50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Apollo 11 Astronaut Neil Armstrong speaks during a celebration dinner at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Ohio Senator John Glenn sits in the orbiter Columbia's flight deck

NASA Technical Reports Server (NTRS)

1998-01-01

Ohio Senator John Glenn, at left, enjoys a tour of the flight deck in the orbiter Columbia with Astronaut Stephen Oswald at the Orbiter Processing Facility 3 at Kennedy Space Center. Senator Glenn arrived at KSC on Jan. 20 to tour KSC operational areas and to view the launch of STS-89 later this week. Glenn, who made history in 1962 as the first American to orbit the Earth, completing three orbits in a five-hour flight aboard Friendship 7, will fly his second space mission aboard Space Shuttle Discovery this October. Glenn is retiring from the Senate at the end of this year and will be a payload specialist aboard STS-95.

Autonomous Navigation Improvements for High-Earth Orbiters Using GPS

NASA Technical Reports Server (NTRS)

Long, Anne; Kelbel, David; Lee, Taesul; Garrison, James; Carpenter, J. Russell; Bauer, F. (Technical Monitor)

2000-01-01

The Goddard Space Flight Center is currently developing autonomous navigation systems for satellites in high-Earth orbits where acquisition of the GPS signals is severely limited This paper discusses autonomous navigation improvements for high-Earth orbiters and assesses projected navigation performance for these satellites using Global Positioning System (GPS) Standard Positioning Service (SPS) measurements. Navigation performance is evaluated as a function of signal acquisition threshold, measurement errors, and dynamic modeling errors using realistic GPS signal strength and user antenna models. These analyses indicate that an autonomous navigation position accuracy of better than 30 meters root-mean-square (RMS) can be achieved for high-Earth orbiting satellites using a GPS receiver with a very stable oscillator. This accuracy improves to better than 15 meters RMS if the GPS receiver's signal acquisition threshold can be reduced by 5 dB-Hertz to track weaker signals.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

NASA Administrator Charles Bolden answers a question from the press during a briefing at Ohio State University on Monday, Feb. 20, 2012, in Columbus, Ohio. Today marks the 50th anniversary of Glenn's historic flight. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn talks on stage during a celebration dinner at The Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Controllability of Large SEP for Earth Orbit Raising

NASA Technical Reports Server (NTRS)

Woodcock, Gordon

2004-01-01

A six-degree-of-freedom (6DOF) simulation was constructed and exercised for a large solar electric propulsion (SEP) vehicle operating in low Earth orbit Nominal power was 500 kWe, with the large array sizes implied. Controllability issues, including gravity gradient, roll maneuvering for Sun tracking, and flexible arrays, and flight control methods, were investigated. Initial findings are that a SEP vehicle of this size is controllable and could be used for orbit raising of heavy payloads.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn poses for a portrait shortly after doing live television interviews from the Ohio State University Union building on Monday, Feb. 20, 2012, in Columbus, Ohio. Today marks the 50th anniversary of his historic flight. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn, left, and NASA Administrator Charles Bolden speak to guest at NASA's Future Forum at Ohio State University on Monday, Feb. 20, 2012, in Columbus, Ohio. Today marks the 50th anniversary of Glenn's historic flight. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn and his wife Annie listen to speakers during a reception at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn and his wife Annie talk during a celebration dinner at The Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Earth-Mars transfers through Moon Distant Retrograde Orbits

NASA Astrophysics Data System (ADS)

Conte, Davide; Di Carlo, Marilena; Ho, Koki; Spencer, David B.; Vasile, Massimiliano

2018-02-01

This paper focuses on the trajectory design which is relevant for missions that would exploit the use of asteroid mining in stable cis-lunar orbits to facilitate deep space missions, specifically human Mars exploration. Assuming that a refueling "gas station" is present at a given lunar Distant Retrograde Orbit (DRO), ways of departing from the Earth to Mars via that DRO are analyzed. Thus, the analysis and results presented in this paper add a new cis-lunar departure orbit for Earth-Mars missions. Porkchop plots depicting the required C3 at launch, v∞ at arrival, Time of Flight (TOF), and total Δ V for various DRO departure and Mars arrival dates are created and compared with results obtained for low Δ V Low Earth Orbit (LEO) to Mars trajectories. The results show that propellant-optimal trajectories from LEO to Mars through a DRO have higher overall mission Δ V due to the additional stop at the DRO. However, they have lower Initial Mass in LEO (IMLEO) and thus lower gear ratio as well as lower TOF than direct LEO to Mars transfers. This results in a lower overall spacecraft dry mass that needs to be launched into space from Earth's surface.

Multi-spacecraft observations of ICMEs propagating beyond Earth orbit during MSL/RAD flight and surface phases

NASA Astrophysics Data System (ADS)

von Forstner, J.; Guo, J.; Wimmer-Schweingruber, R. F.; Hassler, D.; Temmer, M.; Vrsnak, B.; Čalogović, J.; Dumbovic, M.; Lohf, H.; Appel, J. K.; Heber, B.; Steigies, C. T.; Zeitlin, C.; Ehresmann, B.; Jian, L. K.; Boehm, E.; Boettcher, S. I.; Burmeister, S.; Martin-Garcia, C.; Brinza, D. E.; Posner, A.; Reitz, G.; Matthiae, D.; Rafkin, S. C.; weigle, G., II; Cucinotta, F.

2017-12-01

The propagation of interplanetary coronal mass ejections (ICMEs) between Earth's orbit (1 AU) and Mars ( 1.5 AU) has been studied with their propagation speed estimated from both measurements and simulations. The enhancement of the magnetic fields related to ICMEs and their shock fronts cause so-called Forbush decreases, which can be detected as a reduction of galactic cosmic rays measured on-ground or on a spacecraft. We have used galactic cosmic ray (GCR) data from in-situ measurements at Earth, from both STEREO A and B as well as the GCR measurement by the Radiation Assessment Detector (RAD) instrument onboard Mars Science Laboratory (MSL) on the surface of Mars as well as during its flight to Mars in 2011-2012. A set of ICME events has been selected during the periods when Earth (or STEREO A or B) and MSL locations were nearly aligned on the same side of the Sun in the ecliptic plane (so-called opposition phase). Such lineups allow us to estimate the ICMEs' transit times between 1 AU and the MSL location by estimating the delay time of the corresponding Forbush decreases measured at each location. We investigate the evolution of their propagation speeds after passing Earth's orbit and find that the deceleration of ICMEs due to their interaction with the ambient solar wind continues beyond 1 AU. The results are compared to simulation data obtained from two CME propagation models, namely the Drag-Based Model (DBM) and the WSA-ENLIL plus cone model.

