to return data from which maps can be made of as many as six of the satellites of Saturn and two or more of the satellites of Uranus. The standard reconnaissance mapping scales used for the planets are 1:25,000,000 and 1:5,000,000; where resolution of data warrants, maps are compiled at the larger scales of 1:2,000,000, 1:1,000,000 and 1:250,000. Planimetric maps of a particular planet are compiled first. The first spacecraft to visit a planet is not designed to return data from which elevations can be determined. As exploration becomes more intensive, more sophisticated missions return photogrammetric and other data to permit compilation of contour maps.

Mapped DNA probes from Ioblolly pine can be used for restriction fragment length polymorphism mapping in other conifers

Treesearch

M.R. Ahuja; M.E. Devey; A.T. Groover; K.D. Jermstad; D.B Neale

1994-01-01

A high-density genetic map based on restriction fragment length polymorphisms (RFLPs) is being constructed for loblolly pine (Pinus taeda L.). Consequently, a large number of DNA probes from loblolly pine are potentially available for use in other species. We have used some of these DNA probes to detect RFLPs in 12 conifers and an angiosperm....

KSC-2012-4353

NASA Image and Video Library

2012-08-10

CAPE CANAVERAL, Fla. – The Radiation Belt Storm Probes, or RBSP, spacecraft are moved inside their payload fairing on the payload transporter from the Astrotech payload processing facility in Titusville, Fla. to Space Launch Complex-41 at Cape Canaveral Air Force Station. The fairing, which holds the twin RBSP spacecraft, will be lifted to the top of a United Launch Alliance Atlas V rocket for launch later in August. The two spacecraft are designed to study the Van Allen radiation belts in unprecedented detail. Photo credit: NASA/Dmitri Gerondidakis

Systems design study of the Pioneer Venus spacecraft. Volume 1. Technical analyses and tradeoffs, section 7 (part 3 of 4). [aerodynamic design problems for small probe reentry

NASA Technical Reports Server (NTRS)

1973-01-01

The aerodynamic design problems for the Pioneer Venus mission are discussed for a small probe shape that enters the atmosphere, and exhibits good stability for the subsonic portion of the flight. The problems discussed include: heat shield, structures and mechanisms, thermal control, decelerator, probe communication, data handling and command, and electric power.

An employee sews thermal insulation material on the front heat shield of the Huygens probe in the PH

NASA Technical Reports Server (NTRS)

1997-01-01

An employee in the Payload Hazardous Servicing Facility (PHSF) sews thermal insulation material on the front heat shield of the Huygens probe during prelaunch processing testing and integration in that facility, with the probe's back cover in the background. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.

Science Planning and Orbit Classification for Solar Probe Plus

NASA Astrophysics Data System (ADS)

Kusterer, M. B.; Fox, N. J.; Rodgers, D. J.; Turner, F. S.

2016-12-01

There are a number of challenges for the Science Planning Team (SPT) of the Solar Probe Plus (SPP) Mission. Since SPP is using a decoupled payload operations approach, tight coordination between the mission operations and payload teams will be required. The payload teams must manage the volume of data that they write to the spacecraft solid-state recorders (SSR) for their individual instruments for downlink to the ground. Making this process more difficult, the geometry of the celestial bodies and the spacecraft during some of the SPP mission orbits cause limited uplink and downlink opportunities. The payload teams will also be required to coordinate power on opportunities, command uplink opportunities, and data transfers from instrument memory to the spacecraft SSR with the operation team. The SPT also intend to coordinate observations with other spacecraft and ground based systems. To solve these challenges, detailed orbit activity planning is required in advance for each orbit. An orbit planning process is being created to facilitate the coordination of spacecraft and payload activities for each orbit. An interactive Science Planning Tool is being designed to integrate the payload data volume and priority allocations, spacecraft ephemeris, attitude, downlink and uplink schedules, spacecraft and payload activities, and other spacecraft ephemeris. It will be used during science planning to select the instrument data priorities and data volumes that satisfy the orbit data volume constraints and power on, command uplink and data transfer time periods. To aid in the initial stages of science planning we have created an orbit classification scheme based on downlink availability and significant science events. Different types of challenges arise in the management of science data driven by orbital geometry and operational constraints, and this scheme attempts to identify the patterns that emerge.

Evaluation of SNP Data from the Malus Infinium Array Identifies Challenges for Genetic Analysis of Complex Genomes of Polyploid Origin.

PubMed

Troggio, Michela; Surbanovski, Nada; Bianco, Luca; Moretto, Marco; Giongo, Lara; Banchi, Elisa; Viola, Roberto; Fernández, Felicdad Fernández; Costa, Fabrizio; Velasco, Riccardo; Cestaro, Alessandro; Sargent, Daniel James

2013-01-01

High throughput arrays for the simultaneous genotyping of thousands of single-nucleotide polymorphisms (SNPs) have made the rapid genetic characterisation of plant genomes and the development of saturated linkage maps a realistic prospect for many plant species of agronomic importance. However, the correct calling of SNP genotypes in divergent polyploid genomes using array technology can be problematic due to paralogy, and to divergence in probe sequences causing changes in probe binding efficiencies. An Illumina Infinium II whole-genome genotyping array was recently developed for the cultivated apple and used to develop a molecular linkage map for an apple rootstock progeny (M432), but a large proportion of segregating SNPs were not mapped in the progeny, due to unexpected genotype clustering patterns. To investigate the causes of this unexpected clustering we performed BLAST analysis of all probe sequences against the 'Golden Delicious' genome sequence and discovered evidence for paralogous annealing sites and probe sequence divergence for a high proportion of probes contained on the array. Following visual re-evaluation of the genotyping data generated for 8,788 SNPs for the M432 progeny using the array, we manually re-scored genotypes at 818 loci and mapped a further 797 markers to the M432 linkage map. The newly mapped markers included the majority of those that could not be mapped previously, as well as loci that were previously scored as monomorphic, but which segregated due to divergence leading to heterozygosity in probe annealing sites. An evaluation of the 8,788 probes in a diverse collection of Malus germplasm showed that more than half the probes returned genotype clustering patterns that were difficult or impossible to interpret reliably, highlighting implications for the use of the array in genome-wide association studies.

Spacecraft Interactions Studies with a 1 Kw Class Closed-Drift Hall Thruster

DTIC Science & Technology

1998-01-31

Closed Drift Hall thruster plume with spacecraft surfaces and systems. Two basic interaction modes were investigated: (1) the influence of the plume...Spectrometer (MBMS) capable of discerning both the mass and energy of Hall thruster plume species, and the ion acoustic wave probe to measure the drift velocity of the plume plasma.

Systems design study of the Pioneer Venus spacecraft. Appendices to volume 1, sections 8-11 (part 3 of 3). [power subsystem/cost tradeoffs for Venus probe

NASA Technical Reports Server (NTRS)

1973-01-01

Power subsystem cost/weight tradeoffs are discussed for the Venus probe spacecraft. The cost estimations of power subsystem units were based upon DSCS-2, DSP, and Pioneer 10 and 11 hardware design and development and manufacturing experience. Parts count and degree of modification of existing hardware were factored into the estimate of manufacturing and design and development costs. Cost data includes sufficient quantities of units to equip probe bus and orbiter versions. It was based on the orbiter complement of equipment, but the savings in fewer slices for the probe bus balance the cost of the different probe bus battery. The preferred systems for the Thor/Delta and for the Atlas/Centaur are discussed. The weights of the candidate designs were based upon slice or tray weights for functionally equivalent circuitry measured on existing hardware such as Pioneers 10 and 11, Intelsat 3, DSCS-2, or DSP programs. Battery weights were based on measured cell weight data adjusted for case weight or off-the-shelf battery weights. The solar array weight estimate was based upon recent hardware experience on DSCS-2 and DSP arrays.

Propulsion Instruments for Small Hall Thruster Integration

NASA Technical Reports Server (NTRS)

Johnson, Lee K.; Conroy, David G.; Spanjers, Greg G.; Bromaghim, Daron R.

2001-01-01

Planning and development are underway for the propulsion instrumentation necessary for the next AFRL electric propulsion flight project, which includes both a small Hall thruster and a micro-PPT. These instruments characterize the environment induced by the thruster and the associated data constitute part of a 'user's manual' for these thrusters. Several instruments probe the back-flow region of the thruster plume, and the data are intended for comparison with detailed numerical models in this region. Specifically, an ion probe is under development to determine the energy and species distributions, and a Langmuir probe will be employed to characterize the electron density and temperature. Other instruments directly measure the effects of thruster operation on spacecraft thermal control surfaces, optical surfaces, and solar arrays. Specifically, radiometric, photometric, and solar-cell-based sensors are under development. Prototype test data for most sensors should be available, together with details of the instrumentation subsystem and spacecraft interface.

Cost-Effective NEO Characterization Using Solar Electric Propulsion (SEP)

NASA Astrophysics Data System (ADS)

Dissly, R. W.; Reinert, R.; Mitchell, S.

2003-05-01

We present a cost-effective multiple NEO rendezvous mission design optimized around the capabilities of Ball's 200-kg NEOX Solar Electric Propelled microsatellite. The NEOX spacecraft is 3-axis stabilized with better-than 1 milliradian pointing accuracy to serve as an excellent imaging platform; its DSN compatible telecommunications subsystem can support a 6.4-kbps downlink rate at 3 AU earth range. The spacecraft mass is <200kg at launch to allow launch as a cost-effective secondary payload. It uses proven SEP technology to provide 12km/s of Delta-V, which enables multiple rendezvous' in a single mission. Cost-effectiveness is optimized by launch as a secondary payload (e.g., Ariane-5 ASAP) or as a multiple manifest on a single dedicated launch vehicle (e.g., 4 on a Delta-II 2925). Following separation from the LV, we describe a candidate mission profile that minimizes cost by using the spacecraft's 12km/s of SEP Delta-V to allow orbiting up to 4 separate NEO's. Orbiting as opposed to flying by augments the mission's science return by providing the NEO mass and by allowing multiple phase angle imaging. The NEOX Spacecraft has the capability to support a 20kg payload drawing 100W average during SEP cruise, with >1kW available during the NEO orbital phase when the SEP thrusters are not powered. We will present a candidate payload suite that includes a visible/NIR imager, a laser altimeter, and a set of small, self-righting surface probes that can be used to assess the geophysical state of the object surface and near-surface environments. The surface probe payload notionally includes a set of cameras for imaging the body surface at mm-scale resolution, an accelerometer package to measure surface mechanical properties upon probe impact, a Langmuir probe to measure the electrostatic gradient immediately above the object surface, and an explosive charge that can be remotely detonated at the end of the surface mission to excavate an artificial crater that can be remotely observed from the orbiting spacecraft.

The Interstellar Ethics of Self-Replicating Probes

NASA Astrophysics Data System (ADS)

Cooper, K.

Robotic spacecraft have been our primary means of exploring the Universe for over 50 years. Should interstellar travel become reality it seems unlikely that humankind will stop using robotic probes. These probes will be able to replicate themselves ad infinitum by extracting raw materials from the space resources around them and reconfiguring them into replicas of themselves, using technology such as 3D printing. This will create a colonising wave of probes across the Galaxy. However, such probes could have negative as well as positive consequences and it is incumbent upon us to factor self-replicating probes into our interstellar philosophies and to take responsibility for their actions.

Orbit Determination and Navigation of the Time History of Events and Macroscale Interactions during Substorms (THEMIS)

NASA Technical Reports Server (NTRS)

Morinelli, Patrick; Cosgrove, Jennifer; Blizzard, Mike; Robertson, Mike

2007-01-01

This paper provides an overview of the launch and early orbit activities performed by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of five probes comprising the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft. The FDF was tasked to support THEMIS in a limited capacity providing backup orbit determination support for validation purposes for all five THEMIS probes during launch plus 30 days in coordination with University of California Berkeley Flight Dynamics Center (UCB/FDC)2. The FDF's orbit determination responsibilities were originally planned to be as a backup to the UCB/FDC for validation purposes only. However, various challenges early on in the mission and a Spacecraft Emergency declared thirty hours after launch placed the FDF team in the role of providing the orbit solutions that enabled contact with each of the probes and the eventual termination of the Spacecraft Emergency. This paper details the challenges and various techniques used by the GSFC FDF team to successfully perform orbit determination for all five THEMIS probes during the early mission. In addition, actual THEMIS orbit determination results are presented spanning the launch and early orbit mission phase. Lastly, this paper enumerates lessons learned from the THEMIS mission, as well as demonstrates the broad range of resources and capabilities within the FDF for supporting critical launch and early orbit navigation activities, especially challenging for constellation missions.

Orbit Determination and Navigation of the Time History of Events and Macroscale Interactions during Substorms (THEMIS)

NASA Technical Reports Server (NTRS)

Morinelli, Patrick; Cosgrove, jennifer; Blizzard, Mike; Nicholson, Ann; Robertson, Mika

2007-01-01

This paper provides an overview of the launch and early orbit activities performed by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of five probes comprising the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft. The FDF was tasked to support THEMIS in a limited capacity providing backup orbit determination support for validation purposes for all five THEMIS probes during launch plus 30 days in coordination with University of California Berkeley Flight Dynamics Center (UCB/FDC). The FDF's orbit determination responsibilities were originally planned to be as a backup to the UCB/FDC for validation purposes only. However, various challenges early on in the mission and a Spacecraft Emergency declared thirty hours after launch placed the FDF team in the role of providing the orbit solutions that enabled contact with each of the probes and the eventual termination of the Spacecraft Emergency. This paper details the challenges and various techniques used by the GSFC FDF team to successfully perform orbit determination for all five THEMIS probes during the early mission. In addition, actual THEMIS orbit determination results are presented spanning the launch and early orbit mission phase. Lastly, this paper enumerates lessons learned from the THEMIS mission, as well as demonstrates the broad range of resources and capabilities within the FDF for supporting critical launch and early orbit navigation activities, especially challenging for constellation missions.

The Oxford Probe: an open access five-hole probe for aerodynamic measurements

NASA Astrophysics Data System (ADS)

Hall, B. F.; Povey, T.

2017-03-01

The Oxford Probe is an open access five-hole probe designed for experimental aerodynamic measurements. The open access probe can be manufactured by the end user via additive manufacturing (metal or plastic). The probe geometry, drawings, calibration maps, and software are available under a creative commons license. The purpose is to widen access to aerodynamic measurement techniques in education and research environments. There are many situations in which the open access probe will allow results of comparable accuracy to a well-calibrated commercial probe. We discuss the applications and limitations of the probe, and compare the calibration maps for 16 probes manufactured in different materials and at different scales, but with the same geometrical design.

Ground correlation investigation of thruster spacecraft interactions to be measured on the IAPS flight test

NASA Technical Reports Server (NTRS)

Power, J. L.

1984-01-01

Preliminary ground correlation testing has been conducted with an 8 cm mercury ion thruster and diagnostic instrumentation replicating to a large extent the IAPS flight test hardware, configuration, and electrical grounding/isolation. Thruster efflux deposition retained at 25 C was measured and characterized. Thruster ion efflux was characterized with retarding potential analyzers. Thruster-generated plasma currents, the spacecraft common (SCC) potential, and ambient plasma properties were evaluated with a spacecraft potential probe (SPP). All the measured thruster/spacecraft interactions or their IAPS measurements depend critically on the SCC potential, which can be controlled by a neutralizer ground switch and by the SPP operation.

Galileo spacecraft power distribution and autonomous fault recovery

NASA Technical Reports Server (NTRS)

Detwiler, R. C.

1982-01-01

There is a trend in current spacecraft design to achieve greater fault tolerance through the implemenation of on-board software dedicated to detecting and isolating failures. A combination of hardware and software is utilized in the Galileo power system for autonomous fault recovery. Galileo is a dual-spun spacecraft designed to carry a number of scientific instruments into a series of orbits around the planet Jupiter. In addition to its self-contained scientific payload, it will also carry a probe system which will be separated from the spacecraft some 150 days prior to Jupiter encounter. The Galileo spacecraft is scheduled to be launched in 1985. Attention is given to the power system, the fault protection requirements, and the power fault recovery implementation.

KSC-03PD-2742

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Enclosed in a canister, the Gravity Probe B (GP-B) spacecraft arrives on Vandenberg Air Force Base, headed for the spacecraft processing facility. Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

KSC-03PD-2743

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Enclosed in a canister, the Gravity Probe B (GP-B) spacecraft arrives at the spacecraft processing facility on North Vandenberg Air Force Base . Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

Molecular mapping of chromosomes 17 and X

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barker, D.F.

1991-01-15

Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved characterization of the relative locations of the breakpoints with respect to each other and the definition ofmore » new physical intervals. The strategy for isolation of the polymorphic clones utilized chromosome specific libraries of 1--15 kb segments from each of the two chromosomes. From these libraries, clones were screened for those detecting restriction fragment length polymorphisms. The markers were further characterized, the chromosomal assignments confirmed and in most cases segments of the original probes were subcloned into plasmids to produce probes with improved signal to noise ratios for use in the genetic marker studies. The linkage studies utilize the CEPH reference families and other well-characterized families in our collection which have been used for genetic disease linkage work. Preliminary maps and maps of portions of specific regions of 17 and X are provided. We have nearly completed a map of the 1 megabase Mycoplasma arthritidis genome by applying these techniques to a lambda phage library of its genome. We have found bit mapping to be an efficient means to organize a contiguous set of overlapping clones from a larger genome.« less

Molecular mapping of chromosomes 17 and X. Progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barker, D.F.

1991-01-15

Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved characterization of the relative locations of the breakpoints with respect to each other and the definition ofmore » new physical intervals. The strategy for isolation of the polymorphic clones utilized chromosome specific libraries of 1--15 kb segments from each of the two chromosomes. From these libraries, clones were screened for those detecting restriction fragment length polymorphisms. The markers were further characterized, the chromosomal assignments confirmed and in most cases segments of the original probes were subcloned into plasmids to produce probes with improved signal to noise ratios for use in the genetic marker studies. The linkage studies utilize the CEPH reference families and other well-characterized families in our collection which have been used for genetic disease linkage work. Preliminary maps and maps of portions of specific regions of 17 and X are provided. We have nearly completed a map of the 1 megabase Mycoplasma arthritidis genome by applying these techniques to a lambda phage library of its genome. We have found bit mapping to be an efficient means to organize a contiguous set of overlapping@ clones from a larger genome.« less

Mercator Projection of Huygens View

NASA Image and Video Library

2006-05-04

This poster shows a flattened (Mercator) projection of the Huygens probe's view from 10 kilometers altitude (6 miles). The images that make up this view were taken on Jan. 14, 2005, with the descent imager/spectral radiometer onboard the European Space Agency's Huygens probe. The Huygens probe was delivered to Saturn's moon Titan by the Cassini spacecraft, which is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif. NASA supplied two instruments on the probe, the descent imager/spectral radiometer and the gas chromatograph mass spectrometer. http://photojournal.jpl.nasa.gov/catalog/PIA08113

The Voyager flights to Jupiter and Saturn

NASA Technical Reports Server (NTRS)

1982-01-01

The results of the mini-Grand Tour to Jupiter and Saturn by the Voyager 1 and 2 spacecraft are highlighted. Features of the spacecraft are depicted including the 11 instruments designed to probe the planets and their magnetic environments, the rings of Saturn, the fleets of satellites escorting the planets, and the interplanetary medium. Major scientific discoveries relating to these phenomena are summarized.

Looking Back at a Job Well Done

NASA Technical Reports Server (NTRS)

2005-01-01

This image shows the view from Deep Impact's flyby spacecraft as it turned back to look at comet Tempel 1. Fifty minutes earlier, the spacecraft's probe was run over by the comet. That collision kicked up plumes of ejected material, seen here streaming away from the back side of the comet. This image was taken by the flyby craft's high-resolution camera.

Telecommunications and data acquisition support for the Pioneer Venus Project: Pioneers 12 and 13, prelaunch through March 1984

NASA Technical Reports Server (NTRS)

Miller, R. B.; Ryan, R. E.; Renzetti, N. A.; Traxler, M. R.

1984-01-01

The support provided by the Telecommunications and Data Acquisition organization of the Jet Propulsion Laboratory (JPL) to the Pioneer Venus missions is described. The missions were the responsibility of the Ames Research Center (ARC). The Pioneer 13 mission and its spacecraft design presented one of the greatest challenges to the Deep Space Network (DSN) in the implementation and operation of new capabilities. The four probes that were to enter the atmosphere of Venus were turned on shortly before arrival at Venus, and the DSN had to acquire each of these probes in order to recover the telemetry being transmitted. Furthermore, a science experiment involving these probes descending through the atmosphere required a completed new data type to be generated at the ground stations. This new data type is known as the differential very long baseline interferometry. Discussions between ARC and JPL of the implementation requirements involved trade-offs in spacecraft design and led to a very successful return of science data. Specific implementation and operational techniques are discussed, not only for the prime mission, but also for the extended support to the Pioneer 12 spacecraft (in orbit around Venus) with its science instruments including that for radar observations of the planet.

A Filtering Method to Reveal Crystalline Patterns from Atom Probe Microscopy Desorption Maps

DTIC Science & Technology

2016-03-26

Gault, S.P. Ringer, J.M. Cairney, Atom probe crystallography : characterization of grain boundary orientation relationships in nanocrystalline...J.M. Cairney, Atom probe crystallography : atomic- scale 3-D orientation mapping, Scr. Mater. 66 (11) (2012) 907. L. Yao /MethodsX 3 (2016) 268–273 273

Active spacecraft potential control system selection for the Jupiter orbiter with probe mission

NASA Technical Reports Server (NTRS)

Beattie, J. R.; Goldstein, R.

1977-01-01

It is shown that the high flux of energetic plasma electrons and the reduced photoemission rate in the Jovian environment can result in the spacecraft developing a large negative potential. The effects of the electric fields produced by this charging phenomenon are discussed in terms of spacecraft integrity as well as charged particle and fields measurements. The primary area of concern is shown to be the interaction of the electric fields with the measuring devices on the spacecraft. The need for controlling the potential of the spacecraft is identified, and a system capable of active control of the spacecraft potential in the Jupiter environment is proposed. The desirability of using this system to vary the spacecraft potential relative to the ambient plasma potential is also discussed. Various charged particle release devices are identified as potential candidates for use with the spacecraft potential control system. These devices are evaluated and compared on the basis of system mass, power consumption, and system complexity and reliability.

Meteoroid/Debris Shielding

NASA Technical Reports Server (NTRS)

Christiansen, Eric L.

2003-01-01

This report provides innovative, low-weight shielding solutions for spacecraft and the ballistic limit equations that define the shield's performance in the meteoroid/debris environment. Analyses and hypervelocity impact testing results are described that have been used in developing the shields and equations. Spacecraft shielding design and operational practices described in this report are used to provide effective spacecraft protection from meteoroid and debris impacts. Specific shield applications for the International Space Station (ISS), Space Shuttle Orbiter and the CONTOUR (Comet Nucleus Tour) space probe are provided. Whipple, Multi-Shock and Stuffed Whipple shield applications are described.

Topography of Earth's moon

NASA Image and Video Library

2014-10-07

Topography of Earth's moon generated from data collected by the Lunar Orbiter Laser Altimeter, aboard NASA's Lunar Reconnaissance Orbiter, with the gravity anomalies bordering the Procellarum region superimposed in blue. The border structures are shown using gravity gradients calculated with data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission. These gravity anomalies are interpreted as ancient lava-flooded rift zones buried beneath the volcanic plains (or maria) on the nearside of the Moon. Launched as GRAIL A and GRAIL B in September 2011, the probes, renamed Ebb and Flow, operated in a nearly circular orbit near the poles of the moon at an altitude of about 34 miles (55 kilometers) until their mission ended in December 2012. The distance between the twin probes changed slightly as they flew over areas of greater and lesser gravity caused by visible features, such as mountains and craters, and by masses hidden beneath the lunar surface. The twin spacecraft flew in a nearly circular orbit until the end of the mission on Dec. 17, 2012, when the probes intentionally were sent into the moon's surface. NASA later named the impact site in honor of late astronaut Sally K. Ride, who was America's first woman in space and a member of the GRAIL mission team. GRAIL's prime and extended science missions generated the highest-resolution gravity field map of any celestial body. The map will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved. The GRAIL mission was managed by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, for NASA's Science Mission Directorate in Washington. The mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alabama. GRAIL was built by Lockheed Martin Space Systems in Denver. For more information about GRAIL, please visit grail.nasa.gov. Credit: NASA/Colorado School of Mines/MIT/GSFC/Scientific Visualization Studio

Validation of ISS Floating Potential Measurement Unit Electron Densities and Temperatures

NASA Technical Reports Server (NTRS)

Coffey, Victoria N.; Minow, Joseph I.; Parker, Linda N.; Bui, Them; Wright, Kenneth, Jr.; Koontz, Steven L.; Schneider, T.; Vaughn, J.; Craven, P.