Acquisition/expulsion system for earth orbital propulsion system study. Volume 4: Flight test article

NASA Technical Reports Server (NTRS)

1973-01-01

Two orbital test plans were prepared to verify one of the passive cryogenic storage tank/feedline candidate designs. One plan considered the orbital test article to be launched as a dedicated payload using an Atlas F burner launching configuration. The second plan proposed to launch the orbital test article as a secondary payload on the Titan E/Centaur proof flight. The secondary payload concept was pursued until January 1973, when work to build the hardware for this phase of the contract was terminated for lack of a sponsor for the flight. The dedicated payload launched on an Atlas F is described.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn, left, and NASA Administrator Charles Bolden address questions from the press during a briefing at Ohio State University on Monday, Feb. 20, 2012, in Columbus, Ohio. Today marks the 50th anniversary of Glenn's historic flight. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn and his wife Annie take the stage during a celebration dinner at The Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn's wife Annie listens to an interviewers question during a celebration dinner at The Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

EURECA orbits above the Earth's surface prior to STS-57 OV-105 RMS capture

NASA Technical Reports Server (NTRS)

1993-01-01

Backdropped against open ocean waters, the European Retrievable Carrier (EURECA) spacecraft, with solar array (SA) panels folded flat against its sides, approaches Endeavour, Orbiter Vehicle (OV) 105, on flight day five. Later, the remote manipulator system (RMS) end effector was used to 'capture' the spacecraft. After ten days in Earth orbit, the crew returned to Earth, bringing EURECA home.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn and NASA Deputy Administrator Lori Garver pose for a photograph during a celebration dinner at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Ohio State University student Joanna Fedeli interviews Sen. John Glenn and his wife Annie during a celebration dinner at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

"Night" scene of the STS-5 Columbia in orbit over the earth

NASA Image and Video Library

1982-11-17

S82-39796 (11-16 Nov. 1982) --- A ?night? scene of the STS-5 space shuttle Columbia in orbit over Earth?s glowing horizon was captured by an astronaut crew member aiming a 70mm handheld camera through the aft windows of the flight deck. The aft section of the cargo bay contains two closed protective shields for satellites which were deployed on the flight. The nearest ?cradle? or shield houses the Satellite Business System?s (SBS-3) spacecraft and is visible in this frame while the Telesta Canada ANIK C-3 shield is out of view. The vertical stabilizer, illuminated by the sun, is flanked by two orbital maneuvering system (OMS) pods. Photo credit: NASA

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn, left, and Apollo 11 Astronaut Neil Armstrong are seen prior to the start of a dinner at Ohio State University that honored the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Sen. John Glenn's wife Annie, right, and NASA Deputy Administrator Lori Garver pose for a photograph during a celebration dinner at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Low-Earth orbit satellite servicing economics

NASA Technical Reports Server (NTRS)

Davis, R. F.; Cepollina, F. J.

1982-01-01

Servicing economics of low Earth orbit satellites were studied. The following topics are examined: the economic importance of the repair missions; comparison of mission cost as opposed to satellite modulation transfer functions over a 10 year period; the effect of satellite flight rate change due to changes in satellite failure rate; estimated satellite cost reduction with shuttle operation projects from the 1960's to the 1970's; design objectives of the multimission modular spacecraft; and the economic importance of the repair mission.

Earth orbital operations supporting manned interplanetary missions

NASA Astrophysics Data System (ADS)

Sherwood, Brent; Buddington, Patricia A.; Whittaker, William L.

The orbital operations required to accumulate, assemble, test, verify, maintain, and launch complex manned space systems on interplanetary missions from earth orbit are as vital as the flight hardware itself. Vast numbers of orbital crew are neither necessary nor desirable for accomplishing the required tasks. A suite of robotic techniques under human supervisory control, relying on sensors, software and manipulators either currently emergent or already applied in terrestrial settings, can make the job tractable. The mission vehicle becomes largely self-assembling, using its own rigid aerobrake as a work platform. The Space Station, having been used as a laboratory testbed and to house an assembly crew of four, is not dominated by the process. A feasible development schedule, if begun soon, could emplace orbital support technologies for exploration missions in time for a 2004 first interplanetary launch.

Earth orbital operations supporting manned interplanetary missions

NASA Technical Reports Server (NTRS)

Sherwood, Brent; Buddington, Patricia A.; Whittaker, William L.

1989-01-01

The orbital operations required to accumulate, assemble, test, verify, maintain, and launch complex manned space systems on interplanetary missions from earth orbit are as vital as the flight hardware itself. Vast numbers of orbital crew are neither necessary nor desirable for accomplishing the required tasks. A suite of robotic techniques under human supervisory control, relying on sensors, software and manipulators either currently emergent or already applied in terrestrial settings, can make the job tractable. The mission vehicle becomes largely self-assembling, using its own rigid aerobrake as a work platform. The Space Station, having been used as a laboratory testbed and to house an assembly crew of four, is not dominated by the process. A feasible development schedule, if begun soon, could emplace orbital support technologies for exploration missions in time for a 2004 first interplanetary launch.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

NASA Administrator Charles Bolden, seated right, and Sen. John Glenn address questions from the press during a briefing at Ohio State University as John Glenn's wife Annie Glenn, seated in red, looks on Monday, Feb. 20, 2012, in Columbus, Ohio. Today marks the 50th anniversary of Glenn's historic flight. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Autonomous Mars ascent and orbit rendezvous for earth return missions

NASA Technical Reports Server (NTRS)

Edwards, H. C.; Balmanno, W. F.; Cruz, Manuel I.; Ilgen, Marc R.

1991-01-01

The details of tha assessment of autonomous Mars ascent and orbit rendezvous for earth return missions are presented. Analyses addressing navigation system assessments, trajectory planning, targeting approaches, flight control guidance strategies, and performance sensitivities are included. Tradeoffs in the analysis and design process are discussed.

Returning an Entire Near-Earth Asteroid in Support of Human Exploration Beyond Low-Earth Orbit

NASA Technical Reports Server (NTRS)

Brophy, John R.; Friedman, Louis

2012-01-01

This paper describes the results of a study into the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The feasibility of such an asteroid retrieval mission hinges on finding an overlap between the smallest NEAs that could be reasonably discovered and characterized and the largest NEAs that could be captured and transported in a reasonable flight time. This overlap appears to be centered on NEAs roughly 7 m in diameter corresponding to masses in the range of 250,000 kg to 1,000,000 kg. The study concluded that it would be possible to return a approx.500,000-kg NEA to high lunar orbit by around 2025. The feasibility is enabled by three key developments: the ability to discover and characterize an adequate number of sufficiently small near-Earth asteroids for capture and return; the ability to implement sufficiently powerful solar electric propulsion systems to enable transportation of the captured NEA; and the proposed human presence in cislunar space in the 2020s enabling exploration and exploitation of the returned NEA. Placing a 500-t asteroid in high lunar orbit would provide a unique, meaningful, and affordable destination for astronaut crews in the next decade. This disruptive capability would have a positive impact on a wide range of the nation's human space exploration interests. It would provide a high-value target in cislunar space that would require a human presence to take full advantage of this new resource. It would offer an affordable path to providing operational experience with astronauts working around and with a NEA that could feed forward to much longer duration human missions to larger NEAs in deep space. It represents a new synergy between robotic and human missions in which robotic spacecraft would retrieve significant quantities of valuable resources for exploitation by astronaut crews to enable human exploration farther out into

EURECA 11 months in orbit: Initial post flight investigation results

NASA Technical Reports Server (NTRS)

Dover, Alan; Aceti, Roberto; Drolshagen, Gerhard

1995-01-01

This paper gives a brief overview of the European free flying spacecraft 'EURECA' and the initial post flight investigations following its retrieval in June 1993. EURECA was in low earth orbit for 11 months commencing in August 1992, and is the first spacecraft to be retrieved and returned to Earth since the recovery of LDEF. The primary mission objective of EURECA was the investigation of materials and fluids in a very low micro-gravity environment. In addition other experiments were conducted in space science, technology and space environment disciplines. The European Space Agency (ESA) has taken the initiative in conducting a detailed post-flight investigation to ensure the full exploitation of this unique opportunity.

LANDSAT-2 launch and flight activation. Launch through orbit 50 and orbit adjust operation. [telemetry data processing

NASA Technical Reports Server (NTRS)

1975-01-01

The results of the analysis conducted on the telemetry data from the prelaunch, launch, and flight activation phases of LANDSAT-2 spacecraft are presented according to subsystems and interrelationships that exist between subsystems. Subsystem characteristics are included along with the flight evaluation results. Flight data are compared to baseline data established at the 20 C plateau during thermal vacuum testing of the spacecraft. Evaluation guidelines are derived from the specifications developed from the LANDSAT program objectives: (1) acquisition of multispectral images of the surface of the earth; and (2) use of the LANDSAT-2 receiving, frequency translating, and transmitting equipment as a relay system to gather data from fixed earth-based sensor platforms which are operated by individual investigators. Data are presented on the first 50 orbits of the spacecraft.

The O/OREOS Mission - Astrobiology in Low Earth Orbit. [Astrobiology in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Ehrenfreund, P.; Ricco, A. J.; Squires, D.; Kitts, C.; Agasid, E.; Bramall, N.; Bryson, K.; Chittenden, J.; Conley, C.; Cook, A.;

Flight Performance Handbook for Orbital Operations: Orbital Mechanics and Astrodynamics Formulae, Theorems, Techniques, and Applications

NASA Technical Reports Server (NTRS)

Ambrosio, Alphonso; Blitzer, Leon; Conte, S.D.; Cooper, Donald H.; Dergarabedian, P.; Dethlefsen, D.G.; Lunn, Richard L.; Ireland, Richard O.; Jensen, Arnold A.; Kang, Garfield;

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

Captain Mark Kelly, commander of the space shuttle Endeavour’s final mission and husband of retired U.S. Representative Gabrielle Giffords, gives the keynote address during a celebration dinner at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Introducing Earth's Orbital Eccentricity

ERIC Educational Resources Information Center

Oostra, Benjamin

2015-01-01

Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

Low Earth Orbiter: Terminal

NASA Technical Reports Server (NTRS)

Kremer, Steven E.; Bundick, Steven N.

1999-01-01

In response to the current government budgetary environment that requires the National Aeronautics and Space Administration (NASA) to do more with less, NASA/Goddard Space Flight Center's Wallops Flight Facility has developed and implemented a class of ground stations known as a Low Earth Orbiter-Terminal (LEO-T). This development thus provides a low-cost autonomous ground tracking service for NASA's customers. More importantly, this accomplishment provides a commercial source to spacecraft customers around the world to purchase directly from the company awarded the NASA contract to build these systems. A few years ago, NASA was driven to provide more ground station capacity for spacecraft telemetry, tracking, and command (TT&C) services with a decreasing budget. NASA also made a decision to develop many smaller, cheaper satellites rather than a few large spacecraft as done in the past. In addition, university class missions were being driven to provide their own TT&C services due to the increasing load on the NASA ground-tracking network. NASA's solution for this ever increasing load was to use the existing large aperture systems to support those missions requiring that level of performance and to support the remainder of the missions with the autonomous LEO-T systems. The LEO-T antenna system is a smaller, cheaper, and fully autonomous unstaffed system that can operate without the existing NASA support infrastructure. The LEO-T provides a low-cost, reliable space communications service to the expanding number of low-earth orbiting missions around the world. The system is also fostering developments that improve cost-effectiveness of autonomous-class capabilities for NASA and commercial space use. NASA has installed three LEO-T systems. One station is at the University of Puerto Rico, the second system is installed at the Poker Flat Research Range near Fairbanks, Alaska, and the third system is installed at NASA's Wallops Flight Facility in Virginia. This paper

Space shuttle orbiter test flight series

NASA Technical Reports Server (NTRS)

Garrett, D.; Gordon, R.; Jackson, R. B.

1977-01-01

The proposed studies on the space shuttle orbiter test taxi runs and captive flight tests were set forth. The orbiter test flights, the approach and landing tests (ALT), and the ground vibration tests were cited. Free flight plans, the space shuttle ALT crews, and 747 carrier aircraft crew were considered.