2007-01-01

Validation of the Floating Potential Measurement Unit (FPMU) electron density and temperature measurements is an important step in the process of evaluating International Space Station spacecraft charging issues .including vehicle arcing and hazards to crew during extravehicular activities. The highest potentials observed on Space Station are due to the combined VxB effects on a large spacecraft and the collection of ionospheric electron and ion currents by the 160 V US solar array modules. Ionospheric electron environments are needed for input to the ISS spacecraft charging models used to predict the severity and frequency of occurrence of ISS charging hazards. Validation of these charging models requires comparing their predictions with measured FPMU values. Of course, the FPMU measurements themselves must also be validated independently for use in manned flight safety work. This presentation compares electron density and temperatures derived from the FPMU Langmuir probes and Plasma Impedance Probe against the independent density and temperature measurements from ultraviolet imagers, ground based incoherent scatter radar, and ionosonde sites.

Gradiometry coexperiments to the gravity probe B and step missions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tapley, M.; Breakwell, J.; Everitt, C.W.F.

1990-01-01

The Gravity Probe-B (GP-B) spacecraft, designed to test predictions of general relativity, will fly in the mid 1990s. It will carry four electrostatically suspended gyroscopes in a cryogenic environment and will have a drag-free control system to minimize disturbances on the gyroscopes. The Stanford Test of Equivalence Principle (STEP) spacecraft, to fly later, will carry a set of test masses under very similar conditions. The possibility of using differential measurements of the GP-B gyroscopes suspension forces and the STEP tests mass displacement readout to form single-axis gravity gradiometers is explored. It is shown that the noise in the suspension systemsmore » is sufficiently small in the relevant frequency range, and that enough information is collected to compensate for the spacecrafts' attitude motion. Finally, using Breakwell's flat-earth approximation, these experiments are compared to other geodesy experiments and predict the contribution they can make to the knowledge of the Earth's geopotential.« less

Cassini Spacecraft in a JPL Assembly Room

NASA Image and Video Library

2003-07-02

On October of 1997, a two-story-tall robotic spacecraft will begin a journey of many years to reach and explore the exciting realm of Saturn, the most distant planet that can easily be seen by the unaided human eye. In addition to Saturn's interesting atmosphere and interior, its vast system contains the most spectacular of the four planetary ring systems, numerous icy satellites with a variety of unique surface features. A huge magnetosphere teeming with particles that interact with the rings and moons, and the intriguing moon Titan, which is slightly larger than the planet Mercury, and whose hazy atmosphere is denser than that of Earth, make Saturn a fascinating planet to study. The Cassini mission is an international venture involving NASA, the European Space Agency (ESA), the Italian Space Agency (ASI), and several separate European academic and industrial partners. The mission is managed for NASA by JPL. The spacecraft will carry a sophisticated complement of scientific sensors to support 27 different investigations to probe the mysteries of the Saturn system. The large spacecraft will consist of an orbiter and ESA's Huygens Titan probe. The orbiter mass at launch will be nearly 5300 kg, over half of which is propellant for trajectory control. The mass of the Titan probe (2.7 m diameter) is roughly 350 kg. The mission is named in honor of the seventeenth-century, French-Italian astronomer Jean Dominique Cassini, who discovered the prominent gap in Saturn's main rings, as well as the icy moons Iapetus, Rhea, Dione, and Tethys. The ESA Titan probe is named in honor of the exceptional Dutch scientist Christiaan Huygens, who discovered Titan in 1655, followed in 1659 by his announcement that the strange Saturn "moons" seen by Galileo in 1610 were actually a ring system surrounding the planet. Huygens was also famous for his invention of the pendulum clock, the first accurate timekeeping device. http://photojournal.jpl.nasa.gov/catalog/PIA04603

Cassini Spacecraft in a JPL Assembly Room

NASA Technical Reports Server (NTRS)

2003-01-01

On October of 1997, a two-story-tall robotic spacecraft will begin a journey of many years to reach and explore the exciting realm of Saturn, the most distant planet that can easily be seen by the unaided human eye. In addition to Saturn's interesting atmosphere and interior, its vast system contains the most spectacular of the four planetary ring systems, numerous icy satellites with a variety of unique surface features. A huge magnetosphere teeming with particles that interact with the rings and moons, and the intriguing moon Titan, which is slightly larger than the planet Mercury, and whose hazy atmosphere is denser than that of Earth, make Saturn a fascinating planet to study.

The Cassini mission is an international venture involving NASA, the European Space Agency (ESA), the Italian Space Agency (ASI), and several separate European academic and industrial partners. The mission is managed for NASA by JPL. The spacecraft will carry a sophisticated complement of scientific sensors to support 27 different investigations to probe the mysteries of the Saturn system. The large spacecraft will consist of an orbiter and ESA's Huygens Titan probe. The orbiter mass at launch will be nearly 5300 kg, over half of which is propellant for trajectory control. The mass of the Titan probe (2.7 m diameter) is roughly 350 kg.

The mission is named in honor of the seventeenth-century, French-Italian astronomer Jean Dominique Cassini, who discovered the prominent gap in Saturn's main rings, as well as the icy moons Iapetus, Rhea, Dione, and Tethys. The ESA Titan probe is named in honor of the exceptional Dutch scientist Christiaan Huygens, who discovered Titan in 1655, followed in 1659 by his announcement that the strange Saturn 'moons' seen by Galileo in 1610 were actually a ring system surrounding the planet. Huygens was also famous for his invention of the pendulum clock, the first accurate timekeeping device.

Ganymede Global Geologic Map and Global Image Mosaic

NASA Image and Video Library

2014-02-12

To present the best information in a single view of Jupiter moon Ganymede, a global image mosaic was assembled, incorporating the best available imagery from NASA Voyager 1 and 2 spacecraft and NASA Galileo spacecraft.

Color Map of Ceres Elliptical Projection

NASA Image and Video Library

2016-03-22

This global map elliptical map from NASA Dawn spacecraft shows the surface of Ceres in enhanced color, encompassing infrared wavelengths beyond human visual range. Some areas near the poles are black where Dawn color imaging coverage is incomplete.

Cross-comparison of spacecraft-environment interaction model predictions applied to Solar Probe Plus near perihelion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchand, R.; Miyake, Y.; Usui, H.

2014-06-15

Five spacecraft-plasma models are used to simulate the interaction of a simplified geometry Solar Probe Plus (SPP) satellite with the space environment under representative solar wind conditions near perihelion. By considering similarities and differences between results obtained with different numerical approaches under well defined conditions, the consistency and validity of our models can be assessed. The impact on model predictions of physical effects of importance in the SPP mission is also considered by comparing results obtained with and without these effects. Simulation results are presented and compared with increasing levels of complexity in the physics of interaction between solar environmentmore » and the SPP spacecraft. The comparisons focus particularly on spacecraft floating potentials, contributions to the currents collected and emitted by the spacecraft, and on the potential and density spatial profiles near the satellite. The physical effects considered include spacecraft charging, photoelectron and secondary electron emission, and the presence of a background magnetic field. Model predictions obtained with our different computational approaches are found to be in agreement within 2% when the same physical processes are taken into account and treated similarly. The comparisons thus indicate that, with the correct description of important physical effects, our simulation models should have the required skill to predict details of satellite-plasma interaction physics under relevant conditions, with a good level of confidence. Our models concur in predicting a negative floating potential V{sub fl}∼−10V for SPP at perihelion. They also predict a “saturated emission regime” whereby most emitted photo- and secondary electron will be reflected by a potential barrier near the surface, back to the spacecraft where they will be recollected.« less

Systems design study of the Pioneer Venus spacecraft. Appendices to volume 1, sections 3-6 (part 1 of 3). [design of Venus probe windows

NASA Technical Reports Server (NTRS)

1973-01-01

The design is described of the Venus probe windows, which are required to measure solar flux, infrared flux, aureole, and cloud particles. Window heating and structural materials for the probe window assemblies are discussed along with the magnetometer. The command lists for science, power and communication requirements, telemetry sign characteristics, mission profile summary, mass properties of payloads, and failure modes are presented.

Mapping alternating current electroosmotic flow at the dielectrophoresis crossover frequency of a colloidal probe.

PubMed

Wang, Jingyu; Wei, Ming-Tzo; Cohen, Joel A; Ou-Yang, H Daniel

2013-07-01

AC electroosmotic (ACEO) flow above the gap between coplanar electrodes is mapped by the measurement of Stokes forces on an optically trapped polystyrene colloidal particle. E²-dependent forces on the probe particle are selected by amplitude modulation (AM) of the ACEO electric field (E) and lock-in detection at twice the AM frequency. E²-dependent DEP of the probe is eliminated by driving the ACEO at the probe's DEP crossover frequency. The location-independent DEP crossover frequency is determined, in a separate experiment, as the limiting frequency of zero horizontal force as the probe is moved toward the midpoint between the electrodes. The ACEO velocity field, uncoupled from probe DEP effects, was mapped in the region 1-9 μm above a 28 μm gap between the electrodes. By use of variously sized probes, each at its DEP crossover frequency, the frequency dependence of the ACEO flow was determined at a point 3 μm above the electrode gap and 4 μm from an electrode tip. At this location the ACEO flow was maximal at ∼117 kHz for a low salt solution. This optical trapping method, by eliminating DEP forces on the probe, provides unambiguous mapping of the ACEO velocity field. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Empirical correction for earth sensor horizon radiance variation

NASA Technical Reports Server (NTRS)

Hashmall, Joseph A.; Sedlak, Joseph; Andrews, Daniel; Luquette, Richard

1998-01-01

A major limitation on the use of infrared horizon sensors for attitude determination is the variability of the height of the infrared Earth horizon. This variation includes a climatological component and a stochastic component of approximately equal importance. The climatological component shows regular variation with season and latitude. Models based on historical measurements have been used to compensate for these systematic changes. The stochastic component is analogous to tropospheric weather. It can cause extreme, localized changes that for a period of days, overwhelm the climatological variation. An algorithm has been developed to compensate partially for the climatological variation of horizon height and at least to mitigate the stochastic variation. This method uses attitude and horizon sensor data from spacecraft to update a horizon height history as a function of latitude. For spacecraft that depend on horizon sensors for their attitudes (such as the Total Ozone Mapping Spectrometer-Earth Probe-TOMS-EP) a batch least squares attitude determination system is used. It is assumed that minimizing the average sensor residual throughout a full orbit of data results in attitudes that are nearly independent of local horizon height variations. The method depends on the additional assumption that the mean horizon height over all latitudes is approximately independent of season. Using these assumptions, the method yields the latitude dependent portion of local horizon height variations. This paper describes the algorithm used to generate an empirical horizon height. Ideally, an international horizon height database could be established that would rapidly merge data from various spacecraft to provide timely corrections that could be used by all.

NASA Tech Briefs, May 2007

NASA Technical Reports Server (NTRS)

2007-01-01

Topics include: Noise-Canceling Helmet Audio System; Program Analyzes Spacecraft/Ground Radio Links; Two-Way Communication Using RFID Equipment and Techniques; Six-Message Electromechanical Display System; Scanning Terahertz Heterodyne Imaging Systems; Master Clock and Time-Signal-Distribution System; Synchronous Phase-Resolving Flash Range Imaging; Integrated Radial Probe Transition From MMIC to Waveguide; Bar-Code System for a Microbiological Laboratory; MMIC Amplifier Produces Gain of 10 dB at 235 GHz; Mapping Nearby Terrain in 3D by Use of a Grid of Laser Spots; Digital Beam Deflectors Based Partly on Liquid Crystals; Narrow-Band WGM Optical Filters With Tunable FSRs; Better Finite-Element Analysis of Composite Shell Structures; Computing Spacecraft-Pointing Vectors for Limb Tracking; Enhanced Master Controller Unit Tester; Rover Graphical Simulator; Increasing Durability of Flame-Sprayed Strain Gauges; Multifunctional, High-Temperature Nanocomposites; Multilayer Impregnated Fibrous Thermal Insulation Tiles; Radiation-Shielding Polymer/Soil Composites; Film/Adhesive Processing Module for Fiber-Placement Processing of Composites; Fabrication of Submillimeter Axisymmetric Optical Components; Electrochemical Disposal of Hydrazines in Water; Statistical Model of Evaporating Multicomponent Fuel Drops; Resistively Heated SiC Nozzle for Generating Molecular Beams; Compact Packaging of Photonic Millimeter-Wave Receiver; Diffractive Combiner of Single-Mode Pump Laser-Diode Beams; Wide-Band, High-Quantum-Efficiency Photodetector; A Robustly Stabilizing Model Predictive Control Algorithm; Modeling Evaporation of Drops of Different Kerosenes; Development of Vapor-Phase Catalytic Ammonia Removal System; Several Developments in Space Tethers; Design Concept for a Nuclear Reactor-Powered Mars Rover; Formation-Initialization Algorithm for N Spacecraft; and DNSs of Multicomponent Gaseous and Drop-Laden Mixing Layers Achieving Transition to Turbulence.

An Overview of the Topography of Mars from the Mars Orbiter Laser Altimeter (MOLA)

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria T.

2000-01-01

The Mars Global Surveyor (MGS) spacecraft has now completed more than half of its one-Mars-year mission to globally map Mars. During the MGS elliptical and circular orbit mapping phases, the Mars Orbiter Laser Altimeter (MOLA), an instrument on the MGS payload, has collected over 300 million precise elevation measurements. MOLA measures the range from the MGS spacecraft to the Martian surface and to atmospheric reflections. Range is converted to topography through knowledge of the MGS spacecraft orbit. Ranges from MOLA have resulted in a precise global topographic map of Mars. The instrument has also provided measurements of the width of the backscattered optical pulse and of the 1064 nm reflectivity of the Martian surface and atmosphere. The range resolution of the MOLA instrument is 37.5 cm and the along-track resolution of MOLA ground shots is approx. 300 m; the across-track spacing depends on latitude and time in the mapping orbit. The best current topographic grid has a spatial resolution of approx. 1/16 deg and vertical accuracy of approx. one meter. Additional information is contained in the original extended abstract.

Evaluation of SNP Data from the Malus Infinium Array Identifies Challenges for Genetic Analysis of Complex Genomes of Polyploid Origin

PubMed Central

Troggio, Michela; Šurbanovski, Nada; Bianco, Luca; Moretto, Marco; Giongo, Lara; Banchi, Elisa; Viola, Roberto; Fernández, Felicdad Fernández; Costa, Fabrizio; Velasco, Riccardo; Cestaro, Alessandro; Sargent, Daniel James

2013-01-01

High throughput arrays for the simultaneous genotyping of thousands of single-nucleotide polymorphisms (SNPs) have made the rapid genetic characterisation of plant genomes and the development of saturated linkage maps a realistic prospect for many plant species of agronomic importance. However, the correct calling of SNP genotypes in divergent polyploid genomes using array technology can be problematic due to paralogy, and to divergence in probe sequences causing changes in probe binding efficiencies. An Illumina Infinium II whole-genome genotyping array was recently developed for the cultivated apple and used to develop a molecular linkage map for an apple rootstock progeny (M432), but a large proportion of segregating SNPs were not mapped in the progeny, due to unexpected genotype clustering patterns. To investigate the causes of this unexpected clustering we performed BLAST analysis of all probe sequences against the ‘Golden Delicious’ genome sequence and discovered evidence for paralogous annealing sites and probe sequence divergence for a high proportion of probes contained on the array. Following visual re-evaluation of the genotyping data generated for 8,788 SNPs for the M432 progeny using the array, we manually re-scored genotypes at 818 loci and mapped a further 797 markers to the M432 linkage map. The newly mapped markers included the majority of those that could not be mapped previously, as well as loci that were previously scored as monomorphic, but which segregated due to divergence leading to heterozygosity in probe annealing sites. An evaluation of the 8,788 probes in a diverse collection of Malus germplasm showed that more than half the probes returned genotype clustering patterns that were difficult or impossible to interpret reliably, highlighting implications for the use of the array in genome-wide association studies. PMID:23826289

KSC-04pd0940

NASA Image and Video Library

2004-04-20

KENNEDY SPACE CENTER, FLA. - The Gravity Probe B spacecraft, atop a Boeing Delta II vehicle, launches at 12:57:24 p.m. EDT from Space Launch Complex 2 at Vandenberg Air Force Base, Calif. Gravity Probe B is the relativity gyroscope experiment being developed by NASA and Stanford University to test two extraordinary, unverified predictions of Albert Einstein's general theory of relativity.

KSC-04PD-0940

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. The Gravity Probe B spacecraft, atop a Boeing Delta II vehicle, launches at 12:57:24 p.m. EDT from Space Launch Complex 2 at Vandenberg Air Force Base, Calif. Gravity Probe B is the relativity gyroscope experiment being developed by NASA and Stanford University to test two extraordinary, unverified predictions of Albert Einstein's general theory of relativity.

STS-34 Galileo processing at KSC's SAEF-2 planetary spacecraft facility

NASA Image and Video Library

1989-07-21

At the Kennedy Space Center's (KSC's) Spacecraft and Assembly Encapsulation Facility 2 (SAEF-2), the planetary spacecraft checkout facility, clean-suited technicians work on the Galileo spacecraft prior to moving it to the Vehicle Processing Facility (VPF) for mating with the inertial upper stage (IUS). Galileo is scheduled for launch aboard Atlantis, Orbiter Vehicle (OV) 104, on Space Shuttle Mission STS-34 in October 1989. It will be sent to the planet Jupiter, a journey which will taken more than six years to complete. In December 1995 as the two and one half ton spacecraft orbits Jupiter with its ten scientific instruments, a probe will be released to parachute into the Jovian atmosphere. NASA's Jet Propulsion Laboratory (JPL) manages the Galileo project. View provided by KSC.

Study of the adaptability of existing hardware designs to a Pioneer Saturn/Uranus probe

NASA Technical Reports Server (NTRS)

1973-01-01

The basic concept of designing a scientific entry probe for the expected range of environments at Saturn or Uranus and making the probe compatible with the interface constraints of the Pioneer spacecraft was investigated for launches in the early 1980's. It was found that the amount of hardware commonality between that used in the Pioneer Venus program and that for the Saturn/Uranus probe was approximately 85%. It is recommended that additional development studies be conducted to improve the hardware definitions of the probe design for the following: heat shield, battery, nose cap jettisoning, and thermal control insulation.

Pieces of the Huygens probe internal insulating foam await inspection after removal from the probe i

NASA Technical Reports Server (NTRS)

1997-01-01

Pieces of the Huygens probe internal insulating foam await inspection after removal from the probe in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station.

An employee sews thermal insulation material on the back cover and heat shield of the Huygens probe

NASA Technical Reports Server (NTRS)

1997-01-01

An employee in the Payload Hazardous Servicing Facility (PHSF) sews thermal insulation material on the back cover and heat shield of the Huygens probe during prelaunch processing, testing and integration in that facility. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.

An employee works on the top side of the experiment platform for the Huygens probe in the PHSF

NASA Technical Reports Server (NTRS)

1997-01-01

An employee in the Payload Hazardous Servicing Facility (PHSF) works on the top side of the experiment platform for the Huygens probe that will accompany the Cassini orbiter to Saturn during prelaunch processing, testing and integration in that facility. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.

Rotating Globe of Ganymede Geology

NASA Image and Video Library

2014-02-12

This is a frame from an animation of a rotating globe of Jupiter moon Ganymede, with a geologic map superimposed over a global color mosaic, incorporating the best available imagery from NASA Voyager 1 and 2 spacecraft, and Galileo spacecraft.

Map of Rhea - January 2011

NASA Image and Video Library

2011-05-02

This global digital map of Rhea was created using data taken during NASA Cassini and Voyager spacecraft flybys. This map contains data from Cassini Jan. 11, 2011, flyby of Rhea. Six Voyager images fill gaps in Cassini coverage of the north pole.

Autonomy Architectures for a Constellation of Spacecraft

NASA Technical Reports Server (NTRS)

Barrett, Anthony

2000-01-01

Until the past few years, missions typically involved fairly large expensive spacecraft. Such missions have primarily favored using older proven technologies over more recently developed ones, and humans controlled spacecraft by manually generating detailed command sequences with low-level tools and then transmitting the sequences for subsequent execution on a spacecraft controller. This approach toward controlling a spacecraft has worked spectacularly on previous missions, but it has limitations deriving from communications restrictions - scheduling time to communicate with a particular spacecraft involves competing with other projects due to the limited number of deep space network antennae. This implies that a spacecraft can spend a long time just waiting whenever a command sequence fails. This is one reason why the New Millennium program has an objective to migrate parts of mission control tasks onboard a spacecraft to reduce wait time by making spacecraft more robust. The migrated software is called a "remote agent" and has 4 components: a mission manager to generate the high level goals, a planner/scheduler to turn goals into activities while reasoning about future expected situations, an executive/diagnostics engine to initiate and maintain activities while interpreting sensed events by reasoning about past and present situations, and a conventional real-time subsystem to interface with the spacecraft to implement an activity's primitive actions. In addition to needing remote planning and execution for isolated spacecraft, a trend toward multiple-spacecraft missions points to the need for remote distributed planning and execution. The past few years have seen missions with growing numbers of probes. Pathfinder has its rover (Sojourner), Cassini has its lander (Huygens), and the New Millenium Deep Space 3 (DS3) proposal involves a constellation of 3 spacecraft for interferometric mapping. This trend is expected to continue to progressively larger fleets. For example, one mission proposed to succeed DS3 would have 18 spacecraft flying in formation in order to detect earth-sized planets orbiting other stars. A proposed magnetospheric constellation would involve 5 to 500 spacecraft in Earth orbit to measure global phenomena within the magnetosphere. This work describes and compares three autonomy architectures for a system that continuously plans to control a fleet of spacecraft using collective mission goals instead of goals or command sequences for each spacecraft. A fleet of self-commanding spacecraft would autonomously coordinate itself to satisfy high level science and engineering goals in a changing partially-understood environment making feasible the operation of tens or even a hundred spacecraft (such as for interferometry or plasma physics missions). The easiest way to adapt autonomous spacecraft research to controlling constellations involves treating the constellation as a single spacecraft. Here one spacecraft directly controls the others as if they were connected. The controlling "master" spacecraft performs all autonomy reasoning, and the slaves only have real-time subsystems to execute the master's commands and transmit local telemetry/observations. The executive/diagnostics module starts actions and the master's real-time subsystem controls the action either locally or remotely through a slave. While the master/slave approach benefits from conceptual simplicity, it relies on an assumption that the master spacecraft's executive can continuously monitor the slaves' real-time subsystems, and this relies on high-bandwidth highly-reliable communications. Since unintended results occur fairly rarely, one way to relax the bandwidth requirements involves only monitoring unexpected events in spacecraft. Unfortunately, this disables the ability to monitor for unexpected events between spacecraft and leads to a host of coordination problems among the slaves. Also, failures in the communications system can result in losing slaves. The other two architectures improve robustness while reducing communications by progressively distributing more of the other three remote agent components across the constellation. In a teamwork architecture, all spacecraft have executives and real-time subsystems - only the leader has the planner/scheduler and mission manager. Finally, distributing all remote agent components leads to a peer-to-peer approach toward constellation control.

Spacecraft potential effects on the Dynamics Explorer 2 satellite

NASA Technical Reports Server (NTRS)

Anderson, P. C.; Hanson, W. B.; Coley, W. R.; Hoegy, W. R.

1994-01-01

The relationship between the plasma environment and spacecraft potential is examined for the Dynamics Explorer 2 (DE 2) spacecraft in an attempt to improve the accuracy of ion drift measurements by the retarding potential analyzer (RPA). Because of the DE 2 orbit characteristics (apogee near 1000 km and perigee near 300 km) and the configuration of conducting surfaces on the spacecraft, thermal electrons and ions constituted the only significant contributions to the charging currents to the spacecraft surface for the majority of geophysical conditions encountered. The geomagnetic field had considerable effect on the spacecraft potential due to magnetic field confinement of the electrons as well as to the V x B electric field resulting from the movement of the spacecraft across magnetic field lines. Using a database of inferred spacecraft potentials from the RPA, measured electron temperatures from the Langmuir probe (LANG), and calculated V x B electric fields, we derive an algorithm for determining the spacecraft potential (at the location of the RPA on the spacecraft) for any point of the DE 2 orbit. Knowledge of the spacecraft potential subsequently allows us to retrieve relatively accurate ion drifts from the RPA data.

Distributed operations as applied in a large multi-instrument space mission: lessons learned from the Cassini-Huygens Program

NASA Technical Reports Server (NTRS)

Cheng, L. Y.; Larsen, B.

2004-01-01

Launched in 1997, the Cassini-Huygens Mission sent the largest interplanetary spacecraft ever built in the service of science. Carrying a suite of 12 scientific instruments and an atmospheric entry probe, this complex spacecraft to explore the Saturn system may not have gotten off the ground without undergoing significant design changes and cost reductions.

Aeronautics and space report of the President, 1980 activities

NASA Technical Reports Server (NTRS)

1981-01-01

The year's achievements in the areas of communication, Earth resources, environment, space sciences, transportation, and space energy are summarized and current and planned activities in these areas at the various departments and agencies of the Federal Government are summarized. Tables show U.S. and world spacecraft records, spacecraft launchings for 1980, and scientific payload anf probes launched 1975-1980. Budget data are included.

Investigation of Possible Electromagnetic Disturbances caused by Spacecraft-Plasma Interactions at 4 Radii

NASA Technical Reports Server (NTRS)

Okada, M.; Tsurutani, B. T.; Goldstein, G. E.; Matsumoto, H.; Brinca, A. L.; Kellogg, P. J.

1995-01-01

The proposed Small Solar Probe mission features a close approach to the sun with a perihelion of 4 radii. Carbon molecules emitted from the spacecraft's heat shield will become ionized by electron impact and photoionization. The newly created ions and electrons may generate electromagnetic and electrostatic plasma waves which are possible sources of interference with in-situ plasma measurements.

Artist concept of Magellan spacecraft above Venusian surface

NASA Technical Reports Server (NTRS)

1988-01-01

Artist concept shows Magellan spacecraft in cruise configuration oriented above Venusian surface, during data collection and radar mapping sequence. Solar panels are deployed and low-gain and high gain antennas, altimeter antenna, thermal control louvers, forward equipment module, equipment bus with thermal control louvers, and control rocket engine module are visible. The continued quest for detailed topographic measurements of Venus will again be undertaken in April 1989 by Magellan, named after the 16th century Portuguese explorer. Magellan will orbit Venus about once every three hours, acquiring radar data for 37 minutes of each orbit when it is closest to the surface. Using an advanced instrument called a synthetic aperature radar (SAR), it will map more than 90 per cent of the surface with resolution ten times better than the best prior spacecraft. Magellan is managed by the Jet Propulsion Laboratory (JPL); Martin Marietta is developing the spacecraft and Hughes Aircraft Company,

Searching for organics on the dwarf planet Ceres

NASA Astrophysics Data System (ADS)

Nayak, Michael

The Herschel Space Observatory recently detected the presence of water vapor in observations of Ceres, bringing it into the crosshairs of the search for the building blocks of life in the solar system. I present a mission concept designed in collaboration with the NASA Ames Research Center for a two-probe mission to the dwarf planet Ceres, utilizing a pair of small low-cost spacecraft. The primary spacecraft will carry both a mass and an infrared spectrometer to characterize the detected vapor. Shortly after its arrival a second and largely similar spacecraft will impact Ceres to create an impact ejecta "plume" timed to enable a rendezvous and sampling by the primary spacecraft. This enables additional subsurface chemistry, volatile content and material characterization, and new science complementary to the Dawn spacecraft, the first to arrive at Ceres. Science requirements, candidate instruments, rendezvous trajectories, spacecraft design and comparison with Dawn science are detailed.

KSC-03pd2743

NASA Image and Video Library

2003-07-11

VANDENBERG AFB, CALIF. - Enclosed in a canister, the Gravity Probe B (GP-B) spacecraft arrives at the spacecraft processing facility on North Vandenberg Air Force Base . Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einstein’s general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earth’s rotation drags space and time around with it). Once in orbit, for 18 months each gyroscope’s spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASA’s Marshall Space Flight Center.

Initial Results from the Floating Potential Measurement Unit aboard the International Space Station

NASA Technical Reports Server (NTRS)

Wright, Kenneth H., Jr.; Swenson, Charles; Thompson, Don; Barjatya, Aroh; Koontz, Steven L.; Schneider, Todd; Vaughn, Jason; Minow, Joseph; Craven, Paul; Coffey, Victoria;

Low-Temperature Spacecraft: Challenges/Opportunities

NASA Technical Reports Server (NTRS)

Dickman, J. E.; Patterson, R. L.; Overton, E.; Hammoud, A. N.; Gerber, S. S.

2001-01-01

Imagine sending a spacecraft into deep space that operates at the ambient temperature of its environment rather than hundreds of degrees Kelvin warmer. The average temperature of a spacecraft warmed only by the sun drops from 279 K near the Earth's orbit to 90 K near the orbit of Saturn, and to 44 K near Pluto's orbit. At present, deep space probes struggle to maintain an operating temperature near 300 K for the onboard electronics. To warm the electronics without consuming vast amounts of electrical energy, radioisotope heater units (RHUs) are used in vast numbers. Unfortunately, since RHU are always 'on', an active thermal management system is required to reject the excess heat. A spacecraft designed to operate at cryogenic temperatures and shielded from the sun by a large communication dish or solar cell array could be less complex, lighter, and cheaper than current deep space probes. Before a complete low-temperature spacecraft becomes a reality, there are several challenges to be met. Reliable cryogenic power electronics is one of the major challenges. The Low-Temperature Power Electronics Research Group at NASA Glenn Research Center (GRC) has demonstrated the ability of some commercial off the shelf power electronic components to operate at temperatures approaching that of liquid nitrogen (77 K). Below 77 K, there exists an opportunity for the development of reliable semiconductor power switching technologies other than bulk silicon CMOS. This paper will report on the results of NASA GRC's Low-Temperature Power Electronics Program and discuss the challenges to (opportunities for) the creation of a low-temperature spacecraft.

Asteroid Bennu Temperature Maps for OSIRIS-REx Spacecraft and Instrument Thermal Analyses

NASA Technical Reports Server (NTRS)

Choi, Michael K.; Emery, Josh; Delbo, Marco

2014-01-01

A thermophysical model has been developed to generate asteroid Bennu surface temperature maps for OSIRIS-REx spacecraft and instrument thermal design and analyses at the Critical Design Review (CDR). Two-dimensional temperature maps for worst hot and worst cold cases are used in Thermal Desktop to assure adequate thermal design margins. To minimize the complexity of the Bennu geometry in Thermal Desktop, it is modeled as a sphere instead of the radar shape. The post-CDR updated thermal inertia and a modified approach show that the new surface temperature predictions are more benign. Therefore the CDR Bennu surface temperature predictions are conservative.

Lossless Compression of Classification-Map Data

NASA Technical Reports Server (NTRS)

Hua, Xie; Klimesh, Matthew

2009-01-01

A lossless image-data-compression algorithm intended specifically for application to classification-map data is based on prediction, context modeling, and entropy coding. The algorithm was formulated, in consideration of the differences between classification maps and ordinary images of natural scenes, so as to be capable of compressing classification- map data more effectively than do general-purpose image-data-compression algorithms. Classification maps are typically generated from remote-sensing images acquired by instruments aboard aircraft (see figure) and spacecraft. A classification map is a synthetic image that summarizes information derived from one or more original remote-sensing image(s) of a scene. The value assigned to each pixel in such a map is the index of a class that represents some type of content deduced from the original image data for example, a type of vegetation, a mineral, or a body of water at the corresponding location in the scene. When classification maps are generated onboard the aircraft or spacecraft, it is desirable to compress the classification-map data in order to reduce the volume of data that must be transmitted to a ground station.

The Gravity Probe B Experiment

NASA Technical Reports Server (NTRS)

Kolodziejczak, Jeffrey

2008-01-01

This presentation briefly describes the Gravity Probe B (GP-B) Experiment which is designed to measure parts of Einstein's general theory of relativity by monitoring gyroscope orientation relative to a distant guide star. To measure the miniscule angles predicted by Einstein's theory, it was necessary to build near-perfect gyroscopes that were approximately 50 million times more precise than the best navigational gyroscopes. A telescope mounted along the central axis of the dewar and spacecraft provided the experiment's pointing reference to a guide star. The telescope's image divide precisely split the star's beam into x-axis and y-axis components whose brightness could be compared. GP-B's 650-gallon dewar, kept the science instrument inside the probe at a cryogenic temperature for 17.3 months and also provided the thruster propellant for precision attitude and translation control. Built around the dewar, the GP-B spacecraft was a total-integrated system, comprising both the space vehicle and payload, dedicated as a single entity to experimentally testing predictions of Einstein's theory.

The Interaction of the Solar Wind with Solar Probe Plus - 3D Hybrid Simulation. Report 2: The Study for the Distance 9.5Rs

NASA Technical Reports Server (NTRS)

Lipatov, Alexander S.; Sittler, Edward C.; Hartle, Richard E.; Cooper, John F.

2010-01-01

Our paper is a 2.5D and 3D numerical plasma models of the interaction of the solar wind (SW) with the Solar Probe Plus spacecraft (SPPSC). These results should be interpreted as a basic plasma model for which the derived SW interaction with spacecraft (SC) could have consequences for both plasma wave and electron plasma measurements on board SC in the inner heliosphere. We observe an excitation of the low frequency Alfven and whistler type wave directed by the magnetic field with an amplitude of the electromagnetic field oscillation about of (0.015-0.06) V/m. The compression waves and the jumps in an electric field with an amplitude of about 1.5 V/m and (12-18) V/m were also observed. The observed strong electromagnetic perturbations may be a crucial point in the electromagnetic measurements, which were planned in future Solar Probe Plus mission.

1400898

NASA Image and Video Library

2014-07-01

THE SOLAR PROBE PLUS CUP INSTRUMENT WILL BE PART OF THE SOLAR PROBE PLUS MISSION TO STUDY THE SUN. THE CUP WILL FLY ON THE SPACECRAFT ON THE OUTSIDE OF THE SHIELD AND WILL "CATCH" CHARGED PARTICLES FROM THE SUN AND ANALYZE THEM. A TEAM FROM THE HARVARD SMITHSONIAN ASTROPHYSICS OBSERVATORY IS BUILDING THIS INSTRUMENT AND TESTED AN ENGINEERING MODEL OF THE CUP IN AN ENVIRONMENTAL TEST FACILITY AT NASA'S MARSHALL SPACE FLIGHT CENTER.INSIDE THE VACUUM CHAMBER, THE PROBE WAS EXPOSED TO AN ENVIRONMENTAL CONDITIONS SIMILAR TO THOSE FOUND IN SPACE

Systems-level study of a nonsurvivable Jupiter turbopause probe. Volume 1: Summary

NASA Technical Reports Server (NTRS)

Wiltshire, R. S.

1972-01-01

The design of a space probe to explore the atmosphere of the planet Jupiter is discussed. Five major areas were considered: (1) definition of science requirements, (2) mission evaluation, (3) definition of probe system, (4) definition of spacecraft support requirements, and (5) nonequilibrium flow field analysis for communications blackout evaluation. The overall mission and system design are emphasized. The integration of the various technologies into complete systems designs is described. Results showed that a nonsurvivable turbopause probe mission to Jupiter with adequate data return to meet the science objectives is feasible and practical.

Conjunction of Photovoltaic and Thermophotovoltaic Power Production in Spacecraft Power Systems

DTIC Science & Technology

2015-09-01

photovoltaic ( PV ) arrays, which draw electrical energy from the most prominent power source in our solar system, the Sun. These arrays are large, and pose...freemaps/1000px/dni/SolarGIS- Solar -map-DNI-World- map-en.png By contrast, spacecraft PV power production systems are not so limited. With the...operating parameters for a given solar cell, and PMax is generally the described Pout from which the PV cell’s efficiency is calculated. A PV cell’s

A study of an orbital radar mapping mission to Venus. Volume 1: Summary

NASA Technical Reports Server (NTRS)

1973-01-01

A preliminary design of a Venus radar mapping orbiter mission and spacecraft was developed. The important technological problems were identified and evaluated. The study was primarily concerned with trading off alternate ways of implementing the mission and examining the most attractive concepts in order to assess technology requirements. Compatible groupings of mission and spacecraft parameters were analyzed by examining the interaction of their functioning elements and assessing their overall cost effectiveness in performing the mission.

Spacecraft charging and ion wake formation in the near-Sun environment

NASA Astrophysics Data System (ADS)

Ergun, R. E.; Malaspina, D. M.; Bale, S. D.; McFadden, J. P.; Larson, D. E.; Mozer, F. S.; Meyer-Vernet, N.; Maksimovic, M.; Kellogg, P. J.; Wygant, J. R.

2010-07-01

A three-dimensional, self-consistent code is employed to solve for the static potential structure surrounding a spacecraft in a high photoelectron environment. The numerical solutions show that, under certain conditions, a spacecraft can take on a negative potential in spite of strong photoelectron currents. The negative potential is due to an electrostatic barrier near the surface of the spacecraft that can reflect a large fraction of the photoelectron flux back to the spacecraft. This electrostatic barrier forms if (1) the photoelectron density at the surface of the spacecraft greatly exceeds the ambient plasma density, (2) the spacecraft size is significantly larger than local Debye length of the photoelectrons, and (3) the thermal electron energy is much larger than the characteristic energy of the escaping photoelectrons. All of these conditions are present near the Sun. The numerical solutions also show that the spacecraft's negative potential can be amplified by an ion wake. The negative potential of the ion wake prevents secondary electrons from escaping the part of spacecraft in contact with the wake. These findings may be important for future spacecraft missions that go nearer to the Sun, such as Solar Orbiter and Solar Probe Plus.

Nick Sagan Reflects on Voyager 1 and the Golden Record

NASA Astrophysics Data System (ADS)

Showstack, Randy

2013-10-01

When scientists confirmed on 12 September that NASA's Voyager 1 spacecraft had entered interstellar space (Eos, 94(39), 339, doi:10.1002/2013EO390003), the probe was acknowledged as the first human-made object to travel into that realm. The probe and its twin, Voyager 2, each carry a 12-inch gold-plated copper disk, known as the Golden Record.

KSC-97pc729

NASA Image and Video Library

1997-04-22

An employee in the Payload Hazardous Servicing Facility (PHSF) sews thermal insulation material on the front heat shield of the Huygens probe during prelaunch processing testing and integration in that facility, with the probe’s back cover in the background. The Huygens probe and the Cassini orbiter being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn’s largest moon, Titan. The orbiter was designed and assembled at NASA’s Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004

Molecular cytogenetic mapping of 24 CEPH YACs and 24 gene-specific large insert probes to chromosome 17.

PubMed

Bärlund, M; Nupponen, N N; Karhu, R; Tanner, M M; Paavola, P; Kallioniemi, O P; Kallioniemi, A

1998-01-01

Defining boundaries of chromosomal rearrangements at the molecular level would benefit from landmarks that link the cytogenetic map to physical, genetic, and transcript maps, as well as from large-insert FISH probes for such loci to detect numerical and structural rearrangements in metaphase or interphase cells. Here, we determined the locations of 24 genetically mapped CEPH-Mega YACs along the FLpter scale (fractional length from p-telomere) by quantitative fluorescence in situ hybridization analysis. This generated a set of cytogenetically mapped probes for chromosome 17 with an average spacing of about 5 cM. We then developed large-insert YAC, BAC, PAC, or P1 clones to the following 24 known genes, and determined refined map locations along the same FLpter scale: pter-TP53-TOP3-cen-TNFAIP1-ERBB2-TOP2A- BRCA1-TCF11-NME1-HLF-ZNF147/CL N80-BCL5/MPO/SFRS1-TBX2-PECAM1-DDX5/ PRKCA-ICAM2-GH1/PRKAR1A-GRB2-CDK3 /FKHL13-qter. Taken together, these 48 cytogenetically mapped large-insert probes provide tools for the molecular analysis of chromosome 17 rearrangements, such as mapping amplification, deletion, and translocation breakpoints in this chromosome, in cancer and other diseases.

Hyperspectral Feature Detection Onboard the Earth Observing One Spacecraft using Superpixel Segmentation and Endmember Extraction

NASA Technical Reports Server (NTRS)

Thompson, David R.; Bornstein, Benjamin; Bue, Brian D.; Tran, Daniel Q.; Chien, Steve A.; Castano, Rebecca

2012-01-01

We present a demonstration of onboard hyperspectral image processing with the potential to reduce mission downlink requirements. The system detects spectral endmembers and then uses them to map units of surface material. This summarizes the content of the scene, reveals spectral anomalies warranting fast response, and reduces data volume by two orders of magnitude. We have integrated this system into the Autonomous Science craft Experiment for operational use onboard the Earth Observing One (EO-1) Spacecraft. The system does not require prior knowledge about spectra of interest. We report on a series of trial overflights in which identical spacecraft commands are effective for autonomous spectral discovery and mapping for varied target features, scenes and imaging conditions.

The Lewis Research Center geomagnetic substorm simulation facility

NASA Technical Reports Server (NTRS)

Berkopec, F. D.; Stevens, N. J.; Sturman, J. C.

1977-01-01

A simulation facility was established to determine the response of typical spacecraft materials to the geomagnetic substorm environment and to evaluate instrumentation that will be used to monitor spacecraft system response to this environment. Space environment conditions simulated include the thermal-vacuum conditions of space, solar simulation, geomagnetic substorm electron fluxes and energies, and the low energy plasma environment. Measurements for spacecraft material tests include sample currents, sample surface potentials, and the cumulative number of discharges. Discharge transients are measured by means of current probes and oscilloscopes and are verified by a photomultiplier. Details of this facility and typical operating procedures are presented.

Charge to Road Map Development Sessions

NASA Technical Reports Server (NTRS)

Barth, Janet

2004-01-01

Develop a road map for new standard Model applications radiation belt models. Model applications: Spacecraft and instruments. Reduce risk. Reduce cost. Improve performance. Increase system lifetime. Reduce risk to astronauts.

Outer planet entry probe system study. Volume 4: Common Saturn/Uranus probe studies

NASA Technical Reports Server (NTRS)

1973-01-01

Results are summarized of a common scientific probe study to explore the atmospheres of Saturn and Uranus. This was a three-month follow-on effort to the Outer Planet Entry Probe System study. The report presents: (1) a summary, conclusions and recommendations of this study, (2) parametric analysis conducted to support the two system definitions, (3) common Saturn/Uranus probe system definition using the Science Advisory Group's exploratory payload and, (4) common Saturn/Uranus probe system definition using an expanded science complement. Each of the probe system definitions consists of detailed discussions of the mission, science, system and subsystems including telecommunications, data handling, power, pyrotechnics, attitude control, structures, propulsion, thermal control and probe-to-spacecraft integration. References are made to the contents of the first three volumes where it is feasible to do so.

Line drawing of the Galileo spacecraft's encounters on its way to Jupiter

NASA Technical Reports Server (NTRS)

1989-01-01

Line drawing charts the Galileo spacecraft's launch from low Earth orbit and its three planetary and two asteroid encounters in the course of its gravity-assisted flight to Jupiter. These encounters include Venus (February 1990), two Earth passes (December 1990 and December 1992), and the asteroids Gaspra and Ida in the asteroid belt. Galileo will release a probe and will arrive at Jupiter, 12-07-95.

Line drawing of the Galileo spacecraft's encounters on its way to Jupiter

NASA Image and Video Library

1989-09-11

Line drawing charts the Galileo spacecraft's launch from low Earth orbit and its three planetary and two asteroid encounters in the course of its gravity-assisted flight to Jupiter. These encounters include Venus (February 1990), two Earth passes (December 1990 and December 1992), and the asteroids Gaspra and Ida in the asteroid belt. Galileo will release a probe and will arrive at Jupiter, 12-07-95.

Adaptive structures flight experiments

NASA Astrophysics Data System (ADS)

Martin, Maurice

The topics are presented in viewgraph form and include the following: adaptive structures flight experiments; enhanced resolution using active vibration suppression; Advanced Controls Technology Experiment (ACTEX); ACTEX program status; ACTEX-2; ACTEX-2 program status; modular control patch; STRV-1b Cryocooler Vibration Suppression Experiment; STRV-1b program status; Precision Optical Bench Experiment (PROBE); Clementine Spacecraft Configuration; TECHSAT all-composite spacecraft; Inexpensive Structures and Materials Flight Experiment (INFLEX); and INFLEX program status.

Adaptive Structures Flight Experiments

NASA Technical Reports Server (NTRS)

Martin, Maurice

1992-01-01

The topics are presented in viewgraph form and include the following: adaptive structures flight experiments; enhanced resolution using active vibration suppression; Advanced Controls Technology Experiment (ACTEX); ACTEX program status; ACTEX-2; ACTEX-2 program status; modular control patch; STRV-1b Cryocooler Vibration Suppression Experiment; STRV-1b program status; Precision Optical Bench Experiment (PROBE); Clementine Spacecraft Configuration; TECHSAT all-composite spacecraft; Inexpensive Structures and Materials Flight Experiment (INFLEX); and INFLEX program status.

MMS, Van Allen Probes, and Ground-based Magnetometer Observations of a Compression-induced EMIC Wave Event

NASA Astrophysics Data System (ADS)

Capman, N.; Engebretson, M.; Posch, J. L.; Cattell, C. A.; Tian, S.; Wygant, J. R.; Kletzing, C.; Lessard, M.; Anderson, B. J.; Russell, C. T.; Reeves, G. D.; Fuselier, S. A.

2016-12-01

A 0.5-1.0 Hz electromagnetic ion cyclotron (EMIC) wave event was observed on December 14, 2015 from 13:26 to 13:28 UT at the four MMS satellites (L= 9.5, MLT= 13.0, MLAT= -24.4, peak amplitude 7 nT), and both Van Allen probes (RBSP-A: L= 5.7, MLT= 12.8, MLAT= 19.5, peak amplitude 5 nT; RBSP-B: L= 4.3, MLT= 14.2, MLAT= 11.3, peak amplitude 1 nT). On the ground, it was observed by search coil magnetometers at Halley Bay and South Pole, Antarctica, and Sondrestromfjord, Greenland, and by fluxgate magnetometers of the MACCS array at Pangnirtung and Cape Dorset in Arctic Canada. This event was preceded by a small increase of the solar wind pressure of 3 nPa from 13:10 to 13:20 UT. The proton distributions at Van Allen probe A confirm that the compression increased the pitch angle anisotropy in 10 keV ring current protons. The wave forms were very similar at the four MMS spacecraft indicating that the coherence-scale of the wave packets is larger than the inter-spacecraft separations of 20 km at the time. Inter-comparison of the wave signals at the four MMS spacecraft are used to assess the characteristics of the waves and estimate their spatial scales transverse and parallel to the background magnetic field.

Project Longshot

NASA Technical Reports Server (NTRS)

West, J. Curtis; Chamberlain, Sally A.; Stevens, Robert; Pagan, Neftali

1989-01-01

Project Longshot is an unmanned probe to our nearest star system, Alpha Centauri, 4.3 light years away. The Centauri system is a trinary system consisting of two central stars (A and B) orbiting a barycenter, and a third (Proxima Centauri) orbiting the two. The system is a declination of -67 degrees. The goal is to reach the Centauri system in 50 years. This time space was chosen because any shorter time would be impossible of the relativistic velocities involved, and any greater time would be impossible because of the difficulty of creating a spacecraft with such a long lifetime. Therefore, the following mission profile is proposed: (1) spacecraft is assembled in Earth orbit; (2) spacecraft escapes Earth and Sun in the ecliptic with a single impulse maneuver; (3) spacecraft changed declination to point toward Centauri system; (4) spacecraft accelerates to 0.1c; (5) spacecraft coasts at 0.1c for 41 years; (6) spacecraft decelerates upon reaching Centauri system; and (7) spacecraft orbits Centauri system, conducts investigations, and relays data to Earth. The total time to reach the Centauri system, taking into consideration acceleration and deceleration, will be approximately 50 years.

Computer models of the spacecraft wake

NASA Technical Reports Server (NTRS)

Rubin, A. G.; Heinemann, M.; Tautz, M.; Cooke, D.

1986-01-01

Until recently, computations of space plasma flow over a spacecraft have been unstable for ratios of spacecraft dimension to Debye length typical of the low Earth orbit environment. Calculations are presented of the spacecraft/environment interaction based on two computer codes, MACH and POLAR. MACH, an inside-out particle tracking code, was developed for the purpose of validating the physics of POLAR in regimes where these are no comprehensive theoretical or experimental results. While the spacecraft which can be treated by MACH are restricted to simple geometries, the methodology is more fundamental than POLAR. MACH generates self-consistent solutions within the context of quasisteady Vlasov plasma flow and achieves Debye ratios previously unobtainable. POLAR uses a three-dimensional finite-element representation of the vehicle in a staggered mesh. The plasma sheath is modeled by outside-in particle tracking. Solutions for the plasma flow, wake and vehicle charging are obtained by Vlasov-Poisson iteration; charge stabilization techniques make the results virtually insensitive to the Debye ratio. POLAR reproduces the Laframboise static plasma solutions for sperical probes and fits the Makita-Kuriki probe data for spheres in a flowing plasma in regions where comparisons are valid. POLAR and MACH solutions for the particle and electrostatic potential structure of the wake of a charged disk in a low-altitude flow are shown for Mach numbers 4, 5, and 8. New features of the solutions include ion focussing in the wake and a definitive determination of the sheath edge in the wake which shows that the sheath is not an equipotential.

Measuring the spacecraft and environmental interactions of the 8-cm mercury ion thrusters on the P80-1 mission

NASA Technical Reports Server (NTRS)

Power, J. L.