Planning Orbiter Flights

NASA Technical Reports Server (NTRS)

Harris, H. M.; Bergam, M. J.; Kim, S. L.; Smith, E. A.

1987-01-01

Shuttle Mission Design and Operations Software (SMDOS) assists in design and operation of missions involving spacecraft in low orbits around Earth by providing orbital and graphics information. SMDOS performs following five functions: display two world and two polar maps or any user-defined window 5 degrees high in latitude by 5 degrees wide in longitude in one of eight standard projections; designate Earth sites by points or polygon shapes; plot spacecraft ground track with 1-min demarcation lines; display, by means of different colors, availability of Tracking and Data Relay Satellite to Shuttle; and calculate available times and orbits to view particular site, and corresponding look angles. SMDOS written in Laboratory Micro-systems FORTH (1979 standard)

An algorithm for enhanced formation flying of satellites in low earth orbit

NASA Astrophysics Data System (ADS)

Folta, David C.; Quinn, David A.

1998-01-01

With scientific objectives for Earth observation programs becoming more ambitious and spacecraft becoming more autonomous, the need for innovative technical approaches on the feasibility of achieving and maintaining formations of spacecraft has come to the forefront. The trend to develop small low-cost spacecraft has led many scientists to recognize the advantage of flying several spacecraft in formation to achieve the correlated instrument measurements formerly possible only by flying many instruments on a single large platform. Yet, formation flying imposes additional complications on orbit maintenance, especially when each spacecraft has its own orbit requirements. However, advances in automation and technology proposed by the Goddard Space Flight Center (GSFC) allow more of the burden in maneuver planning and execution to be placed onboard the spacecraft, mitigating some of the associated operational concerns. The purpose of this paper is to present GSFC's Guidance, Navigation, and Control Center's (GNCC) algorithm for Formation Flying of the low earth orbiting spacecraft that is part of the New Millennium Program (NMP). This system will be implemented as a close-loop flight code onboard the NMP Earth Orbiter-1 (EO-1) spacecraft. Results of this development can be used to determine the appropriateness of formation flying for a particular case as well as operational impacts. Simulation results using this algorithm integrated in an autonomous `fuzzy logic' control system called AutoCon™ are presented.

Orbiter Auxiliary Power Unit Flight Support Plan

NASA Technical Reports Server (NTRS)

Guirl, Robert; Munroe, James; Scott, Walter

1990-01-01

This paper discussed the development of an integrated Orbiter Auxiliary Power Unit (APU) and Improved APU (IAPU) Flight Suuport Plan. The plan identifies hardware requirements for continued support of flight activities for the Space Shuttle Orbiter fleet. Each Orbiter vehicle has three APUs that provide power to the hydraulic system for flight control surface actuation, engine gimbaling, landing gear deployment, braking, and steering. The APUs contain hardware that has been found over the course of development and flight history to have operating time and on-vehicle exposure time limits. These APUs will be replaced by IAPUs with enhanced operating lives on a vehicle-by-vehicle basis during scheduled Orbiter modification periods. This Flight Support Plan is used by program management, engineering, logistics, contracts, and procurement groups to establish optimum use of available hardware and replacement quantities and delivery requirements for APUs until vehicle modifications and incorporation of IAPUs. Changes to the flight manifest and program delays are evaluated relative to their impact on hardware availability.

Guidance Scheme for Modulation of Drag Devices to Enable Return from Low Earth Orbit

NASA Technical Reports Server (NTRS)

Dutta, Soumyo; Bowes, Angela L.; Cianciolo, Alicia D.; Glass, Christopher E.; Powell, Richard W.

2017-01-01

Passive drag devices provide opportunities to return payloads from low Earth orbits quickly without using onboard propulsive systems to de-orbit the spacecraft. However, one potential disadvantage of such systems has been the lack of landing accuracy. Drag modulation or changing the shape of the drag device during flight offer a way to control the de-orbit trajectory and target a specific landing location. This paper discusses a candidate passive drag based system, called Exo-brake, as well as efforts to model the dynamics of the vehicle as it de-orbits and guidance schemes used to control the trajectory. Such systems can enable quick return of payloads from low Earth orbit assets like the International Space Station without the use of large re-entry cargo capsules or propulsive systems.

Introduction to orbital flight planning (1)

NASA Technical Reports Server (NTRS)

Blackwell, H. E. (Editor); Davis, E. L.; Dell, D. D.

1981-01-01

This workbook is designed for students interested in space flight planning, who after training, may serve as flight planning aides. Routine flight planning activities requiring engineering-type calculations and analysis are covered. Practice exercises and brief instructions are given for the programming and use of the hand calculator as well as the calculation of position and velocity in the orbital plane. Calculation of relative orbital position is also covered with emphasis upon celestial coordinates and time measurement.

Orbit Determination Error Analysis Results for the Triana Sun-Earth L2 Libration Point Mission

NASA Technical Reports Server (NTRS)

Marr, G.

2003-01-01

Using the NASA Goddard Space Flight Center's Orbit Determination Error Analysis System (ODEAS), orbit determination error analysis results are presented for all phases of the Triana Sun-Earth L1 libration point mission and for the science data collection phase of a future Sun-Earth L2 libration point mission. The Triana spacecraft was nominally to be released by the Space Shuttle in a low Earth orbit, and this analysis focuses on that scenario. From the release orbit a transfer trajectory insertion (TTI) maneuver performed using a solid stage would increase the velocity be approximately 3.1 km/sec sending Triana on a direct trajectory to its mission orbit. The Triana mission orbit is a Sun-Earth L1 Lissajous orbit with a Sun-Earth-vehicle (SEV) angle between 4.0 and 15.0 degrees, which would be achieved after a Lissajous orbit insertion (LOI) maneuver at approximately launch plus 6 months. Because Triana was to be launched by the Space Shuttle, TTI could potentially occur over a 16 orbit range from low Earth orbit. This analysis was performed assuming TTI was performed from a low Earth orbit with an inclination of 28.5 degrees and assuming support from a combination of three Deep Space Network (DSN) stations, Goldstone, Canberra, and Madrid and four commercial Universal Space Network (USN) stations, Alaska, Hawaii, Perth, and Santiago. These ground stations would provide coherent two-way range and range rate tracking data usable for orbit determination. Larger range and range rate errors were assumed for the USN stations. Nominally, DSN support would end at TTI+144 hours assuming there were no USN problems. Post-TTI coverage for a range of TTI longitudes for a given nominal trajectory case were analyzed. The orbit determination error analysis after the first correction maneuver would be generally applicable to any libration point mission utilizing a direct trajectory.