1981-01-01

The subject interface measurements are described for the Ion Auxiliary Propulsion System (IAPS) flight test of two 8-cm thrusters. The diagnostic devices and the effects to be measured include: 1) quartz crystal microbalances to detect nonvolatile deposition due to thruster operation; 2) warm and cold solar cell monitors for nonvolatile and volatile (mercury) deposition; 3) retarding potential ion collectors to characterize the low energy thruster ionic efflux; and 4) a probe to measure the spacecraft potential and thruster generated electron currents to biased spacecraft surfaces. The diagnostics will also assess space environmental interactions of the spacecraft and thrusters. The diagnostic data will characterize mercury thruster interfaces and provide data useful for future applications.

HERA: an atmospheric probe to unveil the depths of Saturn

NASA Astrophysics Data System (ADS)

Mousis, Olivier; Atkinson, David H.; Amato, Michael; Aslam, Shahid; Atreya, Sushil K.; Blanc, Michel; Bolton, Scott J.; Brugger, Bastien; Calcutt, Simon; Cavalié, Thibault; Charnoz, Sébastien; Coustenis, Athena; DELEUIL, Magali; Ferri, Francesca; Fletcher, Leigh N.; Guillot, Tristan; Hartogh, Paul; Holland, Andrew; Hueso, Ricardo; Keller, Christoph; Kessler, Ernst; Lebreton, Jean-Pierre; leese, Mark; Lellouch, Emmanuel; Levacher, Patrick; Marty, Bernard; Morse, Andrew; Nixon, Conor; Reh, Kim R.; Renard, Jean-Baptiste; Sanchez-Lavega, Agustin; Schmider, François-Xavier; Sheridan, Simon; Simon, Amy A.; Snik, Frans; Spilker, Thomas R.; Stam, Daphne M.; Venkatapathy, Ethiraj; Vernazza, Pierre; Waite, J. Hunter; Wurz, Peter

2016-10-01

The Hera Saturn entry probe mission is proposed as an M-class mission led by ESA with a significant collaboration with NASA. It consists of a Saturn atmospheric probe and a Carrier-Relay spacecraft. Hera will perform in situ measurements of the chemical and isotopic compositions as well as the dynamics of Saturn's atmosphere, with the goal of improving our understanding of the origin, formation, and evolution of Saturn, the giant planets and their satellite systems, with extrapolation to extrasolar planets.The primary science objectives will be addressed by an atmospheric entry probe that would descend under parachute and carry out in situ measurements beginning in the stratosphere to help characterize the location and properties of the tropopause, and continue into the troposphere to pressures of at least 10 bars. All of the science objectives, except for the abundance of oxygen, which may be only addressed indirectly via observations of species whose abundances are tied to the abundance of water, can be achieved by reaching 10 bars. As in previous highly successful collaborative efforts between ESA and NASA, the proposed mission has a baseline concept based on a NASA-provided carrier/data relay spacecraft that would deliver the ESA-provided atmospheric probe to the desired atmospheric entry point at Saturn. ESA's proposed contribution should fit well into the M5 Cosmic Vision ESA call cost envelope.A nominal mission configuration would consist of a probe that detaches from the carrier one to several months prior to probe entry. Subsequent to probe release, the carrier trajectory would be deflected to optimize the over-flight phasing of the probe descent location for both probe data relay as well as performing carrier approach and flyby science, and would allow multiple retransmissions of the probe data for redundancy. The Saturn atmospheric entry probe would in many respects resemble the Jupiter Galileo probe. It is anticipated that the probe architecture for this mission would be battery-powered and accommodate a data relay to the carrier for data collection, storage on board the carrier/data relay, for later retransmission to Earth.

OxfordGrid: a web interface for pairwise comparative map views.

PubMed

Yang, Hongyu; Gingle, Alan R

2005-12-01

OxfordGrid is a web application and database schema for storing and interactively displaying genetic map data in a comparative, dot-plot, fashion. Its display is composed of a matrix of cells, each representing a pairwise comparison of mapped probe data for two linkage groups or chromosomes. These are arranged along the axes with one forming grid columns and the other grid rows with the degree and pattern of synteny/colinearity between the two linkage groups manifested in the cell's dot density and structure. A mouse click over the selected grid cell launches an image map-based display for the selected cell. Both individual and linear groups of mapped probes can be selected and displayed. Also, configurable links can be used to access other web resources for mapped probe information. OxfordGrid is implemented in C#/ASP.NET and the package, including MySQL schema creation scripts, is available at ftp://cggc.agtec.uga.edu/OxfordGrid/.

DC Electric Field Measurement by the Double Probe System Aboard Geotail and its Simulation

NASA Astrophysics Data System (ADS)

Kasaba, Y.; Hayakawa, H.; Ishisaka, K.; Okada, T.; Matsuoka, A.; Mukai, T.; Okada, M.

2005-12-01

We summarize the characteristics of the DC electric field measurement by the double probe system, PANT and EFD-P, aboard Geotail. The accuracy and correction factors for the gain (effective length) and off-set, which depends on ambient plasma conditions, are provided. Accurate measurements of electric fields are essential for space plasma studies, for example, plasma convection, wave-particle interactions, violation of MHD approximation, etc. One typical measurement techniques is the 'Double Probe method', identical to that of a voltmeter: the potential difference between two top-hat probes [cf. Pedersen et al., 1984]. This method can measure electric fields passively and continuously in all plasma conditions. However, the accuracy of the measured electric field values is limited. The probe measurement is also subjected to the variable gain (effective length) of the probe antenna and the artificial offset of the measured values. Those depend on a) the disturbance from ambient plasma and b) the disturbance from the spacecraft and the probe itself. In this paper, we show the results of the characteristics of DC electric field measurement by the PANT probe and the EFD-P (Electric Field Detector - Probe technique) receiver aboard Geotail [Tsuruda et al., 1994], in order to evaluate the accuracy, gain, and offset controlled by ambient plasmas. We conclude that the Geotail electric field measurement by the double probe system has the accuracy 0.4 mV/m for Ex and 0.3 mV/m for Ey, after the correction of the gain and offset. In better conditions, accuracy of Ey is 0.2 mV/m. The potential accuracy would be better because those values are limited by the accuracy of the particle measurement especially in low density conditions. In practical use, the corrections by long-term variation and spacecraft potential are effective to refine the electric field data. The characteristics of long-term variation and the dependences on ambient plasma are not fully understood well, yet. Further works will be needed based on the calibrated LEP data after 1998. It will also cover the conditions rejected in this paper, i.e., low density regions, potential controlled period, electric field quasi-parallel to magnetic field, etc. The comparison with EFD-B (EFD - Beam technique) data will also be included in order to reject the ambiguity in particle observations. In addition, we are trying to establish the numerical model of the double probe system for the full-quantitative understanding of the effect of potential structure and photoelectron distributions. Those will be the basis for planned experiments, BepiColombo to Mercury, ERG to the inner magnetosphere, and the multi-spacecraft magnetospheric mission SCOPE.

KSC-03PD-2741

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment, including setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

KSC-03PD-2740

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment, including setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

KSC-03PD-2739

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. Workers in the spacecraft processing facility on North Vandenberg Air Force Base get ready to begin processing the Gravity Probe B experiment, including setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

Lunar Global Heat Flow Mapping with a Reusable Lander Deployed from the Deep Space Gateway Spacecraft

NASA Astrophysics Data System (ADS)

Nagihara, S.; Zacny, K.; Chu, P.; Kiefer, W. S.

2018-02-01

We propose to equip the Deep Space Gateway spacecraft with a reusable lander that can shuttle to and from the lunar surface, and use it for collecting heat flow measurements globally on the lunar surface.

Control Algorithms Charge Batteries Faster

NASA Technical Reports Server (NTRS)

2012-01-01

On March 29, 2011, NASA s Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) spacecraft beamed a milestone image to Earth: the first photo of Mercury taken from orbit around the solar system s innermost planet. (MESSENGER is also the first spacecraft to orbit Mercury.) Like most of NASA s deep space probes, MESSENGER is enabled by a complex power system that allows its science instruments and communications to function continuously as it travels millions of miles from Earth. "Typically, there isn't one particular power source that can support the entire mission," says Linda Taylor, electrical engineer in Glenn Research Center s Power Systems Analysis Branch. "If you have solar arrays and you are in orbit, at some point you re going to be in eclipse." Because of this, Taylor explains, spacecraft like MESSENGER feature hybrid power systems. MESSENGER is powered by a two-panel solar array coupled with a nickel hydrogen battery. The solar arrays provide energy to the probe and charge the battery; when the spacecraft s orbit carries it behind Mercury and out of the Sun s light, the spacecraft switches to battery power to continue operations. Typically, hybrid systems with multiple power inputs and a battery acting alternately as storage and a power source require multiple converters to handle the power flow between the devices, Taylor says. (Power converters change the qualities of electrical energy, such as from alternating current to direct current, or between different levels of voltage or frequency.) This contributes to a pair of major concerns for spacecraft design. "Weight and size are big drivers for any space application," Taylor says, noting that every pound added to a space vehicle incurs significant costs. For an innovative solution to managing power flows in a lightweight, cost-effective manner, NASA turned to a private industry partner.

An Overview of the Mars Reconnaissance Orbiter (MRO) Science Mission

NASA Technical Reports Server (NTRS)

Zurek, Richard W.; Smrekar, Suzanne E.

2007-01-01

The Mars Reconnaissance Orbiter (MRO) is the latest addition to the suite of missions on or orbiting Mars as part of the NASA Mars Exploration Program. Launched on 12 August 2005, the orbiter successfully entered Mars orbit on 10 March 2006 and finished aerobraking on 30 August 2006. Now in its near-polar, near-circular, low-altitude (approximately 300 km), 3 p.m. orbit, the spacecraft is operating its payload of six scientific instruments throughout a one-Mars-year Primary Science Phase (PSP) of global mapping, regional survey, and targeted observations. Eight scientific investigations were chosen for MRO, two of which use either the spacecraft accelerometers or tracking of the spacecraft telecom signal to acquire data needed for analysis. Six instruments, including three imaging systems, a visible-near infrared spectrometer, a shallow-probing subsurface radar, and a thermal-infrared profiler, were selected to complement and extend the capabilities of current working spacecraft at Mars. Whether observing the atmosphere, surface, or subsurface, the MRO instruments are designed to achieve significantly higher resolution while maintaining coverage comparable to the current best observations. The requirements to return higher-resolution data, to target routinely from a low-altitude orbit, and to operate a complex suite of instruments were major challenges successfully met in the design and build of the spacecraft, as well as by the mission design. Calibration activities during the seven-month cruise to Mars and limited payload operations during a three-day checkout prior to the start of aerobraking demonstrated, where possible, that the spacecraft and payload still had the functions critical to the science mission. Two critical events, the deployment of the SHARAD radar antenna and the opening of the CRISM telescope cover, were successfully accomplished in September 2006. Normal data collection began 7 November 2006 after solar conjunction. As part of its science mission, MRO will also aid identification and characterization of the most promising sites for future landed missions, both in terms of safety and in terms of the scientific potential for future discovery. Ultimately, MRO data will advance our understanding of how Mars has evolved and by which processes that change occurs, all within a framework of identifying the presence, extent, and role of water in shaping the planet s climate over time.

Vertical structure of the near-surface expanding ionosphere of comet 67P probed by Rosetta

NASA Astrophysics Data System (ADS)

Heritier, K. L.; Henri, P.; Vallières, X.; Galand, M.; Odelstad, E.; Eriksson, A. I.; Johansson, F. L.; Altwegg, K.; Behar, E.; Beth, A.; Broiles, T. W.; Burch, J. L.; Carr, C. M.; Cupido, E.; Nilsson, H.; Rubin, M.; Vigren, E.

2017-07-01

The plasma environment has been measured for the first time near the surface of a comet. This unique data set has been acquired at 67P/Churyumov-Gerasimenko during ESA/Rosetta spacecraft's final descent on 2016 September 30. The heliocentric distance was 3.8 au and the comet was weakly outgassing. Electron density was continuously measured with Rosetta Plasma Consortium (RPC)-Mutual Impedance Probe (MIP) and RPC-LAngmuir Probe (LAP) during the descent from a cometocentric distance of 20 km down to the surface. Data set from both instruments have been cross-calibrated for redundancy and accuracy. To analyse this data set, we have developed a model driven by Rosetta Orbiter Spectrometer for Ion and Neutral Analysis-COmetary Pressure Sensor total neutral density. The two ionization sources considered are solar extreme ultraviolet radiation and energetic electrons. The latter are estimated from the RPC-Ion and Electron Sensor (IES) and corrected for the spacecraft potential probed by RPC-LAP. We have compared the results of the model to the electron densities measured by RPC-MIP and RPC-LAP at the location of the spacecraft. We find good agreement between observed and modelled electron densities. The energetic electrons have access to the surface of the nucleus and contribute as the main ionization source. As predicted, the measurements exhibit a peak in the ionospheric density close to the surface. The location and magnitude of the peak are estimated analytically. The measured ionospheric densities cannot be explained with a constant outflow velocity model. The use of a neutral model with an expanding outflow is critical to explain the plasma observations.

Theoretical analysis of a dual-probe scanning tunneling microscope setup on graphene.

PubMed

Settnes, Mikkel; Power, Stephen R; Petersen, Dirch H; Jauho, Antti-Pekka

2014-03-07

Experimental advances allow for the inclusion of multiple probes to measure the transport properties of a sample surface. We develop a theory of dual-probe scanning tunneling microscopy using a Green's function formalism, and apply it to graphene. Sampling the local conduction properties at finite length scales yields real space conductance maps which show anisotropy for pristine graphene systems and quantum interference effects in the presence of isolated impurities. Spectral signatures in the Fourier transforms of real space conductance maps include characteristics that can be related to different scattering processes. We compute the conductance maps of graphene systems with different edge geometries or height fluctuations to determine the effects of nonideal graphene samples on dual-probe measurements.

A new method for mapping the three-dimensional atomic distribution within nanoparticles by atom probe tomography (APT).

PubMed

Kim, Se-Ho; Kang, Phil Woong; Park, O Ok; Seol, Jae-Bok; Ahn, Jae-Pyoung; Lee, Ji Yeong; Choi, Pyuck-Pa

2018-07-01

We present a new method of preparing needle-shaped specimens for atom probe tomography from freestanding Pd and C-supported Pt nanoparticles. The method consists of two steps, namely electrophoresis of nanoparticles on a flat Cu substrate followed by electrodeposition of a Ni film acting as an embedding matrix for the nanoparticles. Atom probe specimen preparation can be subsequently carried out by means of focused-ion-beam milling. Using this approach, we have been able to perform correlative atom probe tomography and transmission electron microscopy analyses on both nanoparticle systems. Reliable mass spectra and three-dimensional atom maps could be obtained for Pd nanoparticle specimens. In contrast, atom probe samples prepared from C-supported Pt nanoparticles showed uneven field evaporation and hence artifacts in the reconstructed atom maps. Our developed method is a viable means of mapping the three-dimensional atomic distribution within nanoparticles and is expected to contribute to an improved understanding of the structure-composition-property relationships of various nanoparticle systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Titan Touchdown

NASA Image and Video Library

2017-01-11

On Jan. 14, 2005, ESA's Huygens probe made its descent to the surface of Saturn's hazy moon, Titan. Carried to Saturn by NASA's Cassini spacecraft, Huygens made the most distant landing ever on another world, and the only landing on a body in the outer solar system. This video uses actual images taken by the probe during its two-and-a-half hour fall under its parachutes. Also include mission animation.

KSC-06pd2788

NASA Image and Video Library

2006-12-11

KENNEDY SPACE CENTER, FLA. -- Workers at Astrotech Space Operations in Titusville, Fla., wipe down the crates containing the probes of the THEMIS spacecraft. THEMIS, which stands for Time History of Events and Macroscale Interactions during Substorms, comprises five identical probes that will study the dynamic and colorful eruptions of auroras. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

KSC-06pd2787

NASA Image and Video Library

2006-12-11

KENNEDY SPACE CENTER, FLA. -- Workers at Astrotech Space Operations in Titusville, Fla., wipe down the crates containing the probes of the THEMIS spacecraft. THEMIS, which stands for Time History of Events and Macroscale Interactions during Substorms, comprises five identical probes that will study the dynamic and colorful eruptions of auroras. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

Ultra-Stable Oscillators for Probe Radio Science Investigations

NASA Technical Reports Server (NTRS)

Asmar, Sami

2012-01-01

An Ultra-Stable Oscillator (USO) is: A frequency reference, and A clock It is stable, small, and sensitive. It is a science and an art form. It is flown on spacecraft/probes. It]is utilized at ground stations alone or as a cleanup loop. It eliminates lock-up time on uplink for occultation egress & effect of media on uplink signal. It has enabled significant planetary science investigations.

Planetary quarantine

NASA Technical Reports Server (NTRS)

1977-01-01

Those areas of future missions which will be impacted by planetary quarantine (PQ) constraints were identified. The specific objectives for this reporting period were (1) to perform an analysis of the effects of PQ on an outer planet atmospheric probe, and (2) to prepare a quantitative illustration of spacecraft microbial reduction resulting from exposure to space environments. The Jupiter Orbiter Probe mission was used as a model for both of these efforts.

Wire Probe Antenna (WPT) and Electric Field Detector (EFD0 of Plasma Wave Experiment (PWE) aboard ARASE: Specifications and Evaluation results

NASA Astrophysics Data System (ADS)

Matsuda, S.; Kasaba, Y.; Ishisaka, K.; Kasahara, Y.; Imachi, T.; Yagitani, S.; Kojima, H.; Kurita, S.; Shoji, M.; Hori, T.; Shinbori, A.; Teramoto, M.; Miyoshi, Y.; Nakagawa, T.; Takahashi, N.; Nishimura, Y.; Matsuoka, A.; Tsuchiya, F.; Kumamoto, A.; Nomura, R.

2017-12-01

This paper summarizes the specifications and the evaluation results of Wire Probe Antenna (WPT) and Electric Field Detector (EFD), which are the key parts of Plasma Wave Experiment (PWE) aboard the Arase satellite, in their initial operations and the beginning phase of the full observations. WPT consists of the two dipole antennas as electric field sensors with 32m tip-to-tip length, with a sphere probe (6 cm diameter) attached at each end of wires (length: 15-m). They are extended orthogonally in the spin plane which is roughly perpendicular to the Sun. It enables the PWE to measure the E-field from DC to 10 MHz. This system is almost compatible to the WPT of the Plasma Wave Investigation (PWI) aboard BepiColombo Mercury Magnetospheric Orbiter, except the material of the spherical probe (ERG: Aluminium alloy, MMO: Titanium-alloy). This paper shows the extended length evaluated by the Lorentz force (spacecraft velocity x B-field) and the antenna impedance as the basic information of the E-field measurement capability of the PWE E-field receivers, with the evaluation for the possible degradation of the probe surface coated by TiAlN as BepiColombo. EFD is the 2-channel low frequency electric receiver as a part of EWO (EFD/WFC/OFA), for the measurement of 2ch electric field in the spin-plane with the sampling rate of 512 Hz (dynamic range: +-200 mV/m, +-3 V/m) and the 4ch spacecraft potential with the sampling rate of 128 Hz (dynamic range: +-100 V), respectively, with the bias control capability fed to the WPT probes. The electric field in DC - 232Hz provides the capability to detect (1) the fundamental information of the plasma dynamics and accelerations and (2) the characteristics of MHD and ion waves with their Poynting vectors with the data measured by MGF and PWE/WFC-B connected to PWE/SCM. The spacecraft potential provides the electron density information with UHR frequency. This paper also introduces the data sets and their calibration status.

Contingency maneuver strategies for the Total Ozone Mapping Spectrometer-Earth Probe (TOMS-EP)

NASA Technical Reports Server (NTRS)

Kestler, James; Walls, Donna

1995-01-01

The Total Ozone Mapping Spectrometer-Earth Probe (TOMS-EP) is a polar-orbiting spacecraft designed to measure total ozone levels in the Earth's atmosphere. The nominal mission orbit is a 955-kilometer circular Sun-synchronous orbit with an ascending node mean local crossing time (MLT) between 11:02 a.m. and 11:25 a.m. These two mean local ascending node times constitute the boundaries of the MLT box for this mission. The MLT boundaries were chosen to maintain the Sun-to-Earth-to-vehicle orbit-normal (SVN) angle within a preselected set of seasonally independent boundaries. Because the SVN angle is seasonally dependent, but the MLT is not, contingency options for correcting the MLT of orbital states that fall outside of the required MLT range become time dependent. This paper focuses on contingency orbit adjustment strategies developed at the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) during the mission planning phase of TOMS-EP. Time-dependent delta-V strategies are presented for correcting mission orbit states lying outside of the MLT range. Typically, passive control of the MLT drift rate can be used to restore the orbit state to the required MLT before a seasonal violation of SVN angle constraints can occur. Passive control of the MLT drift rate is obtained through adjustment of the semimajor axis and/or the inclination. The time between initial arrival on orbit at an 'out-of-the box' MLT state and violation of the SVN angle constraints is always less than or equal to 1 year. The choice of which parameter(s) to adjust is dictated by the duration of this time period, the desired mission lifetime, the delta-V cost, and operational constraints.

NASA Tech Briefs, August 2012

NASA Technical Reports Server (NTRS)

2012-01-01

Topics covered include: Mars Science Laboratory Drill; Ultra-Compact Motor Controller; A Reversible Thermally Driven Pump for Use in a Sub-Kelvin Magnetic Refrigerator; Shape Memory Composite Hybrid Hinge; Binding Causes of Printed Wiring Assemblies with Card-Loks; Coring Sample Acquisition Tool; Joining and Assembly of Bulk Metallic Glass Composites Through Capacitive Discharge; 670-GHz Schottky Diode-Based Subharmonic Mixer with CPW Circuits and 70-GHz IF; Self-Nulling Lock-in Detection Electronics for Capacitance Probe Electrometer; Discontinuous Mode Power Supply; Optimal Dynamic Sub-Threshold Technique for Extreme Low Power Consumption for VLSI; Hardware for Accelerating N-Modular Redundant Systems for High-Reliability Computing; Blocking Filters with Enhanced Throughput for X-Ray Microcalorimetry; High-Thermal-Conductivity Fabrics; Imidazolium-Based Polymeric Materials as Alkaline Anion-Exchange Fuel Cell Membranes; Electrospun Nanofiber Coating of Fiber Materials: A Composite Toughening Approach; Experimental Modeling of Sterilization Effects for Atmospheric Entry Heating on Microorganisms; Saliva Preservative for Diagnostic Purposes; Hands-Free Transcranial Color Doppler Probe; Aerosol and Surface Parameter Retrievals for a Multi-Angle, Multiband Spectrometer LogScope; TraceContract; AIRS Maps from Space Processing Software; POSTMAN: Point of Sail Tacking for Maritime Autonomous Navigation; Space Operations Learning Center; OVERSMART Reporting Tool for Flow Computations Over Large Grid Systems; Large Eddy Simulation (LES) of Particle-Laden Temporal Mixing Layers; Projection of Stabilized Aerial Imagery Onto Digital Elevation Maps for Geo-Rectified and Jitter-Free Viewing; Iterative Transform Phase Diversity: An Image-Based Object and Wavefront Recovery; 3D Drop Size Distribution Extrapolation Algorithm Using a Single Disdrometer; Social Networking Adapted for Distributed Scientific Collaboration; General Methodology for Designing Spacecraft Trajectories; Hemispherical Field-of-View Above-Water Surface Imager for Submarines; and Quantum-Well Infrared Photodetector (QWIP) Focal Plane Assembly.

Voyage to Jupiter

NASA Technical Reports Server (NTRS)

Morrison, D.; Samz, J.

1980-01-01

Early observations of the Jovian system are reviewed as well as the scientific objectives of the Pioneer and Voyager flyby missions. Launch vehicles, spacecraft trajectories, and the instruments carried are described. Photographs obtained by both voyage spacecraft are presented along with day-by-day summaries of the findings recorded by the various instruments and experiments carried by each spacecraft. Pictorial maps of the Galilean satellites, and lists of the Voyager science and managements teams are included.

Artist Rendering of NASA Dawn Spacecraft Approaching Mars

NASA Image and Video Library

2009-05-23

Artist rendering of NASA's Dawn spacecraft approaching Mars. Dawn, part of NASA's Discovery Program of competitively selected missions, was launched in 2007 to orbit the large asteroid Vesta and the dwarf planet Ceres. The two bodies have very different properties from each other. By observing them both with the same set of instruments, Dawn will probe the early solar system and specify the properties of each body. http://photojournal.jpl.nasa.gov/catalog/PIA18152

Geologic Exploration of the Planets: The First 50 Years

NASA Astrophysics Data System (ADS)

Carr, Michael H.

2013-01-01

Fifty years ago, on 14 December 1962, the Mariner 2 spacecraft flew by Venus and inaugurated the modern era of planetary exploration. Since that first Venus flyby, roughly 80 spacecraft have successfully probed, orbited, flown by, landed on, or roved on other planets, satellites, asteroids, and comets. As Carl Sagan used to say, only one generation of humankind can be the first explorers of the solar system, and we are that generation.

Teaching old spacecraft new tricks

NASA Technical Reports Server (NTRS)

Farquhar, Robert; Dunham, David

1988-01-01

The technique of sending existing space probes on extended mission by altering their orbital paths with gravity-assist maneuvers and relatively brief rocket firings is examined. The use of the technique to convert the International Sun-Earth Explorer 3 mission into the International Cometary Explorer mission is discussed. Other examples are considered, including the extension of the Giotto mission and the retargeting of the Sakigake spacecraft. The original and altered trajectories of these three missions are illustrated.

Modeling and simulations of the double-probe electric field instrument in tenuous and cold streaming plasmas

NASA Astrophysics Data System (ADS)

Miyake, Y.; Cully, C. M.; Usui, H.; Nakashima, H.

2013-12-01

In order to increase accuracy and reliability of in-situ measurements made by scientific spacecraft, it is imperative to develop comprehensive understanding of spacecraft-plasma interactions. In space environments, not only the spacecraft charging but also surrounding plasma disturbances such as caused by the wake formation may interfere directly with in-situ measurements. The self-consistent solutions of such phenomena are necessary to assess their effects on scientific spacecraft systems. As our recent activity, we work on the modeling and simulations of Cluster double-probe instrument in tenuous and cold streaming plasmas [1]. Double-probe electric field sensors are often deployed using wire booms with radii much less than typical Debye lengths of magnetospheric plasmas (millimeters compared to tens of meters). However, in tenuous and cold streaming plasmas seen in the polar cap and lobe regions, the wire booms have a high positive potential due to photoelectron emission and can strongly scatter approaching ions. Consequently, an electrostatic wake formed behind the spacecraft is further enhanced by the presence of the wire booms. We reproduce this process for the case of the Cluster satellite by performing plasma particle-in-cell (PIC) simulations [2], which include the effects of both the spacecraft body and the wire booms in a simultaneous manner, on modern supercomputers. The simulations reveal that the effective thickness of the booms for the Cluster Electric Field and Wave (EFW) instrument is magnified from its real thickness (2.2 millimeters) to several meters, when the spacecraft potential is at 30-40 volts. Such booms enhance the wake electric field magnitude by a factor of about 2 depending on the spacecraft potential, and play a principal role in explaining the in situ Cluster EFW data showing sinusoidal spurious electric fields of about 10 mV/m amplitudes. The boom effects are quantified by comparing PIC simulations with and without wire booms. The paper also reports some recent progress of ongoing PIC simulation research that focuses on spurious electric field generation in subsonic ion flows. Our preliminary simulation results revealed that; (1) there is no apparent wake signature behind the spacecraft in such a condition, but (2) spurious electric field over 1 mV/m amplitude is observed in the direction of the flow vector. The observed field amplitude is sometimes comparable to the convection electric field (a few mV/m) associated with the flow. Our analysis also confirmed that the spurious field is caused by a weakly-asymmetric potential pattern created by the ion flow. We will present the parametric study of such spurious fields for various conditions of plasma flows. [References] [1] Miyake, Y., C. M. Cully, H. Usui, and H. Nakashima (2013), Plasma particle simulations of wake formation behind a spacecraft with thin wire booms, submitted to J. Geophys. Res. [2] Miyake, Y., and H. Usui (2009), New electromagnetic particle simulation code for the analysis of spacecraft-plasma interactions, Phys. Plasmas, 16, 062904, doi:10.1063/1.3147922.

Mapping the Heliosphere

NASA Image and Video Library

2011-04-28

Data from NASA Cassini spacecraft have enabled scientists to create this map of the heliosphere, the bubble of charged particles around our sun. Charged particles stream out from our sun in a phenomenon known as solar wind.

Studying the energy variation in the powered Swing-By in the Sun-Mercury system

NASA Astrophysics Data System (ADS)

Ferreira, A. F. S.; Prado, A. F. B. A.; Winter, O. C.; Santos, D. P. S.

2017-10-01

A maneuver where a spacecraft passes close to Mercury and uses the gravity of this body combined with an impulse applied at the periapsis, with different magnitudes and directions, is presented. The main objective of this maneuver is the fuel economy in space missions. Using this maneuver, it is possible to insert the spacecraft into an orbit captured around the Sun or Mercury. Trajectories escaping the Solar System are also obtained and mapped. Maps of the spacecraft energy variation relative to the Sun and the types of orbits resulting from the maneuver are presented, based in numerical integrations. The results show that applying the impulse out of the direction of motion can optimize the maneuver due to the effect of the combination of the impulse and the gravity.

KSC-97PC1393

NASA Image and Video Library

1997-09-10

Pieces of the Huygens probe internal insulating foam await inspection after removal from the probe in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Internal inspection, insulation repair and a cleaning of the probe were required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle at Launch Pad 40 at Cape Canaveral Air Station

Mapping the Galilean satellites of Jupiter with Voyager data.

USGS Publications Warehouse

Batson, R.M.

1980-01-01

The four Galilean satellites of Jupiter are being mapped using image data from the Voyager 1 and 2 spacecraft. The maps are published at several scales and in several versions. Preliminary maps at 1:25,000,000-required for mission planning and preliminary science reports-were compiled within three weeks of data acquisition and have been published. Later maps incorporate Rand Corporation photogrammetric triangulations. - from Authors

Amateur Radio Communications with a Deep Space Probe (Yes, It's Possible)

NASA Astrophysics Data System (ADS)

Cudnik, Brian; Rahman, Mahmudur; Saganti, Seth; Erickson, Gary M.; Saganti, Premkumar

2015-05-01

Prairie View A&M University through the collaboration with NASA-Johnson Space Center has partnered with the Kyushu Institute of Technology (KIT), Japan and developed a payload for the Shinen-2 spacecraft that was launched from Japan on December 3, 2014 as part of the Hayabusa2 mission. The main purpose of the Shinen-2 spacecraft is deep space communication experiment to test the feasibility of deep-space radio communications from the spacecraft to Earth without the need of the Deep Space Network (DSN) of NASA. This presents an opportunity to the wider community of amateur astronomers, ham radio operators, and other research personnel in that they will have the opportunity to work with deep space communication such as Shinen-2 spacecraft. It should be possible to detect a signal as an increased strength from Shinen-2 spacecraft at a rest frequency of 437.385 MHz, using commercially available equipment procured at low-cost, when the spacecraft approaches to within 3,000,000 km of the Earth during December 2015.

Nonlinear Dynamic Behavior in the Cassini Spacecraft Modal Survey

NASA Technical Reports Server (NTRS)

Carney, Kelly S.

1997-01-01

In October 1997, the 6-ton robotic spacecraft, Cassini, will lift off from Cape Canaveral atop a Titan IV B rocket, beginning a 7-year journey to Saturn. Upon completion of that voyage, Cassini will send the Huygens probe into the atmosphere of Saturn's largest moon, Titan. Cassini will then spend years studying Saturn's vast realm of rings, icy moons, and magnetic fields. The size and complexity of this endeavor mandates the involvement of many organizations. The Jet Propulsion Laboratory (JPL) manages the project for NASA and is responsible for the spacecraft design, development, and assembly. The NASA Lewis Research Center is the launch system integrator. As is typical for such a spacecraft, a test-verified finite element model is required for loads analysis. JPL had responsibility for the Cassini modal survey and the development of the spacecraft test-verified finite element model. Test verification is a complex and sometimes subjective process. Because of this, NASA Lewis independently verified and validated the Cassini spacecraft modal survey.

NASA Tech Briefs, November 2006

NASA Technical Reports Server (NTRS)

2006-01-01

Topics include: Simulator for Testing Spacecraft Separation Devices; Apparatus for Hot Impact Testing of Material Specimens; Instrument for Aircraft-Icing and Cloud-Physics Measurements; Advances in Measurement of Skin Friction in Airflow; Improved Apparatus for Testing Monoball Bearings; High-Speed Laser Scanner Maps a Surface in Three Dimensions; Electro-Optical Imaging Fourier-Transform Spectrometer; Infrared Instrument for Detecting Hydrogen Fires; Modified Coaxial Probe Feeds for Layered Antennas; Detecting Negative Obstacles by Use of Radar; Cryogenic Pound Circuits for Cryogenic Sapphire Oscillators; PixelLearn; New Software for Predicting Charging of Spacecraft; Conversion Between Osculating and Mean Orbital Elements; Generating a 2D Representation of a Complex Data Structure; Making Activated Carbon by Wet Pressurized Pyrolysis; Composite Solid Electrolyte Containing Li+- Conducting Fibers; Electrically Conductive Anodized Aluminum Surfaces; Rapid-Chill Cryogenic Coaxial Direct-Acting Solenoid Valve; Variable-Tension-Cord Suspension/Vibration- Isolation System; Techniques for Connecting Superconducting Thin Films; Versatile Friction Stir Welding/Friction Plug Welding System; Thermal Spore Exposure Vessels; Enumerating Spore-Forming Bacteria Airborne with Particles; Miniature Oxidizer Ionizer for a Fuel Cell; Miniature Ion-Array Spectrometer; Promoted-Combustion Chamber with Induction Heating Coil; Miniature Ion-Mobility Spectrometer; Mixed-Salt/Ester Electrolytes for Low-Temperature Li+ Cells; Miniature Free-Space Electrostatic Ion Thrusters; Miniature Bipolar Electrostatic Ion Thruster; Holographic Plossl Retroreflectors; Miniature Electrostatic Ion Thruster With Magnet; Using Apex To Construct CPM-GOMS Models; Sequence Detection for PPM Optical Communication With ISI; Algorithm for Rapid Searching Among Star-Catalog Entries; Expectation-Based Control of Noise and Chaos; Radio Heating of Lunar Soil to Release Gases; Using Electrostriction to Manipulate Ullage in Microgravity; Equations for Scoring Rules When Data Are Missing; Insulating Material for Next-Generation Spacecraft; and Pseudorandom Switching for Adding Radar to the AFF Sensor.

Tracking a Solar Wind Dynamic Pressure Pulses' Impact Through the Magnetosphere Using the Heliophysics System Observatory

NASA Astrophysics Data System (ADS)

Vidal-Luengo, S.; Moldwin, M.

2017-12-01

During northward Interplanetary Magnetic Field (IMF) Bz conditions, the magnetosphere acts as a closed "cavity" and reacts to solar wind dynamic pressure pulses more simply than during southward IMF conditions. Effects of solar wind dynamic pressure have been observed as geomagnetic lobe compressions depending on the characteristics of the pressure pulse and the spacecraft location. One of the most important aspects of this study is the incorporation of simultaneous observations by different missions, such as WIND, CLUSTER, THEMIS, MMS, Van Allen Probes and GOES as well as magnetometer ground stations that allow us to map the magnetosphere response at different locations during the propagation of a pressure pulse. In this study we used the SYM-H as an indicator of dynamic pressure pulses occurrence from 2007 to 2016. The selection criteria for events are: (1) the increase in the index must be bigger than 10 [nT] and (2) the rise time must be in less than 5 minutes. Additionally, the events must occur under northward IMF and at the same time at least one spacecraft has to be located in the magnetosphere nightside. Using this methodology we found 66 pressure pulse events for analysis. Most of them can be classified as step function pressure pulses or as sudden impulses (increase followed immediately by a decrease of the dynamic pressure). Under these two categories the results show some systematic signatures depending of the location of the spacecraft. For both kind of pressure pulse signatures, compressions are observed on the dayside. However, on the nightside compressions and/or South-then-North magnetic signatures can be observed for step function like pressure pulses, meanwhile for the sudden impulse kind of pressure pulses the magnetospheric response seems to be less global and more dependent on the local conditions.

NASA Tech Briefs, January 2003

NASA Technical Reports Server (NTRS)

2003-01-01

Topics covered include: Optoelectronic Tool Adds Scale Marks to Photographic Images; Compact Interconnection Networks Based on Quantum Dots; Laterally Coupled Quantum-Dot Distributed-Feedback Lasers; Bit-Serial Adder Based on Quantum Dots; Stabilized Fiber-Optic Distribution of Reference Frequency; Delay/Doppler-Mapping GPS-Reflection Remote-Sensing System; Ladar System Identifies Obstacles Partly Hidden by Grass; Survivable Failure Data Recorders for Spacecraft; Fiber-Optic Ammonia Sensors; Silicon Membrane Mirrors with Electrostatic Shape Actuators; Nanoscale Hot-Wire Probes for Boundary-Layer Flows; Theodolite with CCD Camera for Safe Measurement of Laser-Beam Pointing; Efficient Coupling of Lasers to Telescopes with Obscuration; Aligning Three Off-Axis Mirrors with Help of a DOE; Calibrating Laser Gas Measurements by Use of Natural CO2; Laser Ranging Simulation Program; Micro-Ball-Lens Optical Switch Driven by SMA Actuator; Evaluation of Charge Storage and Decay in Spacecraft Insulators; Alkaline Capacitors Based on Nitride Nanoparticles; Low-EC-Content Electrolytes for Low-Temperature Li-Ion Cells; Software for a GPS-Reflection Remote-Sensing System; Software for Building Models of 3D Objects via the Internet; "Virtual Cockpit Window" for a Windowless Aerospacecraft; CLARAty Functional-Layer Software; Java Library for Input and Output of Image Data and Metadata; Software for Estimating Costs of Testing Rocket Engines; Energy-Absorbing, Lightweight Wheels; Viscoelastic Vibration Dampers for Turbomachine Blades; Soft Landing of Spacecraft on Energy-Absorbing Self-Deployable Cushions; Pneumatically Actuated Miniature Peristaltic Vacuum Pumps; Miniature Gas-Turbine Power Generator; Pressure-Sensor Assembly Technique; Wafer-Level Membrane-Transfer Process for Fabricating MEMS; A Reactive-Ion Etch for Patterning Piezoelectric Thin Film; Wavelet-Based Real-Time Diagnosis of Complex Systems; Quantum Search in Hilbert Space; Analytic Method for Computing Instrument Pointing Jitter; and Semiselective Optoelectronic Sensors for Monitoring Microbes.

The Heavy Ion Afternoon Bulge: Structure and Formation Mechanisms

NASA Astrophysics Data System (ADS)

Fernandes, P. A.; Larsen, B.; Skoug, R. M.; Reeves, G. D.; Denton, M.; Engel, M.; Ferradas, C.; Funsten, H. O.; Henderson, M. G.; Jahn, J. M.; Morley, S.; Thomsen, M. F.

2017-12-01

Recent observations of near-equatorial inner magnetosphere plasma composition indicate the presence of an "afternoon bulge" plasma population at low L-shell. A detailed statistical survey using HOPE data characterized this afternoon bulge as an enhancement in 10 keV O+ and He+ ions extending from 1100-2200 MLT and 2 ≤ L ≤ 4 during quiet/moderate geomagnetic activity (Kp < 5). This statistical HOPE study postulated that formation of the bulge is caused by variations in Kp: 10 keV particles have access to low L-shells during geomagnetically active times and become trapped during the transition to quiet times. In this study, we expand on previous observations of the afternoon bulge by examining individual transits of this feature by the Van Allen Probes. We analyze periods with optimal spacecraft transits of the afternoon bulge region, including: May - Oct. 2013, Feb. - June 2014, and Apr. - Aug. 2015. We determine the presence and duration of the bulge during case studies representing three categories of geomagnetic activity: 1) extended quiet geomagnetic conditions; 2) sharp transitions of Kp from active to quiet conditions; and 3) rises and falls in Kp on the time scales of spacecraft orbits to days. We thoroughly characterize the energy structure of the bulge as a function of Kp. We also analyze these transits of the bulge in the context of plasma access using both drift path modeling and UBK-derived energy access maps.

Recovery of evolution of Grad-Shafranov equilibria from single-spacecraft data: Benchmarking and application to a flux transfer event

NASA Astrophysics Data System (ADS)

Sonnerup, B. U.; Hasegawa, H.; Nakamura, T.

2010-12-01

Even after the advent of multi-spacecraft missions such as Cluster and THEMIS, it has been difficult to distinguish between time evolution of, and spatial variation within, a space plasma structure on the basis of in situ measurements. We present a method for analyzing time evolution of two-dimensional (2D) and magnetohydrostatic, namely Grad-Shafranov equilibria, using data recorded by an observing probe as it traverses a quasi-static, 2D magnetic-field/plasma structure. The method recovers spatial initial values used in the classical Grad-Shafranov (GS) reconstruction [Sonnerup et al., JGR, 2006] for an interval before and after the time of actual measurements, by advancing them backward and forward in time based on a set of equation for an incompressible plasma; the consequence is generation of multiple GS maps or a movie of the 2D field structure. The method is successfully benchmarked by use of a 2D magnetohydrodynamic simulation of time-dependent magnetic reconnection, and then is applied to a magnetic flux transfer event (FTE) seen by Cluster at the dayside high-latitude magnetopause, which has been analyzed with the GS method [Hasegawa et al., Ann. Geophys., 2006]. The application shows that the field lines constituting the FTE flux rope were contracting toward its center as a result of modest convective flow in the region around the core of the flux rope.

Measurement of vehicle potential using a mother-daughter tethered rocket

NASA Technical Reports Server (NTRS)

Williamson, P. R.; Denig, W. F.; Banks, P. M.; Raitt, W. J.; Kawashima, N.; Hirao, K.; Oyama, K. I.; Sasaki, S.

1982-01-01

The equipment, experimental design, and results of mother-daughter tethered probes for measuring the potential of a spacecraft are described. The object was to inject a probe into the ionosphere by rocket and then lower an impedance voltage monitor-equipped section of the probe by means of a highly insulated wire. The mother probe, also carrying voltage monitors, would inject charges into the plasma that would be measured at both ends of the tether. Instrumentation on the daughter probe included voltage current monitors and a Langmuir probe, while the mother payload also carried a charge probe, floating probe, a Langmuir probe, and an impedance probe. The first launch was from Japan in 1980, and operations confirmed that Langmuir probes with area ratios less than 400:1 can produce changes in the vehicle potential if probe voltages of more than 10 V are applied in the collection mode. A ratio of 200:1 was sufficient for the daughter probe with voltages of 5 V. The experiment is concluded to verify the tethered probe method of measuring vehicle potential.

Pioneer spacecraft operation at low and high spin rates

NASA Technical Reports Server (NTRS)

1973-01-01

The feasibility of executing major changes upward or downward from the nominal spin rate for which the Pioneer F&G spacecraft was designed was investigated along with the extent of system and subsystem modifications required to implement these mode changes in future spacecraft evolving from the baseline Pioneer F and G. Results of a previous study are re-examined and updated for an extended range of spin rate variations for missions that include outer planet orbiters, outer planet flyby and outer planet probe delivery. However, in the interest of design simplicity and cost economy, major modifications of the baseline Pioneer system and subsystem concept were avoided.

Mariner-Venus 1967

NASA Technical Reports Server (NTRS)

1971-01-01

Detailed information on the spacecraft performance, mission operations, and tracking and data acquisition is presented for the Mariner Venus 1967 and Mariner Venus 1967 extension projects. Scientific and engineering results and conclusions are discussed, and include the scientific mission, encounter with Venus, observations near Earth, and cruise phase of the mission. Flight path analysis, spacecraft subsystems, and mission-related hardware and computer program development are covered. The scientific experiments carried by Mariner 5 were ultraviolet photometer, solar plasma probe, helium magnetometer, trapped radiation detector, S-band radio occultation, dual-frequency radio propagation, and celestial mechanics. The engineering experience gained by converting a space Mariner Mars 1964 spacecraft into one flown to Venus is also described.

Flexible stator control on the Galileo spacecraft

NASA Technical Reports Server (NTRS)

Kopf, E. H.; Brown, T. K.; Marsh, E. L.

1979-01-01

Galileo is a dual-spin spacecraft designed to deliver a probe to Jupiter and then orbit the planet. The stator, or despun section, contains four flexible modes below 10 Hz and the despun actuator is separated from the inertial sensors by this flexibility. Control loop separation by bandwidth proved unacceptable due to performance requirements. To obtain the desired performance, a control scheme was devised which consists of three parts. First, flexibility damping and control notch filtering are accomplished by phase locked loop techniques. Second, slewing maneuvers are produced by torque profiles which are nonexcitatory to the structure. Finally, a low bandwidth perturbation controller is supplied to remove spacecraft disturbances.

Huygens Titan Probe Trajectory Reconstruction Using Traditional Methods and the Program to Optimize Simulated Trajectories II

NASA Technical Reports Server (NTRS)

Striepe, Scott A.; Blanchard, Robert C.; Kirsch, Michael F.; Fowler, Wallace T.

2007-01-01

On January 14, 2005, ESA's Huygens probe separated from NASA's Cassini spacecraft, entered the Titan atmosphere and landed on its surface. As part of NASA Engineering Safety Center Independent Technical Assessment of the Huygens entry, descent, and landing, and an agreement with ESA, NASA provided results of all EDL analyses and associated findings to the Huygens project team prior to probe entry. In return, NASA was provided the flight data from the probe so that trajectory reconstruction could be done and simulation models assessed. Trajectory reconstruction of the Huygens entry probe at Titan was accomplished using two independent approaches: a traditional method and a POST2-based method. Results from both approaches are discussed in this paper.

Treatment of cells with alkaline borate buffer extends the capability of interphase FISH mapping.

PubMed

Yokota, H; van den Engh, G; Mostert, M; Trask, B J

1995-01-20

Interphase fluorescence in situ hybridization (FISH) has been shown to be a means to map DNA sequences relative to each other in the 100 kb to 1-2 Mb genomic-separation range. At distances below 0.1 Mb, probe sites are infrequently resolved in interphase chromatin. In the 0.1- to 1-Mb range, interphase chromatin can be modeled as a freely flexible chain. The mean square interphase distance between two probes is proportional to the genomic separation between the probes on the linear DNA molecule. Above 1-2 Mb, the relationship between interphase distance and genomic separation changes abruptly and appears to level off. We have used alkaline-borate treatment to expand the capability of interphase FISH mapping. We show here that alkaline-borate treatment increases nuclear diameter, the interphase distance between probes on homologous chromosomes, and the distance between probes on the same chromosome. We also show that the mean square distance between hybridization sites in borate-treated nuclei is proportional to genomic separation up to 4 Mb. Thus, alkaline-borate treatment enhances the capability of interphase FISH mapping by increasing the absolute distance between probes and extending the range of the simple relationship between interphase distance and genomic separation.

Treatment of cells with alkaline borate buffer extends the capability of interphase FISH mapping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yokota, H.; Van Den Engh, G.; Mostert, M.

1995-01-20

Interphase fluorescence in situ hybridization (FISH) has been shown to be a means to map DNA sequences relative to each other in the 100 kb to 1-2 Mb genomic-separation range. At distances below 0.1 Mb, probe sites are infrequently resolved in interphase chromatin. In the 0.1- to 1-Mb range, interphase chromatin can be modeled as a freely flexible chain. The mean square interphase distance between two probes is proportional to the genomic separation between the probes on the linear DNA molecule. Above 1-2 Mb, the relationship between interphase distance and genomic separation changes abruptly and appears to level off. Wemore » have used alkaline-borate treatment to expand the capability of interphase FISH mapping. We show here that alkaline-borate treatment increases nuclear diameter, the interphase distance between probes on homologous chromosomes, and the distance between probes on the same chromosome. We also show that the mean square distance between hybridization sites in borate-treated nuclei is proportional to genomic separation up to 4 Mb. Thus, alkaline-borate treatment enhances the capability of interphase FISH mapping by increasing the absolute distance between probes and extending the range of the simple relationship between interphase distance and genomic separation. 31 refs., 5 figs.« less

Gone in a Flash

NASA Image and Video Library

2005-07-04

This image shows the initial ejecta that resulted when NASA Deep Impact probe collided with comet Tempel 1 on July 3, 2005. It was taken by the spacecraft high-resolution camera 13 seconds after impact.

The ESA mission to Comet Halley

NASA Technical Reports Server (NTRS)

Reinhard, R.

1981-01-01

The Europeon Space Agency's approximately Giotto mission plans for a launch in July 1985 with a Halley encounter in mid-March 1986 4 weeks after the comet's perihelion passage. Giotto carries 10 scientific experiments, a camera, neutral, ion and dust mass spectrometers, a dust impact detector system, various plasma analyzers, a magnetometer and an optical probe. The instruments are described, the principles on which they are based are described, and the experiment key performance data are summarized. The launch constraints the helicentric transfer trajectory, and the encounter scenario are analyzed. The Giotto spacecraft major design criteria, spacecraft subsystem and the ground system are described. The problem of hypervelocity dust particle impacts in the innermost part of the coma, the problem of spacecraft survival, and the adverse effects of impact-generated plasma aroung the spacecraft are considered.