Combining MHD Airbreathing and Fusion Rocket Propulsion for Earth-to-Orbit Flight

NASA Astrophysics Data System (ADS)

Froning, H. D.; Miley, G. H.; Luo, Nie; Yang, Yang; Momota, H.; Burton, E.

2005-02-01

Previous studies have shown that Single-State-to-Orbit (SSTO) vehicle propellant can be reduced by Magnets-Hydro-Dynamic (MHD) processes that minimize airbreathing propulsion losses and propellant consumption during atmospheric flight. Similarly additional reduction in SSTO propellant is enabled by Inertial Electrostatic Confinement (IEC) fusion, whose more energetic reactions reduce rocket propellant needs. MHD airbreathing propulsion during an SSTO vehicle's initial atmospheric flight phase and IEC fusion propulsion during its final exo-atmospheric flight phase is therefore being explored. Accomplished work is not yet sufficient for claiming such a vehicle's feasibility. But takeoff and propellant mass for an MHD airbreathing and IEC fusion vehicle could be as much as 25 and 40 percent less than one with ordinary airbreathing and IEC fusion; and as much as 50 and 70 percent less than SSTO takeoff and propellant mass with MHD airbreathing and chemical rocket propulsion. Thus this unusual combined cycle engine shows great promise for performance gains beyond contemporary combined-cycle airbreathing engines.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

NASA Administrator Charles Bolden surprises Sen. John Glenn, both seated on stage, with a live downlink from International Space Station Expedition 30 crew members Don Pettit, left on screen, Andre Kuipers, and Dan Burbank, right on screen, while Director of the NASA Glenn Research Center Ray Lugo moderates, during NASA's Future Forum at The Ohio State University on Monday, Feb. 20, 2012, in Columbus, Ohio. Monday marked the 50th anniversary of Glenn's historic flight as the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

The NASA Earth Science Flight Program: an update

NASA Astrophysics Data System (ADS)

Neeck, Steven P.

2015-10-01

Earth's changing environment impacts every aspect of life on our planet and climate change has profound implications on society. Studying Earth as a single complex system is essential to understanding the causes and consequences of climate change and other global environmental concerns. NASA's Earth Science Division (ESD) shapes an interdisciplinary view of Earth, exploring interactions among the atmosphere, oceans, ice sheets, land surface interior, and life itself. This enables scientists to measure global and climate changes and to inform decisions by government, other organizations, and people in the United States and around the world. The data collected and results generated are accessible to other agencies and organizations to improve the products and services they provide, including air quality indices, disaster prediction and response, agricultural yield projections, and aviation safety. ESD's Flight Program provides the space based observing systems and infrastructure for mission operations and scientific data processing and distribution that support NASA's Earth science research and modeling activities. The Flight Program currently has 21 operating Earth observing space missions, including the recently launched Global Precipitation Measurement (GPM) mission, the Orbiting Carbon Observatory-2 (OCO-2), the Soil Moisture Active Passive (SMAP) mission, and the International Space Station (ISS) RapidSCAT and Cloud-Aerosol Transport System (CATS) instruments. The ESD has 22 more missions and instruments planned for launch over the next decade. These include first and second tier missions from the 2007 Earth Science Decadal Survey, Climate Continuity missions and selected instruments to assure availability of key climate data sets, operational missions to ensure sustained land imaging provided by the Landsat system, and small-sized competitively selected orbital missions and instrument missions of opportunity belonging to the Earth Venture (EV) Program. Some

The International Space Station: A Low-Earth Orbit (LEO) Test Bed for Advancements in Space and Environmental Medicine

NASA Technical Reports Server (NTRS)

Ruttley, Tara M.; Robinson, Julie A.

2010-01-01

Ground-based space analog projects such as the NASA Extreme Environment Mission Operations (NEEMO) can be valuable test beds for evaluation of experimental design and hardware feasibility before actually being implemented on orbit. The International Space Station (ISS) is an closed-system laboratory that orbits 240 miles above the Earth, and is the ultimate extreme environment. Its inhabitants spend hours performing research that spans from fluid physics to human physiology, yielding results that have implications for Earth-based improvements in medicine and health, as well as those that will help facilitate the mitigation of risks to the human body associated with exploration-class space missions. ISS health and medical experiments focus on pre-flight and in-flight prevention, in-flight treatment, and postflight recovery of health problems associated with space flight. Such experiments include those on enhanced medical monitoring, bone and muscle loss prevention, cardiovascular health, immunology, radiation and behavior. Lessons learned from ISS experiments may not only be applicable to other extreme environments that face similar capability limitations, but also serve to enhance standards of care for everyday use on Earth.

Analytical investigation of the dynamics of tethered constellations in Earth orbit, phase 2

NASA Technical Reports Server (NTRS)

Lorenzini, Enrico C.; Gullahorn, Gordon E.; Cosmo, Mario L.; Estes, Robert D.; Grossi, Mario D.

1994-01-01

This final report covers nine years of research on future tether applications and on the actual flights of the Small Expendable Deployment System (SEDS). Topics covered include: (1) a description of numerical codes used to simulate the orbital and attitude dynamics of tethered systems during station keeping and deployment maneuvers; (2) a comparison of various tethered system simulators; (3) dynamics analysis, conceptual design, potential applications and propagation of disturbances and isolation from noise of a variable gravity/microgravity laboratory tethered to the Space Station; (4) stability of a tethered space centrifuge; (5) various proposed two-dimensional tethered structures for low Earth orbit for use as planar array antennas; (6) tethered high gain antennas; (7) numerical calculation of the electromagnetic wave field on the Earth's surface on an electrodynamically tethered satellite; (8) reentry of tethered capsules; (9) deployment dynamics of SEDS-1; (10) analysis of SEDS-1 flight data; and (11) dynamics and control of SEDS-2.