KSC-2014-4488

NASA Image and Video Library

2014-11-13

CAPE CANAVERAL, Fla. – All four of the Magnetospheric Multiscale, or MMS, spacecraft have arrived in the Building 1 high bay of the Astrotech payload processing facility in Titusville, Florida, near Kennedy Space Center. The two MMS spacecraft comprising the upper deck arrived Nov. 12; the two MMS spacecraft comprising the lower stack arrived Oct. 29. The Magnetospheric Multiscale mission is a Solar Terrestrial Probes mission comprising four identically instrumented spacecraft that will use Earth’s magnetosphere as a laboratory to study the microphysics of three fundamental plasma processes: magnetic reconnection, energetic particle acceleration and turbulence. Launch aboard a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station is targeted for March 12, 2015. To learn more about MMS, visit http://mms.gsfc.nasa.gov. Photo credit: NASA/Kim Shiflett

Mission building blocks for outer solar system exploration.

NASA Technical Reports Server (NTRS)

Herman, D.; Tarver, P.; Moore, J.

1973-01-01

Description of the technological building blocks required for exploring the outer planets with maximum scientific yields under stringent resource constraints. Two generic spacecraft types are considered: the Mariner and the Pioneer. Following a discussion of the outer planet mission constraints, the evolutionary development of spacecraft, probes, and propulsion building blocks is presented. Then, program genealogies are shown for Pioneer and Mariner missions and advanced propulsion systems to illustrate the soundness of a program based on spacecraft modification rather than on the development of new spacecraft for each mission. It is argued that, for minimum costs, technological advancement should occur in an evolutionary manner from mission to mission. While this strategy is likely to result in compromises on specific missions, the realization of the overall objectives calls for an advance commitment to the entire mission series.

High Resolution Global Topography of Eros from NEAR Imaging and LIDAR Data

NASA Technical Reports Server (NTRS)

Gaskell, Robert W.; Konopliv, A.; Barnouin-Jha, O.; Scheeres, D.

2006-01-01

Principal Data Products: Ensemble of L-maps from SPC, Spacecraft state, Asteroid pole and rotation. Secondary Products: Global topography model, inertia tensor, gravity. Composite high resolution topography. Three dimensional image maps.

GRAIL Final Resting Spot

NASA Image and Video Library

2012-12-13

These maps of Earth moon highlight the region where the twin spacecraft of NASA Gravity Recovery and Interior Laboratory GRAIL mission will impact on Dec. 17, marking the end of its successful endeavor to map the moon gravity.

Map of Titan - April 2011

NASA Image and Video Library

2011-10-26

This global digital map of Saturn moon Titan was created using images taken by NASA Cassini spacecraft imaging science subsystem ISS. Because of the scattering of light by Titan dense atmosphere, no topographic shading is visible here.

Hall Probe Calibration System Design for the Mu2e Solenoid Field Mapping System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orozco, Charles; Elementi, Luciano; Feher, Sandor

The goal of the Mu2e experiment at Fermilab is to search for charged-lepton flavor violation by looking for neutrino-less muon to electron conversion in the field of the nucleus. The Mu2e experimental apparatus utilizes a complex magnetic field in the muon generation and momentum and charge selection process. Precise knowledge of the magnetic field is crucial. It is planned to map the solenoid field with calibrated 3D Hall probes up to 10 -5 accuracy. Here, this article describes a new design of a Hall probe calibration system that will be used to calibrate 3D Hall probes to better than 10more » -5 accuracy for the Mu2e Solenoid Field Mapping System.« less

Hall Probe Calibration System Design for the Mu2e Solenoid Field Mapping System

DOE PAGES

Orozco, Charles; Elementi, Luciano; Feher, Sandor; ...

2018-02-22

The goal of the Mu2e experiment at Fermilab is to search for charged-lepton flavor violation by looking for neutrino-less muon to electron conversion in the field of the nucleus. The Mu2e experimental apparatus utilizes a complex magnetic field in the muon generation and momentum and charge selection process. Precise knowledge of the magnetic field is crucial. It is planned to map the solenoid field with calibrated 3D Hall probes up to 10 -5 accuracy. Here, this article describes a new design of a Hall probe calibration system that will be used to calibrate 3D Hall probes to better than 10more » -5 accuracy for the Mu2e Solenoid Field Mapping System.« less

The SPHEREx All-Sky Spectral Survey

NASA Astrophysics Data System (ADS)

Bock, James; SPHEREx Science Team

2018-01-01

SPHEREx, a mission in NASA's Medium Explorer (MIDEX) program that was selected for Phase A in August 2017, is an all-sky survey satellite designed to address all three science goals in NASA's astrophysics division, with a single instrument, a wide-field spectral imager. SPHEREx will probe the physics of inflation by measuring non-Gaussianity by studying large-scale structure, surveying a large cosmological volume at low redshifts, complementing high-z surveys optimized to constrain dark energy. The origin of water and biogenic molecules will be investigated in all phases of planetary system formation - from molecular clouds to young stellar systems with protoplanetary disks - by measuring ice absorption spectra. We will chart the origin and history of galaxy formation through a deep survey mapping large-scale spatial power in two deep fields located near the ecliptic poles. Following in the tradition of all-sky missions such as IRAS, COBE and WISE, SPHEREx will be the first all-sky near-infrared spectral survey. SPHEREx will create spectra (0.75 – 4.2 um at R = 41; and 4.2 – 5 um at R = 135) with high sensitivity making background-limited observations using a passively-cooled telescope with a wide field-of-view for large mapping speed. During its two-year mission, SPHEREx will produce four complete all-sky maps that will serve as a rich archive for the astronomy community. With over a billion detected galaxies, hundreds of millions of high-quality stellar and galactic spectra, and over a million ice absorption spectra, the archive will enable diverse scientific investigations including studies of young stellar systems, brown dwarfs, high-redshift quasars, galaxy clusters, the interstellar medium, asteroids and comets. All aspects of the instrument and spacecraft have high heritage. SPHEREx requires no new technologies and carries large technical and resource margins on every aspect of the design. SPHEREx is a partnership between Caltech and JPL, following the successful management structure of the NuSTAR and GALEX missions. The spacecraft will be supplied by Ball Aerospace. The Korea Astronomy and Space Science Institute will contribute test hardware and scientific analysis.

KSC-06pd2792

NASA Image and Video Library

2006-12-11

KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., one of the probes of the THEMIS spacecraft is revealed after the crate and cover were removed. THEMIS, which stands for Time History of Events and Macroscale Interactions during Substorms, comprises five identical probes that will study the dynamic and colorful eruptions of auroras. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

KSC-06pd2793

NASA Image and Video Library

2006-12-11

KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., one of the probes of the THEMIS spacecraft is revealed after the crate and cover were removed. THEMIS, which stands for Time History of Events and Macroscale Interactions during Substorms, comprises five identical probes that will study the dynamic and colorful eruptions of auroras. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton

Effects of the guard electrode on the photoelectron distribution around an electric field sensor

NASA Astrophysics Data System (ADS)

Miyake, Y.; Usui, H.; Kojima, H.

2011-05-01

We have developed a numerical model of a double-probe electric field sensor equipped with a photoelectron guard electrode for the particle-in-cell simulation. The model includes typical elements of modern double-probe sensors on, e.g., BepiColombo/MMO, Cluster, and THEMIS spacecraft, such as a conducting boom and a preamplifier housing called a puck. The puck is also used for the guard electrode, and its potential is negatively biased by reference to the floating spacecraft potential. We apply the proposed model to an analysis of an equilibrium plasma environment around the sensor by assuming that the sun illuminates the spacecraft from the direction perpendicular to the sensor deployment axis. As a simulation result, it is confirmed that a substantial number of spacecraft-originating photoelectrons are once emitted sunward and then fall onto the puck and sensing element positions. In order to effectively repel such photoelectrons coming from the sun direction, a potential hump for electrons, i.e., a negative potential region, should be created in a plasma region around the sunlit side of the guard electrode surface. The simulation results reveal the significance of the guard electrode potential being not only lower than the spacecraft body but also lower than the background plasma potential of the region surrounding the puck and the sensing element. One solution for realizing such an operational condition is to bias the guard potential negatively by reference to the sensor potential because the sensor is usually operated nearly at the background plasma potential.

Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Haley 2

NASA Technical Reports Server (NTRS)

Luna, Michael E.; Collins, Stephen M.

2011-01-01

On November 4, 2010 the already "in-flight" Deep Impact spacecraft flew within 700km of comet 103P/Hartley 2 as part of its extended mission EPOXI, the 5th time to date any spacecraft visited a comet. In 2005, the spacecraft had previously imaged a probe impact comet Tempel 1. The EPOXI flyby marked the first time in history that two comets were explored with the same instruments on a re-used spacecraft-with hardware and software originally designed and optimized for a different mission. This made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby. As part of the spacecraft team preparations, the ADCS team had to perform thorough sequence reviews, key spacecraft activities and onboard calibrations. These activities included: review of background sequences for the initial conditions vector, sun sensor coefficients, and reaction wheel assembly (RWA) de-saturations; design and execution of 10 trajectory correction maneuvers; science calibration of the two telescope instruments; a flight demonstration of the fastest turns conducted by the spacecraft between Earth and comet point; and assessment of RWA health (given RWA problems on other spacecraft).

KSC-04PD-1080

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- A remote camera captures ignition of the Delta II rocket carrying the Gravity Probe B spacecraft from Space Launch Complex 2 on Vandenberg AFB, Calif., at 9:57:24 a.m. PDT.

KSC-03PD-2755

NASA Technical Reports Server (NTRS)

2003-01-01

VANDENBERG AFB, CALIF. In the spacecraft processing facility on North Vandenberg Air Force Base, workers prepare to remove the soft shipping cover from the Gravity Probe B experiment. Immediate processing includes setting up mechanical and electrical ground support equipment, making necessary connections and conditioning the spacecraft battery. The Gravity Probe B will launch a payload of four gyroscopes into low-Earth polar orbit to test two extraordinary predictions of Albert Einsteins general theory of relativity: the geodetic effect (how space and time are warped by the presence of the Earth) and frame dragging (how Earths rotation drags space and time around with it). Once in orbit, for 18 months each gyroscopes spin axis will be monitored as it travels through local spacetime, observing and measuring these effects. The experiment was developed by Stanford University, Lockheed Martin and NASAs Marshall Space Flight Center.

Conjugate Ground-Spacecraft Observations of VLF Chorus Elements

NASA Astrophysics Data System (ADS)

Demekhov, A. G.; Manninen, J.; Santolík, O.; Titova, E. E.

2017-12-01

We present results of simultaneous observations of VLF chorus elements at the ground-based station Kannuslehto in Northern Finland and on board Van Allen Probe A. Visual inspection and correlation analysis of the data reveal one-to-one correspondence of several (at least 12) chorus elements following each other in a sequence. Poynting flux calculated from electromagnetic fields measured by the Electric and Magnetic Field Instrument Suite and Integrated Science instrument on board Van Allen Probe A shows that the waves propagate at small angles to the geomagnetic field and oppositely to its direction, that is, from northern to southern geographic hemisphere. The spacecraft was located at L≃4.1 at a geomagnetic latitude of -12.4∘ close to the plasmapause and inside a localized density inhomogeneity with about 30% density increase and a transverse size of about 600 km. The time delay between the waves detected on the ground and on the spacecraft is about 1.3 s, with ground-based detection leading spacecraft detection. The measured time delay is consistent with the wave travel time of quasi-parallel whistler-mode waves for a realistic profile of the plasma density distribution along the field line. The results suggest that chorus discrete elements can preserve their spectral shape during a hop from the generation region to the ground followed by reflection from the ionosphere and return to the near-equatorial region.

Calibration Results and Anticipated Science Ops for the Parker Solar Probe's SWEAP/SPAN-Electron Analyzers

NASA Astrophysics Data System (ADS)

Whittlesey, P. L.; Larson, D. E.; Livi, R.; Abiad, R.; Parker, C.; Halekas, J. S.; Kasper, J. C.; Korreck, K. E.

2017-12-01

We present the SPAN-E calibration results and science operation plans this instrument on the Parker Solar Probe mission. SPAN-E is a pair of highly configurable ESA sensors, one on the RAM side of the spacecraft (SPAN-Ae) and one on anti-RAM (SPAN-B). Together, SPAN-E will jointly measure the full 3D thermal and suprathermal electron distribution function at cadences as fast as 4.58Hz. Joined with the SPAN-Ai and SPC instruments that are part of the Solar Wind Electrons, Alphas, and Protons (SWEAP) suite, SPAN-E will measure the solar coronal plasma across a range of energies and densities with a FOV over >90% of the sky, returning data over a 7 year long PSP mission lifetime. The SPAN-E instruments have passed environmental testing at the instrument level, and the final instrument calibrations are complete. This presentation details the final instrument calibration results as performed at UCB/SSL after environmental testing, and details the planned configurations for PSP's first orbit. In addition, the PSP spacecraft's magnetic fields are expected to distort the measured electron VDFs at low energies, thus we present a novel computer vision method of measuring and modeling the spacecraft magnetic fields as seen during an observatory-level "swing" test. Ultimately, the model will feed into an algorithm for ground corrections to electron VDFs distorted by these stray spacecraft magnetic fields.

Augmentation method of XPNAV in Mars orbit based on Phobos and Deimos observations

NASA Astrophysics Data System (ADS)

Rong, Jiao; Luping, Xu; Zhang, Hua; Cong, Li

2016-11-01

Autonomous navigation for Mars probe spacecraft is required to reduce the operation costs and enhance the navigation performance in the future. X-ray pulsar-based navigation (XPNAV) is a potential candidate to meet this requirement. This paper addresses the use of the Mars' natural satellites to improve XPNAV for Mars probe spacecraft. Two observation variables of the field angle and natural satellites' direction vectors of Mars are added into the XPNAV positioning system. The measurement model of field angle and direction vectors is formulated by processing satellite image of Mars obtained from optical camera. This measurement model is integrated into the spacecraft orbit dynamics to build the filter model. In order to estimate position and velocity error of the spacecraft and reduce the impact of the system noise on navigation precision, an adaptive divided difference filter (ADDF) is applied. Numerical simulation results demonstrate that the performance of ADDF is better than Unscented Kalman Filter (UKF) DDF and EKF. In view of the invisibility of Mars' natural satellites in some cases, a visibility condition analysis is given and the augmented XPNAV in a different visibility condition is numerically simulated. The simulation results show that the navigation precision is evidently improved by using the augmented XPNAV based on the field angle and natural satellites' direction vectors of Mars in a comparison with the conventional XPNAV.

First Results from ARTEMIS, a New Two-Spacecraft Lunar Mission: Counter-Streaming Plasma Populations in the Lunar Wake

NASA Technical Reports Server (NTRS)

Halekas, J. S.; Angelopoulos, V.; Sibeck, D. G.; Khurana, K. K.; Russell, C. T.; Delory, G. T.; Farrell, W. M.; McFadden, J. P.; Bonnell, J. W.; Larson, D.;

First Results from ARTEMIS, A New Two-Spacecraft Lunar Mission: Counter-Streaming Plasma Populations in the Lunar Wake

NASA Technical Reports Server (NTRS)

Halekas, J. S.; Angelopoulos, V.; Sibeck, D. G.; Khurana, K. K.; Russell, C. T.; Delory, G. T.; Farrell, W. M.; McFadden, J. P.; Bonnell, J. W.; Larson, D.;

Science Objectives and Rationale for the Radiation Belt Storm Probes Mission

NASA Technical Reports Server (NTRS)

Mauk, B.H.; Fox, Nicola J.; Kanekal, S. G.; Kessel, R. L.; Sibek, D. G.; Ukhorskiy, A.

2012-01-01

The NASA Radiation Belt Storm Probes (RBSP) mission addresses how populationsof high energy charged particles are created, vary, and evolve in space environments,and specifically within Earths magnetically trapped radiation belts. RBSP, with a nominallaunch date of August 2012, comprises two spacecraft making in situ measurements for atleast 2 years in nearly the same highly elliptical, low inclination orbits (1.1 5.8 RE, 10).The orbits are slightly different so that 1 spacecraft laps the other spacecraft about every2.5 months, allowing separation of spatial from temporal effects over spatial scales rangingfrom 0.1 to 5 RE. The uniquely comprehensive suite of instruments, identical on the twospacecraft, measures all of the particle (electrons, ions, ion composition), fields (E and B),and wave distributions (dE and dB) that are needed to resolve the most critical science questions.Here we summarize the high level science objectives for the RBSP mission, providehistorical background on studies of Earth and planetary radiation belts, present examples ofthe most compelling scientific mysteries of the radiation belts, present the mission design ofthe RBSP mission that targets these mysteries and objectives, present the observation andmeasurement requirements for the mission, and introduce the instrumentation that will deliverthese measurements. This paper references and is followed by a number of companionpapers that describe the details of the RBSP mission, spacecraft, and instruments.

Automated clustering of probe molecules from solvent mapping of protein surfaces: new algorithms applied to hot-spot mapping and structure-based drug design

NASA Astrophysics Data System (ADS)

Lerner, Michael G.; Meagher, Kristin L.; Carlson, Heather A.

2008-10-01

Use of solvent mapping, based on multiple-copy minimization (MCM) techniques, is common in structure-based drug discovery. The minima of small-molecule probes define locations for complementary interactions within a binding pocket. Here, we present improved methods for MCM. In particular, a Jarvis-Patrick (JP) method is outlined for grouping the final locations of minimized probes into physical clusters. This algorithm has been tested through a study of protein-protein interfaces, showing the process to be robust, deterministic, and fast in the mapping of protein "hot spots." Improvements in the initial placement of probe molecules are also described. A final application to HIV-1 protease shows how our automated technique can be used to partition data too complicated to analyze by hand. These new automated methods may be easily and quickly extended to other protein systems, and our clustering methodology may be readily incorporated into other clustering packages.

2nd International Planetary Probe Workshop

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj; Martinez, Ed; Arcadi, Marla

2005-01-01

Included are presentations from the 2nd International Planetary Probe Workshop. The purpose of the second workshop was to continue to unite the community of planetary scientists, spacecraft engineers and mission designers and planners; whose expertise, experience and interests are in the areas of entry probe trajectory and attitude determination, and the aerodynamics/aerothermodynamics of planetary entry vehicles. Mars lander missions and the first probe mission to Titan made 2004 an exciting year for planetary exploration. The Workshop addressed entry probe science, engineering challenges, mission design and instruments, along with the challenges of reconstruction of the entry, descent and landing or the aerocapture phases. Topics addressed included methods, technologies, and algorithms currently employed; techniques and results from the rich history of entry probe science such as PAET, Venera/Vega, Pioneer Venus, Viking, Galileo, Mars Pathfinder and Mars MER; upcoming missions such as the imminent entry of Huygens and future Mars entry probes; and new and novel instrumentation and methodologies.

Global Topographic Map of Titan

NASA Image and Video Library

2013-05-15

Using data from NASA Cassini spacecraft, scientists have created the first global topographic map of Saturn moon Titan, giving researchers a 3-D tool for learning more about one of the most Earthlike and interesting worlds in the solar system.

The structure of the inner heliosphere from Pioneer Venus and IMP observations

NASA Technical Reports Server (NTRS)

Gazis, P. R.; Barnes, A.; Mihalov, J. D.; Lazarus, A. J.

1992-01-01

The IMP 8 and Pioneer Venus Orbiter (PVO) spacecraft explore the region of heliographic latitudes between 8 deg N and 8 deg S. Solar wind observations from these spacecraft are used to construct synoptic maps of solar wind parameters in this region. These maps provide an explicit picture of the structure of high speed streams near 1 AU and how that structure varies with time. From 1982 until early 1985, solar wind parameters varied little with latitude. During the last solar minimum, the solar wind developed strong latitudinal structure; high speed streams were excluded from the vicinity of the solar equator. Synoptic maps of solar wind speed are compared with maps of the coronal source surface magnetic field. This comparison reveals the expected correlation between solar wind speed near 1 AU, the strength of the coronal magnetic field, and distance from the coronal neutral line.

The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission

NASA Astrophysics Data System (ADS)

Wygant, J. R.; Bonnell, J. W.; Goetz, K.; Ergun, R. E.; Mozer, F. S.; Bale, S. D.; Ludlam, M.; Turin, P.; Harvey, P. R.; Hochmann, R.; Harps, K.; Dalton, G.; McCauley, J.; Rachelson, W.; Gordon, D.; Donakowski, B.; Shultz, C.; Smith, C.; Diaz-Aguado, M.; Fischer, J.; Heavner, S.; Berg, P.; Malsapina, D. M.; Bolton, M. K.; Hudson, M.; Strangeway, R. J.; Baker, D. N.; Li, X.; Albert, J.; Foster, J. C.; Chaston, C. C.; Mann, I.; Donovan, E.; Cully, C. M.; Cattell, C. A.; Krasnoselskikh, V.; Kersten, K.; Brenneman, A.; Tao, J. B.

2013-11-01

The Electric Fields and Waves (EFW) Instruments on the two Radiation Belt Storm Probe (RBSP) spacecraft (recently renamed the Van Allen Probes) are designed to measure three dimensional quasi-static and low frequency electric fields and waves associated with the major mechanisms responsible for the acceleration of energetic charged particles in the inner magnetosphere of the Earth. For this measurement, the instrument uses two pairs of spherical double probe sensors at the ends of orthogonal centripetally deployed booms in the spin plane with tip-to-tip separations of 100 meters. The third component of the electric field is measured by two spherical sensors separated by ˜15 m, deployed at the ends of two stacer booms oppositely directed along the spin axis of the spacecraft. The instrument provides a continuous stream of measurements over the entire orbit of the low frequency electric field vector at 32 samples/s in a survey mode. This survey mode also includes measurements of spacecraft potential to provide information on thermal electron plasma variations and structure. Survey mode spectral information allows the continuous evaluation of the peak value and spectral power in electric, magnetic and density fluctuations from several Hz to 6.5 kHz. On-board cross-spectral data allows the calculation of field-aligned wave Poynting flux along the magnetic field. For higher frequency waveform information, two different programmable burst memories are used with nominal sampling rates of 512 samples/s and 16 k samples/s. The EFW burst modes provide targeted measurements over brief time intervals of 3-d electric fields, 3-d wave magnetic fields (from the EMFISIS magnetic search coil sensors), and spacecraft potential. In the burst modes all six sensor-spacecraft potential measurements are telemetered enabling interferometric timing of small-scale plasma structures. In the first burst mode, the instrument stores all or a substantial fraction of the high frequency measurements in a 32 gigabyte burst memory. The sub-intervals to be downloaded are uplinked by ground command after inspection of instrument survey data and other information available on the ground. The second burst mode involves autonomous storing and playback of data controlled by flight software algorithms, which assess the "highest quality" events on the basis of instrument measurements and information from other instruments available on orbit. The EFW instrument provides 3-d wave electric field signals with a frequency response up to 400 kHz to the EMFISIS instrument for analysis and telemetry (Kletzing et al. Space Sci. Rev. 2013).

Sloshing dynamics on rotating helium dewar tank

NASA Technical Reports Server (NTRS)

Hung, R. J.

1993-01-01

The generalized mathematical formulation of sloshing dynamics for partially filled liquid of cryogenic superfluid helium II in dewar containers driven by both the gravity gradient and jitter accelerations applicable to scientific spacecraft which is eligible to carry out spinning motion and/or slew motion for the purpose to perform scientific observation during the normal spacecraft operation are investigated. An example is given with Gravity Probe-B (GP-B) spacecraft which is responsible for the sloshing dynamics. The jitter accelerations include slew motion, spinning motion, atmospheric drag on the spacecraft, spacecraft attitude motions arising from machinery vibrations, thruster firing, pointing control of spacecraft, crew motion, etc. Explicit mathematical expressions to cover these forces acting on the spacecraft fluid systems are derived. The numerical computation of sloshing dynamics were based on the non-inertia frame spacecraft bound coordinate, and solve time dependent, three-dimensional formulations of partial differential equations subject to initial and boundary conditions. The explicit mathematical expressions of boundary conditions to cover capillary force effect on the liquid vapor interface in microgravity environments are also derived. The formulations of fluid moment and angular moment fluctuations in fluid profiles induced by the sloshing dynamics, together with fluid stress and moment fluctuations exerted on the spacecraft dewar containers were derived. Results were widely published in the open journals.

Numerical studies of the surface tension effect of cryogenic liquid helium

NASA Technical Reports Server (NTRS)

Hung, R. J.

1994-01-01

The generalized mathematical formulation of sloshing dynamics for partially filled liquid of cryogenic superfluid helium II in dewar containers driven by both the gravity gradient and jitter accelerations applicable to scientific spacecraft which is eligible to carry out spinning motion and/or slew motion for the purpose of performing scientific observation during the normal spacecraft operation is investigated. An example is given with Gravity Probe-B (GP-B) spacecraft which is responsible for the sloshing dynamics. The jitter accelerations include slew motion, spinning motion, atmospheric drag on the spacecraft, spacecraft attitude motions arising from machinery vibrations, thruster firing, pointing control of spacecraft, crew motion, etc. Explicit mathematical expressions to cover these forces acting on the spacecraft fluid systems are derived. The numerical computation of sloshing dynamics has been based on the non-inertia frame spacecraft bound coordinate, and solve time-dependent, three-dimensional formulations of partial differential equations subject to initial and boundary conditions. The explicit mathematical expressions of boundary conditions to cover capillary force effect on the liquid vapor interface in microgravity environments are also derived. The formulations of fluid moment and angular moment fluctuations in fluid profiles induced by the sloshing dynamics, together with fluid stress and moment fluctuations exerted on the spacecraft dewar containers, have been derived.