Orbital Sciences Pegasus XL Flight Simulation

NASA Image and Video Library

2007-02-28

At Vandenberg Air Force Base in California, the Orbital Sciences Pegasus XL rocket undergoes its second flight simulation. The rocket is the launch vehicle for NASA's Aeronomy of Ice in the Mesosphere, or AIM, spacecraft. AIM is the seventh Small Explorers mission under NASA's Explorer Program. The program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics. The AIM spacecraft will fly three instruments designed to study polar mesospheric clouds located at the edge of space, 50 miles above the Earth's surface in the coldest part of the planet's atmosphere. The mission's primary goal is to explain why these clouds form and what has caused them to become brighter and more numerous and appear at lower latitudes in recent years. AIM's results will provide the basis for the study of long-term variability in the mesospheric climate and its relationship to global climate change. AIM is scheduled to be mated to the Pegasus XL during the second week of April, after which final inspections will be conducted. Launch is scheduled for April 25.

Orbital Sciences Pegasus XL Flight Simulation

NASA Image and Video Library

2007-02-28

At Vandenberg Air Force Base in California, a worker monitors the Orbital Sciences Pegasus XL rocket after a second flight simulation. The rocket is the launch vehicle for NASA's Aeronomy of Ice in the Mesosphere, or AIM, spacecraft. AIM is the seventh Small Explorers mission under NASA's Explorer Program. The program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics. The AIM spacecraft will fly three instruments designed to study polar mesospheric clouds located at the edge of space, 50 miles above the Earth's surface in the coldest part of the planet's atmosphere. The mission's primary goal is to explain why these clouds form and what has caused them to become brighter and more numerous and appear at lower latitudes in recent years. AIM's results will provide the basis for the study of long-term variability in the mesospheric climate and its relationship to global climate change. AIM is scheduled to be mated to the Pegasus XL during the second week of April, after which final inspections will be conducted. Launch is scheduled for April 25.

Manual control aspects of orbital flight

NASA Technical Reports Server (NTRS)

Brody, Adam R.

1990-01-01

Studies of spacecraft rendezvous and docking operations began in the Gemini program in preparation for the two dockings required to send a crew to the moon and return them safely to Earth. However, the goal of getting to the moon before the end of the decade was of greater concern than mission optimization so little or no time or money was expended in researching human factors implications of operational aspects such as braking gates or control modes. Also, with sixteen operational dockings over a six year period (12 Apollo, 3 Skylab, and 1 ASTP) in the United States space program, economies of scale were not yet available to justify extensive research into decreasing the time or fuel necessary for a successful docking. With an operational space station era approaching in which orbital maneuvering vehicle (OMV), orbital transfer vehicle (OTV), shuttle orbiter, and other traffic will play a major role, a concerted research effort now could help avoid many potential problems later in addition to increasing safety, fuel economy, and productivity. A knowledge of manual control capabilities associated with piloted spaceflight could help save a life if the operational flight envelope can be safely enlarged to include faster dockings that currently envisioned. For example, current and future research is designed to acquire the appropriate information.

STS-106 Orbit 2 Flight Team

NASA Image and Video Library

2000-09-14

JSC2000-06244 (September 2000)--- Flight director Jeff Hanley, front center, and the fifty-odd flight controllers making up the ISS Orbit 2 Team pose for their group portrait in the ISS Flight Control Room of Houston's Mission Control Center.

Simulation of interference between Earth stations and Earth-orbiting satellites

NASA Technical Reports Server (NTRS)

Bishop, D. F.

1994-01-01

It is often desirable to determine the potential for radio frequency interference between earth stations and orbiting spacecraft. This information can be used to select frequencies for radio systems to avoid interference or it can be used to determine if coordination between radio systems is necessary. A model is developed that will determine the statistics of interference between earth stations and elliptical orbiting spacecraft. The model uses orbital dynamics, detailed antenna patterns, and spectral characteristics to obtain accurate levels of interference at the victim receiver. The model is programmed into a computer simulation to obtain long-term statistics of interference. Two specific examples are shown to demonstrate the model. The first example is a simulation of interference from a fixed-satellite earth station to an orbiting scatterometer receiver. The second example is a simulation of interference from earth-exploration satellites to a deep-space earth station.

The orbital distribution of Near-Earth Objects inside Earth's orbit

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Ngo, Henry; Gladman, Brett

2012-01-01

Canada's Near-Earth Object Surveillance Satellite (NEOSSat), set to launch in early 2012, will search for and track Near-Earth Objects (NEOs), tuning its search to best detect objects with a < 1.0 AU. In order to construct an optimal pointing strategy for NEOSSat, we needed more detailed information in the a < 1.0 AU region than the best current model (Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J.M., Levison, H.F., Michel, P., Metcalfe, T.S. [2002]. Icarus 156, 399-433) provides. We present here the NEOSSat-1.0 NEO orbital distribution model with larger statistics that permit finer resolution and less uncertainty, especially in the a < 1.0 AU region. We find that Amors = 30.1 ± 0.8%, Apollos = 63.3 ± 0.4%, Atens = 5.0 ± 0.3%, Atiras (0.718 < Q < 0.983 AU) = 1.38 ± 0.04%, and Vatiras (0.307 < Q < 0.718 AU) = 0.22 ± 0.03% of the steady-state NEO population. Vatiras are a previously undiscussed NEO population clearly defined in our integrations, whose orbits lie completely interior to that of Venus. Our integrations also uncovered the unexpected production of retrograde orbits from main-belt asteroid sources; this retrograde NEA population makes up ≃0.1% of the steady-state NEO population. The relative NEO impact rate onto Mercury, Venus, and Earth, as well as the normalized distribution of impact speeds, was calculated from the NEOSSat-1.0 orbital model under the assumption of a steady-state. The new model predicts a slightly higher Mercury impact flux.

Preliminary Results of the GPS Flight Experiment on the High Earth Orbit AMSAT-OSCAR 40 Spacecraft

NASA Technical Reports Server (NTRS)

Moreau, Michael C.; Bauer, Frank H.; Carpenter, J. Russell; Davis, Edward P.; Davis, George W.; Jackson, Larry A.