The FTMap family of web servers for determining and characterizing ligand binding hot spots of proteins

PubMed Central

Kozakov, Dima; Grove, Laurie E.; Hall, David R.; Bohnuud, Tanggis; Mottarella, Scott; Luo, Lingqi; Xia, Bing; Beglov, Dmitri; Vajda, Sandor

2016-01-01

FTMap is a computational mapping server that identifies binding hot spots of macromolecules, i.e., regions of the surface with major contributions to the ligand binding free energy. To use FTMap, users submit a protein, DNA, or RNA structure in PDB format. FTMap samples billions of positions of small organic molecules used as probes and scores the probe poses using a detailed energy expression. Regions that bind clusters of multiple probe types identify the binding hot spots, in good agreement with experimental data. FTMap serves as basis for other servers, namely FTSite to predict ligand binding sites, FTFlex to account for side chain flexibility, FTMap/param to parameterize additional probes, and FTDyn to map ensembles of protein structures. Applications include determining druggability of proteins, identifying ligand moieties that are most important for binding, finding the most bound-like conformation in ensembles of unliganded protein structures, and providing input for fragment based drug design. FTMap is more accurate than classical mapping methods such as GRID and MCSS, and is much faster than the more recent approaches to protein mapping based on mixed molecular dynamics. Using 16 probe molecules, the FTMap server finds the hot spots of an average size protein in less than an hour. Since FTFlex performs mapping for all low energy conformers of side chains in the binding site, its completion time is proportionately longer. PMID:25855957

Uprobe: a genome-wide universal probe resource for comparative physical mapping in vertebrates.

PubMed

Kellner, Wendy A; Sullivan, Robert T; Carlson, Brian H; Thomas, James W

2005-01-01

Interspecies comparisons are important for deciphering the functional content and evolution of genomes. The expansive array of >70 public vertebrate genomic bacterial artificial chromosome (BAC) libraries can provide a means of comparative mapping, sequencing, and functional analysis of targeted chromosomal segments that is independent and complementary to whole-genome sequencing. However, at the present time, no complementary resource exists for the efficient targeted physical mapping of the majority of these BAC libraries. Universal overgo-hybridization probes, designed from regions of sequenced genomes that are highly conserved between species, have been demonstrated to be an effective resource for the isolation of orthologous regions from multiple BAC libraries in parallel. Here we report the application of the universal probe design principal across entire genomes, and the subsequent creation of a complementary probe resource, Uprobe, for screening vertebrate BAC libraries. Uprobe currently consists of whole-genome sets of universal overgo-hybridization probes designed for screening mammalian or avian/reptilian libraries. Retrospective analysis, experimental validation of the probe design process on a panel of representative BAC libraries, and estimates of probe coverage across the genome indicate that the majority of all eutherian and avian/reptilian genes or regions of interest can be isolated using Uprobe. Future implementation of the universal probe design strategy will be used to create an expanded number of whole-genome probe sets that will encompass all vertebrate genomes.

KSC-04PD-1082

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- A remote wide-angle camera captures liftoff of the Delta II rocket carrying the Gravity Probe B spacecraft from Space Launch Complex 2 on Vandenberg AFB, Calif., at 9:57:24 a.m. PDT.

New Horizons Best Close-Up of Pluto Surface

NASA Image and Video Library

2016-05-27

This mosaic strip, extending across the hemisphere that faced the New Horizons spacecraft as it flew past Pluto on July 14, 2015, now includes all of the highest-resolution images taken by the NASA probe.

KSC-04PD-1079

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- This photo of the Delta II rocket carrying the Gravity Probe B spacecraft was taken minutes before launch from Space Launch Complex 2 on Vandenberg AFB, Calif., at 9:57:24 a.m. PDT.

A maize map standard with sequenced core markers, grass genome reference points and 932 expressed sequence tagged sites (ESTs) in a 1736-locus map.

PubMed Central

Davis, G L; McMullen, M D; Baysdorfer, C; Musket, T; Grant, D; Staebell, M; Xu, G; Polacco, M; Koster, L; Melia-Hancock, S; Houchins, K; Chao, S; Coe, E H

1999-01-01

We have constructed a 1736-locus maize genome map containing1156 loci probed by cDNAs, 545 probed by random genomic clones, 16 by simple sequence repeats (SSRs), 14 by isozymes, and 5 by anonymous clones. Sequence information is available for 56% of the loci with 66% of the sequenced loci assigned functions. A total of 596 new ESTs were mapped from a B73 library of 5-wk-old shoots. The map contains 237 loci probed by barley, oat, wheat, rice, or tripsacum clones, which serve as grass genome reference points in comparisons between maize and other grass maps. Ninety core markers selected for low copy number, high polymorphism, and even spacing along the chromosome delineate the 100 bins on the map. The average bin size is 17 cM. Use of bin assignments enables comparison among different maize mapping populations and experiments including those involving cytogenetic stocks, mutants, or quantitative trait loci. Integration of nonmaize markers in the map extends the resources available for gene discovery beyond the boundaries of maize mapping information into the expanse of map, sequence, and phenotype information from other grass species. This map provides a foundation for numerous basic and applied investigations including studies of gene organization, gene and genome evolution, targeted cloning, and dissection of complex traits. PMID:10388831

Working Toward Seamless Infrared Maps of Titan

NASA Image and Video Library

2016-03-24

Each of these two montages shows four synthetic views of Titan created using data acquired by NASA Cassini spacecraft between 2004 and 2015. With each flyby, a brief opportunity to add small pieces to the overall mapping coverage of Titan.

High Spatial Resolution Europa Coverage by the Galileo Near Infrared Mapping Spectrometer NIMS

NASA Image and Video Library

1998-03-26

NASA Galileo spacecraft, which was used to map the mineral and ice properties over the surfaces of the Jovian moons, producing global spectral images for small selected regions on the satellites in 1996-97.

Polar Maps of Thermal and Epithermal Neutrons

NASA Image and Video Library

2002-05-28

Observations by NASA Mars Odyssey spacecraft show views of the polar regions of Mars in thermal neutrons top and epithermal neutrons bottom. In these maps, deep blue indicates a low amount of neutrons and red indicates a high amount.

KSC-97PC1347

NASA Image and Video Library

1997-09-07

The Cassini spacecraft, with its attached Huygens probe, is lowered from Launch Pad 40 at Cape Canaveral Air Station for its return trip to the Payload Hazardous Servicing Facility (PHSF). Damage to thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. Further internal inspection, insulation repair and a cleaning of the probe are now required. Mission managers are targeting a mid-October launch date after Cassini returns to the pad and is once again placed atop its Titan IVB expendable launch vehicle. Cassini will explore the Saturnian system, including the planet’s rings, while the Huygens probe will explore the moon Titan

Outer planet atmospheric entry probes - An overview of technology readiness

NASA Technical Reports Server (NTRS)

Vojvodich, N. S.; Reynolds, R. T.; Grant, T. L.; Nachtsheim, P. R.

1975-01-01

Entry probe systems for characterizing, by in situ measurements, the atmospheric properties, chemical composition, and cloud structure of the planets Saturn, Uranus, and Jupiter are examined from the standpoint of unique mission requirements, associated subsystem performance, and degree of commonality of design. Past earth entry vehicles (PAET) and current planetary spacecraft (Pioneer Venus probes and Viking lander) are assessed to identify the extent of potential subsystem inheritance, as well as to establish the significant differences, in both form and function, relative to outer planet requirements. Recent research results are presented and reviewed for the most critical probe technology areas, including: science accommodation, telecommunication, and entry heating and thermal protection. Finally presented is a brief discussion of the use of decision analysis techniques for quantifying various probe heat-shield test alternatives and performance risk.

8th Spacecraft Charging Technology Conference

NASA Technical Reports Server (NTRS)

Minor, J. L. (Compiler)

2004-01-01

The 8th Spacecraft Charging Technology Conference was held in Huntsville, Alabama, October 20-24, 2003. Hosted by NASA s Space Environments and Effects (SEE) Program and co-sponsored by the Air Force Research Laboratory (AFRL) and the European Space Agency (ESA), the 2003 conference saw attendance from eleven countries with over 65 oral papers and 18 poster papers. Presentation topics highlighted the latest in spacecraft charging mitigation techniques and on-orbit investigations, including: Plasma Propulsion and Tethers; Ground Testing Techniques; Interactions of Spacecraft and Systems With the Natural and Induced Plasma Environment; Materials Characterizations; Models and Computer Simulations; Environment Specifications; Current Collection and Plasma Probes in Space Plasmas; On-Orbit Investigations. A round-table discussion of international standards regarding electrostatic discharge (ESD) testing was also held with the promise of continued discussions in the off years and an official continuation at the next conference.

KSC-2014-4489

NASA Image and Video Library

2014-11-13

CAPE CANAVERAL, Fla. – The Magnetospheric Multiscale, or MMS, spacecraft will undergo final processing for launch now that all four are in the Building 1 high bay of the Astrotech payload processing facility in Titusville, Florida, near Kennedy Space Center. The two MMS spacecraft comprising the upper deck arrived Nov. 12; the two MMS spacecraft comprising the lower stack arrived Oct. 29. The Magnetospheric Multiscale mission is a Solar Terrestrial Probes mission comprising four identically instrumented spacecraft that will use Earth’s magnetosphere as a laboratory to study the microphysics of three fundamental plasma processes: magnetic reconnection, energetic particle acceleration and turbulence. Launch aboard a United Launch Alliance Atlas V rocket from Space Launch Complex 41 on Cape Canaveral Air Force Station is targeted for March 12, 2015. To learn more about MMS, visit http://mms.gsfc.nasa.gov. Photo credit: NASA/Kim Shiflett

Periodic variations in the signal-to-noise ratios of signals received from the ICE spacecraft

NASA Technical Reports Server (NTRS)

Nadeau, T.

1986-01-01

Data from the ICE probe to comet Giacobini-Zinner are analyzed to determine the effects of spacecraft rotation upon the signal to noise ratio (SNR) for the two channels of data. In addition, long-term variations from sources other than rotations are considered. Results include a pronounced SNR variation over a period of three seconds (one rotation) and a lesser effect over a two minute period (possibly due to the receiving antenna conscan).

JPL-20180505-INSIGHf-0001-NASA InSight on Its Way to Mars

NASA Image and Video Library

2018-05-05

Making history as the first interplanetary launch from the West Coast, NASA's InSight spacecraft is now soaring towards Mars. The spacecraft, which lifted off from Vandenberg Air Force Base in Central California, will be the first mission to study the deep interior of Mars. Its instruments include a seismometer to detect marsquakes for the first time and a heat flow p[robe that will embed itself as deep as about 16 feet (5 meters) below the surface of Mars.

A Survey of Real-Time Operating Systems and Virtualization Solutions for Space Systems

DTIC Science & Technology

2015-03-01

probe, an unmanned spacecraft orbiting Mercury (“Messenger,” n.d.; “VxWorks Space,” n.d.). SpaceX , the private space travel company, uses an unspecified...VxWorks platform on its Dragon reusable spacecraft (“ SpaceX ,” n.d.). 5 Supports the 1003.1 standard but does not provide process creation...2013, March 6). ELC: SpaceX lessons learned. Retrieved from http://lwn.net/ Articles/540368/ 112 Embedded hardware. (n.d.). Retrieved

A background correction algorithm for Van Allen Probes MagEIS electron flux measurements

DOE PAGES

Claudepierre, S. G.; O'Brien, T. P.; Blake, J. B.; ...

2015-07-14

We describe an automated computer algorithm designed to remove background contamination from the Van Allen Probes Magnetic Electron Ion Spectrometer (MagEIS) electron flux measurements. We provide a detailed description of the algorithm with illustrative examples from on-orbit data. We find two primary sources of background contamination in the MagEIS electron data: inner zone protons and bremsstrahlung X-rays generated by energetic electrons interacting with the spacecraft material. Bremsstrahlung X-rays primarily produce contamination in the lower energy MagEIS electron channels (~30–500 keV) and in regions of geospace where multi-M eV electrons are present. Inner zone protons produce contamination in all MagEIS energymore » channels at roughly L < 2.5. The background-corrected MagEIS electron data produce a more accurate measurement of the electron radiation belts, as most earlier measurements suffer from unquantifiable and uncorrectable contamination in this harsh region of the near-Earth space environment. These background-corrected data will also be useful for spacecraft engineering purposes, providing ground truth for the near-Earth electron environment and informing the next generation of spacecraft design models (e.g., AE9).« less

Restoring Redundancy to the Wilkinson Microwave Anisotrophy Probe Propulsion System

NASA Technical Reports Server (NTRS)

O'Donnell, James R., Jr.; Davis, Gary T.; Ward, David K.

2004-01-01

The Wilkinson Microwave Anisotropy Probe is a follow-on to the Differential Microwave Radiometer instrument on the Cosmic Background Explorer. Attitude control system engineers discovered sixteen months before launch that configuration changes after the critical design review had resulted in a significant migration of the spacecraft's center of mass. As a result, the spacecraft no longer had a viable backup control mode in the event of a failure of the negative pitch-axis thruster. A tiger team was formed and identified potential solutions to this problem, such as adding thruster-plume shields to redirect thruster torque, adding or removing mass from the spacecraft, adding an additional thruster, moving thrusters, bending thruster nozzles or propellant tubing, or accepting the loss of redundancy. The project considered the impacts on mass, cost, fuel budget, and schedule for each solution, and decided to bend the propellant tubing of the two roll-control thrusters to allow the pair to be used for backup control in the negative pitch axis. This paper discusses the problem and the potential solutions, and documents the hardware and software changes and verification performed. Flight data are presented to show the on-orbit performance of the propulsion system and lessons learned are described.

Spacecraft Will Communicate "on the Fly"

NASA Technical Reports Server (NTRS)

Laufenberg, Lawrence

2003-01-01

As NASA probes deeper into space, the distance between sensor and scientist increases, as does the time delay. NASA needs to close that gap, while integrating more spacecraft types and missions-from near-Earth orbit to deep space. To speed and integrate communications from space missions to scientists on Earth and back again. NASA needs a comprehensive, high-performance communications network. To this end, the CICT Programs Space Communications (SC) Project is providing technologies for building the Space Internet which will consist of large backbone network, mid-size access networks linked to the backbones, and smaller, ad-hoc network linked to the access network. A key component will be mobile, wireless networks for spacecraft flying in different configurations.

Planetary explorer liquid propulsion study

NASA Technical Reports Server (NTRS)

Mckevitt, F. X.; Eggers, R. F.; Bolz, C. W.

1971-01-01

An analytical evaluation of several candidate monopropellant hydrazine propulsion system approaches is conducted in order to define the most suitable configuration for the combined velocity and attitude control system for the Planetary Explorer spacecraft. Both orbiter and probe-type missions to the planet Venus are considered. The spacecraft concept is that of a Delta launched spin-stabilized vehicle. Velocity control is obtained through preprogrammed pulse-mode firing of the thrusters in synchronism with the spacecraft spin rate. Configuration selection is found to be strongly influenced by the possible error torques induced by uncertainties in thruster operation and installation. The propulsion systems defined are based on maximum use of existing, qualified components. Ground support equipment requirements are defined and system development testing outlined.

Titan/Centaur D-1TTC-5 Helios B flight data report

NASA Technical Reports Server (NTRS)

Adams, K. A.

1976-01-01

The fourth operational flight of the newest NASA unmanned launch vehicle is reported. The spacecraft was the Helios B, the second of two solar probes designed and built by the Federal Republic of Germany. The primary mission objective, to place the Helios spacecraft on a heliocentric orbit in the ecliptic plane with a perihelion distance of 0.29 AU, was successfully accomplished. After successful injection of the Helios spacecraft, a series of experiments were performed with the Centaur stage to demonstrate its operational capabilities. All objectives of the extended mission phase were successfully met. This report presents the analysis of the launch vehicle flight data for the primary mission phase of the TC-5 flight.

Multibody dynamical modeling for spacecraft docking process with spring-damper buffering device: A new validation approach

NASA Astrophysics Data System (ADS)

Daneshjou, Kamran; Alibakhshi, Reza

2018-01-01

In the current manuscript, the process of spacecraft docking, as one of the main risky operations in an on-orbit servicing mission, is modeled based on unconstrained multibody dynamics. The spring-damper buffering device is utilized here in the docking probe-cone system for micro-satellites. Owing to the impact occurs inevitably during docking process and the motion characteristics of multibody systems are remarkably affected by this phenomenon, a continuous contact force model needs to be considered. Spring-damper buffering device, keeping the spacecraft stable in an orbit when impact occurs, connects a base (cylinder) inserted in the chaser satellite and the end of docking probe. Furthermore, by considering a revolute joint equipped with torsional shock absorber, between base and chaser satellite, the docking probe can experience both translational and rotational motions simultaneously. Although spacecraft docking process accompanied by the buffering mechanisms may be modeled by constrained multibody dynamics, this paper deals with a simple and efficient formulation to eliminate the surplus generalized coordinates and solve the impact docking problem based on unconstrained Lagrangian mechanics. By an example problem, first, model verification is accomplished by comparing the computed results with those recently reported in the literature. Second, according to a new alternative validation approach, which is based on constrained multibody problem, the accuracy of presented model can be also evaluated. This proposed verification approach can be applied to indirectly solve the constrained multibody problems by minimum required effort. The time history of impact force, the influence of system flexibility and physical interaction between shock absorber and penetration depth caused by impact are the issues followed in this paper. Third, the MATLAB/SIMULINK multibody dynamic analysis software will be applied to build impact docking model to validate computed results and then, investigate the trajectories of both satellites to take place the successful capture process.

Interstellar Probe: First Step to the Stars

NASA Astrophysics Data System (ADS)

McNutt, R. L., Jr.

2017-12-01

The idea of an "Interstellar Probe," a robotic spacecraft traveling into the nearby interstellar medium for the purpose of scientific investigation, dates to the mid-1960s. The Voyager Interstellar Mission (VIM), an "accidental" 40-year-old by-product of the Grand Tour of the solar system, has provided initial answers to the problem of the global heliospheric configuration and the details of its interface with interstellar space. But the twin Voyager spacecraft have, at most, only another decade of lifetime, and only Voyager 1 has emerged from the heliosheath interaction region. To understand the nature of the interaction, a near-term mission to the "near-by" interstellar medium with modern and focused instrumentation remains a compelling priority. Imaging of energetic neutral atoms (ENAs) by the Ion Neutral CAmera (INCA) on Cassini and from the Interstellar Boundary Explorer (IBEX) in Earth orbit have provided significant new insights into the global interaction region but point to discrepancies with our current understanding. Exploring "as far as possible" into "pristine" interstellar space can resolve these. Hence, reaching large heliocentric distances rapidly is a driver for an Interstellar Probe. Such a mission is timely; understanding the interstellar context of exoplanet systems - and perhaps the context for the emergence of life both here and there - hinges upon what we can discover within our own stellar neighborhood. With current spacecraft technology and high-capability launch vehicles, such as the Space Launch System (SLS), a small, but extremely capable spacecraft, could be dispatched to the near-by interstellar medium with at least twice the speed of the Voyagers. Challenges remain with payload mass and power constraints for optimized science measurements. Mission longevity, as experienced by, but not designed into, the Voyagers, communications capability, and radioisotope power system performance and lifetime are solvable engineering challenges. Such a robotic craft can be built, and could be built and launched soon - to enable our first deliberate step to the stars.

Laboratory Evaluation and Application of Microwave Absorption Properties under Simulated Conditions for Planetary Atmospheres

NASA Technical Reports Server (NTRS)

Steffes, Paul G.

2002-01-01

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments, entry probe radio signal absorption measurements, and earth-based or spacecraft-based radio astronomical (emission) observations can be used to infer abundances of microwave absorbing constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically-derived microwave absorption properties for such atmospheric constituents, or the use of laboratory measurements of such properties taken under environmental conditions that are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. Laboratory measurements have shown that the centimeter-wavelength opacity from gaseous phosphine (PH3) under simulated conditions for the outer planets far exceeds that predicted from theory over a wide range of temperatures and pressures. This fundamentally changed the resulting interpretation of Voyager radio occultation data at Saturn and Neptune. It also directly impacts planning and scientific goals for study of Saturn's atmosphere with the Cassini Radio Science Experiment and the Rossini RADAR instrument. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both spacecraft entry probe and orbiter (or flyby) radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. It has been the goal of this investigation to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft- and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres,

KSC-97PC1804

NASA Image and Video Library

1997-12-18

Lockheed Martin Missile Systems integration and test staff prepare NASA’s Lunar Prospector spacecraft for mating to the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched for NASA on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon’s surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m

KSC-97PC1806

NASA Image and Video Library

1997-12-18

Lockheed Martin Missile Systems integration and test staff join NASA’s Lunar Prospector spacecraft to the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon’s surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m

KSC-97PC1805

NASA Image and Video Library

1997-12-18

Lockheed Martin Missile Systems integration and test staff move NASA’s Lunar Prospector spacecraft over the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon’s surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m

KSC-97PC1803

NASA Image and Video Library

1997-12-18

Lockheed Martin Missile Systems technicians prepare NASA’s Lunar Prospector spacecraft for mating to the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched for NASA on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon’s surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m

KSC-97PC1807

NASA Image and Video Library

1997-12-18

Lockheed Martin Missile Systems integration and test staff join NASA’s Lunar Prospector spacecraft atop the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon’s surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m

Lunar Prospector mated to 4th stage

NASA Technical Reports Server (NTRS)

1997-01-01

KENNEDY SPACE CENTER, FLA. -- Lockheed Martin Missile Systems integration and test staff join NASA's Lunar Prospector spacecraft to the Trans Lunar Injection Module of the spacecraft at Astrotech, a commercial payload processing facility, in Titusville, Fla. The small robotic spacecraft, to be launched on an Athena II launch vehicle by Lockheed Martin, is designed to provide the first global maps of the Moon's surface compositional elements and its gravitational and magnetic fields. The launch of Lunar Prospector is scheduled for Jan. 5, 1998 at 8:31 p.m.

The Small Body Mapping Tool (SBMT) for Accessing, Visualizing, and Analyzing Spacecraft Data in Three Dimensions

NASA Astrophysics Data System (ADS)

Barnouin, O. S.; Ernst, C. M.; Daly, R. T.

2018-04-01

The free, publicly available Small Body Mapping Tool (SBMT) developed at the Johns Hopkins University Applied Physics Laboratory is a powerful, easy-to-use tool for accessing and analyzing data from small bodies.

Southern Hemisphere Neutron Map

NASA Image and Video Library

2002-03-01

NASA Mars Odyssey spacecraft produced this high-energy neutron detector map of neutrons in Mars southern hemisphere. The blue region around the south pole indicates a high content of hydrogen in the upper 2 to 3 meters 7 to 10 feet of the surface.

KSC-04PD-1084

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- After launch, the Delta II rocket carrying the Gravity Probe B spacecraft pitches over and starts heading downrange from Space Launch Complex 2 on Vandenberg AFB, Calif. Liftoff occurred at 9:57:24 a.m. PDT.

Global, Energy-Dependent Ring Current Response During Two Large Storms

NASA Astrophysics Data System (ADS)

Goldstein, J.; Angelopoulos, V.; Burch, J. L.; De Pascuale, S.; Fuselier, S. A.; Genestreti, K. J.; Kurth, W. S.; LLera, K.; McComas, D. J.; Reeves, G. D.; Spence, H. E.; Valek, P. W.

2015-12-01

Two recent large (~200 nT) geomagnetic storms occurred during 17--18 March 2015 and 22--23 June 2015. The global, energy-dependent ring current response to these two extreme events is investigated using both global imaging and multi-point in situ observations. Energetic neutral atom (ENA) imaging by the Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) mission provides a global view of ring current ions. Local measurements are provided by two multi-spacecraft missions. The two Van Allen Probes measure in situ plasma (including ion composition) and fields at ring current and plasmaspheric L values. The recently launched Magnetospheric Multiscale (MMS) comprises four spacecraft that have just begun to measure particles (including ion composition) and fields at outer magnetospheric L-values. We analyze the timing and energetics of the stormtime evolution of ring current ions, both trapped and precipitating, using TWINS ENA images and in situ data by the Van Allen Probes and MMS.

Using SFOC to fly the Magellan Venus mapping mission

NASA Technical Reports Server (NTRS)

Bucher, Allen W.; Leonard, Robert E., Jr.; Short, Owen G.