2002-01-01

The GPS flight experiment on the High Earth Orbit (HEO) AMSAT-OSCAR 40 (AO-40) spacecraft was activated for a period of approximately six weeks between 25 September and 2 November, 2001, and the initial results have exciting implications for using GPS as a low-cost orbit determination sensor for future HEO missions. AO-40, an amateur radio satellite launched November 16, 2000, is currently in a low inclination, 1000 by 58,800 km altitude orbit. Although the GPS receiver was not initialized in any way, it regularly returned GPS observations from points all around the orbit. Raw signal to noise levels as high as 9 AMUs (Trimble Amplitude Measurement Units) or approximately 48 dB-Hz have been recorded at apogee, when the spacecraft was close to 60,000 km in altitude. On several occasions when the receiver was below the GPS constellation (below 20,000 krn altitude), observations were reported for GPS satellites tracked through side lobe transmissions. Although the receiver has not returned any point solutions, there has been at least one occasion when four satellites were tracked simultaneously, and this short arc of data was used to compute point solutions after the fact. These results are encouraging, especially considering the spacecraft is currently in a spin-stabilized attitude mode that narrows the effective field of view of the receiving antennas and adversely affects GPS tracking. Already AO-40 has demonstrated the feasibility of recording GPS observations in HEO using an unaided receiver. Furthermore, it is providing important information about the characteristics of GPS signals received by a spacecraft in a HEO, which has long been of interest to many in the GPS community. Based on the data returned so far, the tracking performance is expected to improve when the spacecraft is transitioned to a three axis stabilized, nadir pointing attitude in Summer, 2002.

Applicability of the control configured design approach to advanced earth orbital transportation systems

NASA Technical Reports Server (NTRS)

Hepler, A. K.; Zeck, H.; Walker, W. H.; Shafer, D. E.

1978-01-01

The applicability of the control configured design approach (CCV) to advanced earth orbital transportation systems was studied. The baseline system investigated was fully reusable vertical take-off/horizontal landing single-stage-to-orbit vehicle and had mission requirements similar to the space shuttle orbiter. Technical analyses were made to determine aerodynamic, flight control and subsystem design characteristics. Figures of merit were assessed on vehicle dry weight and orbital payload. The results indicated that the major parameters for CCV designs are hypersonic trim, aft center of gravity, and control surface heating. Optimized CCV designs can be controllable and provide substantial payload gains over conventional non-CCV design vertical take-off vehicles.

Low-Earth-Orbit and Geosynchronous-Earth-Orbit Testing of 80 Ah Batteries under Real-time Profiles

NASA Technical Reports Server (NTRS)

Staniewicz, Robert J.; Willson, John; Briscoe, J. Douglas; Rao, Gopalakrishna M.

2004-01-01

This viewgraph presentation gives an update on test results from two 16 cell batteries, one in a simulated Low Earth Orbit (LEO) environment and the other in simulated Geosynchronous Earth Orbit (GEO) environment. The tests measured how voltage and capacity are affected over time by thermal cycling.

NASA Advanced Concepts Office, Earth-To-Orbit Team Design Process and Tools

NASA Technical Reports Server (NTRS)

Waters, Eric D.; Garcia, Jessica; Beers, Benjamin; Philips, Alan; Holt, James B.; Threet, Grady E., Jr.

2013-01-01

The Earth to Orbit (ETO) Team of the Advanced Concepts Office (ACO) at NASA Marshal Space Flight Center (MSFC) is considered the preeminent group to go to for prephase A and phase A concept definition. The ACO team has been at the forefront of a multitude of launch vehicle studies determining the future direction of the Agency as a whole due, in part, to their rapid turnaround time in analyzing concepts and their ability to cover broad trade spaces of vehicles in that limited timeframe. Each completed vehicle concept includes a full mass breakdown of each vehicle to tertiary subsystem components, along with a vehicle trajectory analysis to determine optimized payload delivery to specified orbital parameters, flight environments, and delta v capability. Additionally, a structural analysis of the vehicle based on material properties and geometries is performed as well as an analysis to determine the flight loads based on the trajectory outputs. As mentioned, the ACO Earth to Orbit Team prides themselves on their rapid turnaround time and often need to fulfill customer requests within limited schedule or little advanced notice. Due to working in this fast paced environment, the ETO team has developed some finely honed skills and methods to maximize the delivery capability to meet their customer needs. This paper will describe the interfaces between the 3 primary disciplines used in the design process; weights and sizing, trajectory, and structural analysis, as well as the approach each discipline employs to streamline their particular piece of the design process.

Aeroheating Analysis for the Mars Reconnaissance Orbiter with Comparison to Flight Data

NASA Technical Reports Server (NTRS)

Liechty, Derek S.

2007-01-01

The aeroheating environment of the Mars Reconnaissance Orbiter (MRO) has been analyzed using the direct simulation Monte Carlo and free-molecular techniques. The results of these analyses were used to develop an aeroheating database to be used for the preflight planning and the in-flight operations support for the aerobraking phase of the MRO mission. The aeroheating predictions calculated for the MRO include the heat transfer coefficient (CH) over a range of angles-of-attack, sideslip angles, and number densities. The effects of flow chemistry, surface temperature, and surface grid resolution were also investigated to determine the aeroheating database uncertainties. Flight heat flux data has been calculated from surface temperature sensor data returned to Earth from the MRO in orbit around Mars during the aerobraking phase of its mission. The heat flux data have been compared to the aeroheating database and agree favorably.

Near Earth Asteroids- Prospection, Orbit Modification and Mining

NASA Astrophysics Data System (ADS)

Grandl, W.; Bazso, A.

2014-04-01

thrust and specific impulse to move the huge masses of the asteroids. Such a propulsion system could be the Bussard Fusion System, also known as the quiet-electricdischarge (QED) engine. It uses electrostatic fusion devices to generate electrical power. The fuel consists of Deuterium and Helium3 that are fusing to Helium4 plus protons releasing 18.3 MeV of energy per reaction. The charged protons escape from the confinement; their kinetic energy can be converted to electricity or be used directly as a plasma beam for generating thrust. For the reaction a specific energy of 3.5x1014 Joule/kg can be computed, i.e. orders-ofmagnitude higher than for any existing propulsion system. As an example we take the Asteroid with the designation 2008 EV5. It is classified as an Aten group asteroid with a mean diameter of 450 meters and belongs to spectral type S (stony asteroids). Our mass estimate (using a bulk density of 3 g/cm^3) is 1.4x1011 kg. To transfer 2008 EV5 to an Earth-like orbit the energy required is estimated to be in the order of 2.8x1018 Joule. This is the difference in Kepler energy between the NEA's current orbit and the Earth's orbit around the sun. Using the Bussard Fusion System the amount of fuel would be approx. 8000 kg of Helium3. To move an asteroid by remote control the authors propose to design unmanned space tugs which are propelled by Bussard Fusion Engines. A pair of space tugs is docked to each asteroid using drilling anchors. The fusion engines of the tugs then apply the thrust forces for the maneuvers. The first tug, which carries the main fuel quantity, applies the primary force for the orbital maneuvers. The second one adjust the flight track by short engine thrusts.