1993-01-01

Traditionally, spacecraft flight operations at the Jet Propulsion Laboratory (JPL) have been performed by teams of spacecraft experts utilizing ground software designed specifically for the current mission. The Jet Propulsion Laboratory set out to reduce the cost of spacecraft mission operations by designing ground data processing software that could be used by multiple spacecraft missions, either sequentially or concurrently. The Space Flight Operations Center (SFOC) System was developed to provide the ground data system capabilities needed to monitor several spacecraft simultaneously and provide enough flexibility to meet the specific needs of individual projects. The Magellan Spacecraft Team utilizes the SFOC hardware and software designed for engineering telemetry analysis, both real-time and non-real-time. The flexibility of the SFOC System has allowed the spacecraft team to integrate their own tools with SFOC tools to perform the tasks required to operate a spacecraft mission. This paper describes how the Magellan Spacecraft Team is utilizing the SFOC System in conjunction with their own software tools to perform the required tasks of spacecraft event monitoring as well as engineering data analysis and trending.

Cassini Attitude Control Operations Flight Rules and How They are Enforced

NASA Technical Reports Server (NTRS)

Burk, Thomas; Bates, David

2008-01-01

The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. Cassini deployed the European-built Huygens probe which descended through the Titan atmosphere and landed on its surface on January 14, 2005. Operating the Cassini spacecraft is a complex scientific, engineering, and management job. In order to safely operate the spacecraft, a large number of flight rules were developed. These flight rules must be enforced throughout the lifetime of the Cassini spacecraft. Flight rules are defined as any operational limitation imposed by the spacecraft system design, hardware, and software, violation of which would result in spacecraft damage, loss of consumables, loss of mission objectives, loss and/or degradation of science, and less than optimal performance. Flight rules require clear description and rationale. Detailed automated methods have been developed to insure the spacecraft is continuously operated within these flight rules. An overview of all the flight rules allocated to the Cassini Attitude Control and Articulation Subsystem and how they are enforced is presented in this paper.

Mapping the plasmon response of Ag nanoislands on graphite at 100 nm resolution with scanning probe energy loss spectroscopy

NASA Astrophysics Data System (ADS)

Murphy, Shane; Bauer, Karl; Sloan, Peter A.; Lawton, James J.; Tang, Lin; Palmer, Richard E.

2015-12-01

We demonstrate plasmon mapping of Ag nanostructures on graphite using scanning probe energy loss spectroscopy (SPELS) with a spatial resolution of 100 nm. In SPELS, an STM tip is used as a localized source of field-emitted electrons to probe the sample surface. The energy loss spectrum of the backscattered electrons is measured to provide a chemical signature of the surface under the tip. We acquire three images simultaneously with SPELS: i) constant-current field-emission images, which provide topographical information; ii) backscattered electron images, which display material contrast; and iii) SPELS images, where material-dependent features such as plasmons are mapped.

Voyager 1 and 2 Atlas of Six Saturnian Satellites

NASA Technical Reports Server (NTRS)

Batson, R. M.

1984-01-01

Maps, compiled with data gathered primarily by Voyager 1 and 2 spacecraft, are presented which show the diversity among six of the Saturnian moons. Mimas and Enceladus are mapped in detail. Prelimary maps are given for the other four satellites. Diameter, density, albedo, and distance from mother planet, among much more data, is given for each moon.

KSC-05pd2312

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory works on the New Horizons spacecraft before installing one of the panels. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2311

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory work on a panel they are installing on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2314

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory install another panel on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2315

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory install another panel on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2313

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians work on a panel they are installing on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

WMAP C&DH Software

NASA Technical Reports Server (NTRS)

Cudmore, Alan; Leath, Tim; Ferrer, Art; Miller, Todd; Walters, Mark; Savadkin, Bruce; Wu, Ji-Wei; Slegel, Steve; Stagmer, Emory

2007-01-01

The command-and-data-handling (C&DH) software of the Wilkinson Microwave Anisotropy Probe (WMAP) spacecraft functions as the sole interface between (1) the spacecraft and its instrument subsystem and (2) ground operations equipment. This software includes a command-decoding and -distribution system, a telemetry/data-handling system, and a data-storage-and-playback system. This software performs onboard processing of attitude sensor data and generates commands for attitude-control actuators in a closed-loop fashion. It also processes stored commands and monitors health and safety functions for the spacecraft and its instrument subsystems. The basic functionality of this software is the same of that of the older C&DH software of the Rossi X-Ray Timing Explorer (RXTE) spacecraft, the main difference being the addition of the attitude-control functionality. Previously, the C&DH and attitude-control computations were performed by different processors because a single RXTE processor did not have enough processing power. The WMAP spacecraft includes a more-powerful processor capable of performing both computations.

A space radiation shielding model of the Martian radiation environment experiment (MARIE)

NASA Technical Reports Server (NTRS)

Atwell, W.; Saganti, P.; Cucinotta, F. A.; Zeitlin, C. J.

2004-01-01

The 2001 Mars Odyssey spacecraft was launched towards Mars on April 7, 2001. Onboard the spacecraft is the Martian radiation environment experiment (MARIE), which is designed to measure the background radiation environment due to galactic cosmic rays (GCR) and solar protons in the 20-500 MeV/n energy range. We present an approach for developing a space radiation-shielding model of the spacecraft that includes the MARIE instrument in the current mapping phase orientation. A discussion is presented describing the development and methodology used to construct the shielding model. For a given GCR model environment, using the current MARIE shielding model and the high-energy particle transport codes, dose rate values are compared with MARIE measurements during the early mapping phase in Mars orbit. The results show good agreement between the model calculations and the MARIE measurements as presented for the March 2002 dataset. c2003 COSPAR. Published by Elsevier Ltd. All rights reserved.

A space radiation shielding model of the Martian radiationenvironment experiment (MARIE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Atwell, William; Saganti, Premkumar; Cucinotta, Francis A.

2004-12-01

The 2001 Mars Odyssey spacecraft was launched towards Mars on April 7, 2001. On board the spacecraft is the Martian radiation environment experiment (MARIE), which is designed to measure the background radiation environment due to galactic cosmic rays (GCR) and solar protons in the 20 500 MeV/n energy range. We present an approach for developing a space radiation-shielding model of the spacecraft that includes the MARIE instrument in the current mapping phase orientation. A discussion is presented describing the development and methodology used to construct the shielding model. For a given GCR model environment, using the current MARIE shielding modelmore » and the high-energy particle transport codes, dose rate values are compared with MARIE measurements during the early mapping phase in Mars orbit. The results show good agreement between the model calculations and the MARIE measurements as presented for the March 2002 dataset.« less

An Overview of the Juno Mission to Jupiter

NASA Technical Reports Server (NTRS)

Grammier, Richard S.

2006-01-01

Arriving in orbit around the planet Jupiter in 2016 after a five-year journey, the Juno spacecraft will begin a one-year investigation of the gas giant in order to understand its origin and evolution by determining its water abundance and constraining its core mass. In addition, Juno will map the planet's magnetic and gravitational fields, map its atmosphere, and explore the three-dimensional structure of Jupiter's polar magnetosphere and auroras. Juno will discriminate among different models for giant planet formation. These investigations will be conducted over the course of thirty-two 11-day elliptical polar orbits of the planet. The orbits are designed to avoid Jupiter's highest radiation regions. The spacecraft is a spinning, solar-powered system carrying a complement of eight science instruments for conducting the investigations. The spacecraft systems and instruments take advantage of significant design and operational heritage from previous space missions.

Outer planet entry probe system study. Volume 2: Supporting technical studies

NASA Technical Reports Server (NTRS)

1972-01-01

The environment, science investigations, and general mission analysis considerations are given first. These data are followed by discussions of the studies pertaining to the planets Jupiter, Saturn, Uranus, and Neptune. Except for Neptune, each planet discussion is divided into two parts: (1) parametric activities and (2) probe definition for that planet, or the application of a given probe for that planet. The Neptune discussion is limited to parametrics in the area of science and mission analysis. Each of the probe system definitions consists of system and subsystem details including telecommunications, data handling, power pyrotechnics, attitude control, structures, propulsion, thermal control, and probe to spacecraft integration. The first configuration is discussed in detail and the subsequent configuration discussions are limited to the differences. Finally, the hardware availability to support a probe system and commonality of science, missions, and subsystems for use at the various planets are considered.

An exemplar-familiarity model predicts short-term and long-term probe recognition across diverse forms of memory search.

PubMed

Nosofsky, Robert M; Cox, Gregory E; Cao, Rui; Shiffrin, Richard M

2014-11-01

Experiments were conducted to test a modern exemplar-familiarity model on its ability to account for both short-term and long-term probe recognition within the same memory-search paradigm. Also, making connections to the literature on attention and visual search, the model was used to interpret differences in probe-recognition performance across diverse conditions that manipulated relations between targets and foils across trials. Subjects saw lists of from 1 to 16 items followed by a single item recognition probe. In a varied-mapping condition, targets and foils could switch roles across trials; in a consistent-mapping condition, targets and foils never switched roles; and in an all-new condition, on each trial a completely new set of items formed the memory set. In the varied-mapping and all-new conditions, mean correct response times (RTs) and error proportions were curvilinear increasing functions of memory set size, with the RT results closely resembling ones from hybrid visual-memory search experiments reported by Wolfe (2012). In the consistent-mapping condition, new-probe RTs were invariant with set size, whereas old-probe RTs increased slightly with increasing study-test lag. With appropriate choice of psychologically interpretable free parameters, the model accounted well for the complete set of results. The work provides support for the hypothesis that a common set of processes involving exemplar-based familiarity may govern long-term and short-term probe recognition across wide varieties of memory- search conditions. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Focal overlap gating in velocity map imaging to achieve high signal-to-noise ratio in photo-ion pump-probe experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shivaram, Niranjan; Champenois, Elio G.; Cryan, James P.

We demonstrate a technique in velocity map imaging (VMI) that allows spatial gating of the laser focal overlap region in time resolved pump-probe experiments. This significantly enhances signal-to-noise ratio by eliminating background signal arising outside the region of spatial overlap of pump and probe beams. This enhancement is achieved by tilting the laser beams with respect to the surface of the VMI electrodes which creates a gradient in flight time for particles born at different points along the beam. By suitably pulsing our microchannel plate detector, we can select particles born only where the laser beams overlap. Furthermore, this spatialmore » gating in velocity map imaging can benefit nearly all photo-ion pump-probe VMI experiments especially when extreme-ultraviolet light or X-rays are involved which produce large background signals on their own.« less

Focal overlap gating in velocity map imaging to achieve high signal-to-noise ratio in photo-ion pump-probe experiments

DOE PAGES

Shivaram, Niranjan; Champenois, Elio G.; Cryan, James P.; ...

2016-12-19

We demonstrate a technique in velocity map imaging (VMI) that allows spatial gating of the laser focal overlap region in time resolved pump-probe experiments. This significantly enhances signal-to-noise ratio by eliminating background signal arising outside the region of spatial overlap of pump and probe beams. This enhancement is achieved by tilting the laser beams with respect to the surface of the VMI electrodes which creates a gradient in flight time for particles born at different points along the beam. By suitably pulsing our microchannel plate detector, we can select particles born only where the laser beams overlap. Furthermore, this spatialmore » gating in velocity map imaging can benefit nearly all photo-ion pump-probe VMI experiments especially when extreme-ultraviolet light or X-rays are involved which produce large background signals on their own.« less

Numerical Simulations of Spacecraft Charging: Selected Applications

NASA Astrophysics Data System (ADS)

Moulton, J. D.; Delzanno, G. L.; Meierbachtol, C.; Svyatskiy, D.; Vernon, L.; Borovsky, J.; Thomsen, M. F.

2016-12-01

The electrical charging of spacecraft due to bombarding charged particles affects their performance and operation. We study this charging using CPIC, a particle-in-cell code specifically designed for studying plasma-material interactions. CPIC is based on multi-block curvilinear meshes, resulting in near-optimal computational performance while maintaining geometric accuracy. It is interfaced to a mesh generator that creates a computational mesh conforming to complex objects like a spacecraft. Relevant plasma parameters can be imported from the SHIELDS framework (currently under development at LANL), which simulates geomagnetic storms and substorms in the Earth's magnetosphere. Selected physics results will be presented, together with an overview of the code. The physics results include spacecraft-charging simulations with geometry representative of the Van Allen Probes spacecraft, focusing on the conditions that can lead to significant spacecraft charging events. Second, results from a recent study that investigates the conditions for which a high-power (>keV) electron beam could be emitted from a magnetospheric spacecraft will be presented. The latter study proposes a spacecraft-charging mitigation strategy based on the plasma contactor technology that might allow beam experiments to operate in the low-density magnetosphere. High-power electron beams could be used for instance to establish magnetic-field-line connectivity between ionosphere and magnetosphere and help solving long-standing questions in ionospheric/magnetospheric physics.

Enhanced Characterization of Microorganisms in the Spacecraft Environment

NASA Technical Reports Server (NTRS)

Cruz, Patricia; Stetzenbach, Linda D.

2004-01-01

Spacecraft such as the International Space Station (ISS) and the space shuttles are enclosed environments where crewmembers may spend long periods of time. Currently, crewmembers spend approximately a period of 6 months in the ISS. It is known that these prolonged stays in space may result in weakening of the immune system. Therefore, exposure to opportunistic pathogens or high concentrations of environmental microorganisms may compromise the health of the crew. The detection of biocontaminants in spacecraft environments utilizes culture-based methodology, omitting greater than 90% of all microorganisms including pathogens such as Legionella and Cryptosporidium. Culturable bacteria and fungi have been the only allergens studied; the more potent allergens, such as those from dust mites, have never been tested for in spacecraft environments. In addition, no attempts have been made to monitor microbial toxins in spacecrafts. The present study utilized quantitative polymerase chain reaction (QPCR) as a novel approach for monitoring microorganisms in the spacecraft environment. QPCR is a molecular biology technique that does not rely on the physiological state of the organisms for identification, thereby enabling detection of both culturable and non-culturable organisms. In this project, specific molecular primers and probes were utilized for the detection and quantitation of two fungi of concern in indoor environments, Aspergillus fumigatus and Stachybotrys chartarum. These organisms were selected because of the availability of PCR primers and probes, and to establish the sample processing and analysis methodology that may be employed with additional organisms. Purification methods and QPCR assays were optimized for the detection of these organisms in air, surface, and water; and sample processing and analysis protocols were developed. Preliminary validation of these protocols was conducted in the laboratory with air, surface, and water samples seeded with known concentrations of the target organisms. Additional studies were conducted with bulk materials (HEPA filter pleats and particulate found on the filter screen) obtained from the ISS.

Van Allen Probes Observations of Second Harmonic Poloidal Standing Alfvén Waves

NASA Astrophysics Data System (ADS)

Takahashi, Kazue; Oimatsu, Satoshi; Nosé, Masahito; Min, Kyungguk; Claudepierre, Seth G.; Chan, Anthony; Wygant, John; Kim, Hyomin

2018-01-01

Long-lasting second-harmonic poloidal standing Alfvén waves (P2 waves) were observed by the twin Van Allen Probes (Radiation Belt Storm Probes, or RBSP) spacecraft in the noon sector of the plasmasphere, when the spacecraft were close to the magnetic equator and had a small azimuthal separation. Oscillations of proton fluxes at the wave frequency (˜10 mHz) were also observed in the energy (W) range 50-300 keV. Using the unique RBSP orbital configuration, we determined the phase delay of magnetic field perturbations between the spacecraft with a 2nπ ambiguity. We then used finite gyroradius effects seen in the proton flux oscillations to remove the ambiguity and found that the waves were propagating westward with an azimuthal wave number (m) of ˜-200. The phase of the proton flux oscillations relative to the radial component of the wave magnetic field progresses with W, crossing 0 (northward moving protons) or 180° (southward moving protons) at W ˜ 120 keV. This feature is explained by drift-bounce resonance (mωd ˜ ωb) of ˜120 keV protons with the waves, where ωd and ωb are the proton drift and bounce frequencies. At lower energies, the proton phase space density (FH+) exhibits a bump-on-tail structure with ∂FH+/∂W>0 occurring in the 1-10 keV energy range. This FH+ is unstable and can excite P2 waves through bounce resonance (ω ˜ ωb), where ω is the wave frequency.

Krikalev dismantles probe-and-cone docking mechanism (StM) in the Progress M-53 (18P)

NASA Image and Video Library

2005-06-19

ISS011-E-09204 (19 June 2005) --- Cosmonaut Sergei K. Krikalev, Expedition 11 commander representing Russia's Federal Space Agency, dismantles the probe-and-cone docking mechanism in the Progress 18 spacecraft. The Progress docked to the aft port of the Zvezda Service Module of the International Space Station (ISS) at 7:42 p.m. (CDT) as the Station flew approximately 225 statute miles, above a point near Beijing, China.

The Comet Radar Explorer Mission

NASA Astrophysics Data System (ADS)

Asphaug, Erik; Belton, Mike; Bockelee-Morvan, Dominique; Chesley, Steve; Delbo, Marco; Farnham, Tony; Gim, Yonggyu; Grimm, Robert; Herique, Alain; Kofman, Wlodek; Oberst, Juergen; Orosei, Roberto; Piqueux, Sylvain; Plaut, Jeff; Robinson, Mark; Sava, Paul; Heggy, Essam; Kurth, William; Scheeres, Dan; Denevi, Brett; Turtle, Elizabeth; Weissman, Paul

2014-11-01

Missions to cometary nuclei have revealed major geological surprises: (1) Global scale layers - do these persist through to the interior? Are they a record of primary accretion? (2) Smooth regions - are they landslides originating on the surface? Are they cryovolcanic? (3) Pits - are they impact craters or sublimation pits, or rooted in the interior? Unambiguous answers to these and other questions can be obtained by high definition 3D radar reflection imaging (RRI) of internal structure. RRI can answer many of the great unknowns in planetary science: How do primitive bodies accrete? Are cometary nuclei mostly ice? What drives their spectacular activity and evolution? The Comet Radar Explorer (CORE) mission will image the detailed internal structure of the nucleus of 10P/Tempel 2. This ~16 x 8 x 7 km Jupiter Family Comet (JFC), or its parent body, originated in the outer planets region possibly millions of years before planet formation. CORE arrives post-perihelion and observes the comet’s waning activity from safe distance. Once the nucleus is largely dormant, the spacecraft enters a ~20-km dedicated Radar Mapping Orbit (RMO). The exacting design of the RRI experiment and the precise navigation of RMO will achieve a highly focused 3D radar reflection image of internal structure, to tens of meters resolution, and tomographic images of velocity and attenuation to hundreds of meters resolution, tied to the gravity model and shape. Visible imagers will produce maps of the surface morphology, albedo, color, texture, and photometric response, and images for navigation and shape determination. The cameras will also monitor the structure and dynamics of the coma, and its dusty jets, allowing their correlation in 3D with deep interior structures and surface features. Repeated global high-resolution thermal images will probe the near-surface layers heated by the Sun. Derived maps of thermal inertia will be correlated with the radar boundary response, and photometry and texture, probing surface materials attainable by future robotic excavation missions. Thermal images will reveal areas of sublimation cooling around vents and pits, and the secular response of the outer meters as the nucleus moves farther from the Sun.

Separation Anxiety Over for Deep Impact

NASA Image and Video Library

2005-07-04

This image of NASA Deep Impact impactor probe was taken by the mission mother ship, or flyby spacecraft, after the two separated at 11:07 p.m. Pacific time, July 2 2:07 a.m. Eastern time, July 3, 2005.

To probe a core

NASA Astrophysics Data System (ADS)

2017-04-01

Hidden under many kilometres of silicate mantle material, the cores of Earth and other planets are hard to investigate. The Psyche spacecraft, designed to visit a metal body that may be a core stripped of its mantle, could bring a close-up view.

KSC-04PD-1087

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- A Press Site camera, 3.3 miles from Space Launch Complex 2 on Vandenberg AFB, Calif., captures the climb downrange of the Delta II carrying the Gravity Probe B spacecraft. Liftoff occurred at 9:57:24 a.m. PDT.

Low-energy ballistic lunar transfers

NASA Astrophysics Data System (ADS)

Parker, Jeffrey S.

A systematic method is developed that uses dynamical systems theory to model, analyze, and construct low-energy ballistic lunar transfers (BLTs). It has been found that low-energy BLTs may be produced by intersecting the stable manifold of an unstable Earth-Moon three-body orbit with the Earth. A spacecraft following such a trajectory is only required to perform a single maneuver, namely, the Trans-Lunar Injection maneuver, in order to complete the transfer. After the Trans-Lunar Injection maneuver, the spacecraft follows an entirely ballistic trajectory that asymptotically approaches and arrives at the target lunar three-body orbit. Because these orbit transfers require no orbit insertion maneuver at the three-body orbit, the transfers may be used to send spacecraft 25--40% more massive than spacecraft sent to the same orbits via conventional, direct transfers. From the targeted three-body orbits, the spacecraft may transfer to nearly any region within the Earth-Moon system, including any location on the surface of the Moon. The systematic methods developed in this research allow low-energy BLTs to be characterized by six parameters. It has been found that BLTs exist in families, where a family of BLTs consists of transfers whose parameters vary in a continuous fashion from one end of the family to the other. The families are easily identified and studied using a BLT State Space Map (BLT Map). The present research studies BLT Maps and has surveyed a wide variety of BLTs that exist in the observed families. It has been found that many types of BLTs may be constructed between 185-km low Earth parking orbits and lunar three-body orbits that require less than 3.27 km/s and fewer than 120 days of transfer time. Under certain conditions, BLTs may be constructed that require less than 3.2 km/s and fewer than 100 days of transfer time. It has been found that BLTs may implement LEO parking orbits with nearly any combination of altitude and inclination; they may depart from their LEO parking orbits nearly any day of each month; and they may target a variety of different classes of unstable Earth-Moon three-body orbits. Finally, studies are provided that address how low-energy transfers impact the design of spacecraft systems and how BLT Maps may be implemented as pragmatic tools in the design of practical lunar missions.

Highly sensitive mode mapping of whispering-gallery modes by scanning thermocouple-probe microscopy.

PubMed

Klein, Angela E; Schmidt, Carsten; Liebsch, Mattes; Janunts, Norik; Dobynde, Mikhail; Tünnermann, Andreas; Pertsch, Thomas

2014-03-01

We propose a method for mapping optical near-fields with the help of a thermocouple scanning-probe microscope tip. As the tip scans the sample surface, its apex is heated by light absorption, generating a thermovoltage. The thermovoltage map represents the intensity distribution of light at the sample surface. The measurement technique has been employed to map optical whispering-gallery modes in fused silica microdisk resonators operating at near-infrared wavelengths. The method could potentially be employed for near-field imaging of a variety of systems in the near-infrared and visible spectral range.

Employees lower Cassini's upper experiment module and base onto a work stand in the PHSF

NASA Technical Reports Server (NTRS)

1997-01-01

Employees in the Payload Hazardous Servicing Facility (PHSF) lower the upper experiment module and base of the Cassini orbiter onto a work stand during prelaunch processing, testing and integration work in that facility. The Cassini orbiter and Huygens probe being processed at KSC are the two primary components of the Cassini spacecraft, which will be launched on a Titan IVB/Centaur expendable launch vehicle from Cape Canaveral Air Station. Cassini will explore Saturn, its rings and moons for four years. The Huygens probe, designed and developed for the European Space Agency (ESA), will be deployed from the orbiter to study the clouds, atmosphere and surface of Saturn's largest moon, Titan. The orbiter was designed and assembled at NASA's Jet Propulsion Laboratory in California. Following postflight inspections, integration of the 12 science instruments not already installed on the orbiter will be completed. Then, the parabolic high-gain antenna and the propulsion module will be mated to the orbiter, followed by the Huygens probe, which will complete spacecraft integration. The Cassini mission is targeted for an Oct. 6 launch to begin its 6.7-year journey to the Saturnian system. Arrival at the planet is expected to occur around July 1, 2004.

Update on the Fire (solar probe) mission study

NASA Technical Reports Server (NTRS)

Jones, W. Veron; Forman, Miriam A.

1995-01-01

Since mid-1994 the U.S. and Russia have been studying the technical feasibility of a joint solar probe mission as part of the 'Fire and Ice' concept to explore close to the Sun, and Pluto, together. In the current concept of the 'Fire' mission, separate spacecraft built by each country would be launched together, fly by Jupiter to shed orbital angular momentum and achieve a solar polar orbit, and arrive 3.6 years later at 4 and 10 R(sub s). The Fire mission would measure basic parameters of the modes of energy and momentum flow and transfer to the coronal plasma that are not observable remotely. Specifically, measurement of magnetic fields, waves, suprathermal particles, and critical features of the plasma particle composition and distribution function would be made from 4 to 30 R(sub s) where the solar wind is known to be accelerated. In addition, the Fire spacecraft should image coronal structures unambiguously and relate the underlying and flown-through structures to plasma characteristics measured in situ. Each country is developing a backup plan to pursue the solar probe objectives alone if the other side is unable to carry out its mission.