Low Earth Orbit Raider (LER) winged air launch vehicle concept

NASA Technical Reports Server (NTRS)

Feaux, Karl; Jordan, William; Killough, Graham; Miller, Robert; Plunk, Vonn

1989-01-01

The need to launch small payloads into low earth orbit has increased dramatically during the past several years. The Low Earth orbit Raider (LER) is an answer to this need. The LER is an air-launched, winged vehicle designed to carry a 1500 pound payload into a 250 nautical mile orbit. The LER is launched from the back of a 747-100B at 35,000 feet and a Mach number of 0.8. Three staged solid propellant motors offer safe ground and flight handling, reliable operation, and decreased fabrication cost. The wing provides lift for 747 separation and during the first stage burn. Also, aerodynamic controls are provided to simplify first stage maneuvers. The air-launch concept offers many advantages to the consumer compared to conventional methods. Launching at 35,000 feet lowers atmospheric drag and other loads on the vehicle considerably. Since the 747 is a mobile launch pad, flexibility in orbit selection and launch time is unparalleled. Even polar orbits are accessible with a decreased payload. Most importantly, the LER launch service can come to the customer, satellites and experiments need not be transported to ground based launch facilities. The LER is designed to offer increased consumer freedom at a lower cost over existing launch systems. Simplistic design emphasizing reliability at low cost allows for the light payloads of the LER.

50th Anniversary First American to Orbit Earth

NASA Image and Video Library

2012-02-20

The Ohio State University President E. Gordon Gee, left, Apollo 11 Astronaut Neil Armstrong, 2nd from left, Former space shuttle astronaut and former Under Secretary of the Air Force Dr. Ron Sega, and Captain Mark Kelly, commander of the space shuttle Endeavour’s final mission and husband of retired U.S. Representative Gabrielle Giffords, right, talk prior to a reception at Ohio State University honoring the 50th anniversary of John Glenn's historic flight aboard Friendship 7 Monday, Feb. 20, 2012, in Columbus, Ohio. Glenn was the first American to orbit Earth. Photo Credit: (NASA/Bill Ingalls)

Flight dynamics facility operational orbit determination support for the ocean topography experiment

NASA Technical Reports Server (NTRS)

Bolvin, D. T.; Schanzle, A. F.; Samii, M. V.; Doll, C. E.

1991-01-01

The Ocean Topography Experiment (TOPEX/POSEIDON) mission is designed to determine the topography of the Earth's sea surface across a 3 yr period, beginning with launch in June 1992. The Goddard Space Flight Center Dynamics Facility has the capability to operationally receive and process Tracking and Data Relay Satellite System (TDRSS) tracking data. Because these data will be used to support orbit determination (OD) aspects of the TOPEX mission, the Dynamics Facility was designated to perform TOPEX operational OD. The scientific data require stringent OD accuracy in navigating the TOPEX spacecraft. The OD accuracy requirements fall into two categories: (1) on orbit free flight; and (2) maneuver. The maneuver OD accuracy requirements are of two types; premaneuver planning and postmaneuver evaluation. Analysis using the Orbit Determination Error Analysis System (ODEAS) covariance software has shown that, during the first postlaunch mission phase of the TOPEX mission, some postmaneuver evaluation OD accuracy requirements cannot be met. ODEAS results also show that the most difficult requirements to meet are those that determine the change in the components of velocity for postmaneuver evaluation.

A high voltage electrical power system for low Earth orbit applications

NASA Technical Reports Server (NTRS)

Lanier, J. R., Jr.; Bush, J. R., Jr.

1984-01-01

The results of testing a high voltage electrical power system (EPS) breadboard using high voltage power processing equipment developed at Marshall Space Flight Center and Ni-Cd batteries are discussed. These test results are used to extrapolate to an efficient, reliable, high capacity EPS for near term low Earth orbit, high power applications. EPS efficiencies, figures of merit, and battery reliability with a battery protection and reconditioning circuit are presented.

Abort Options for Human Lunar Missions between Earth Orbit and Lunar Vicinity

NASA Technical Reports Server (NTRS)

Condon, Gerald L.; Senent, Juan S.; Llama, Eduardo Garcia

2005-01-01

Apollo mission design emphasized operational flexibility that supported premature return to Earth. However, that design was tailored to use expendable hardware for short expeditions to low-latitude sites and cannot be applied directly to an evolutionary program requiring long stay times at arbitrary sites. This work establishes abort performanc e requirements for representative onorbit phases of missions involvin g rendezvous in lunar-orbit, lunar-surface and at the Earth-Moon libr ation point. This study submits reference abort delta-V requirements and other Earth return data (e.g., entry speed, flight path angle) and also examines the effect of abort performance requirements on propul sive capability for selected vehicle configurations.

Orbital Sciences Pegasus XL Flight Simulation

NASA Image and Video Library

2007-02-28

At Vandenberg Air Force Base in California, workers monitor the data produced by the second flight simulation of the Orbital Sciences Pegasus XL rocket. The rocket is the launch vehicle for NASA's Aeronomy of Ice in the Mesosphere, or AIM, spacecraft. AIM is the seventh Small Explorers mission under NASA's Explorer Program. The program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics. The AIM spacecraft will fly three instruments designed to study polar mesospheric clouds located at the edge of space, 50 miles above the Earth's surface in the coldest part of the planet's atmosphere. The mission's primary goal is to explain why these clouds form and what has caused them to become brighter and more numerous and appear at lower latitudes in recent years. AIM's results will provide the basis for the study of long-term variability in the mesospheric climate and its relationship to global climate change. AIM is scheduled to be mated to the Pegasus XL during the second week of April, after which final inspections will be conducted. Launch is scheduled for April 25.

Orbital Sciences Pegasus XL Flight Simulation

NASA Image and Video Library

2007-02-28

At Vandenberg Air Force Base in California, a worker monitors the data produced by the second flight simulation of the Orbital Sciences Pegasus XL rocket. The rocket is the launch vehicle for NASA's Aeronomy of Ice in the Mesosphere, or AIM, spacecraft. AIM is the seventh Small Explorers mission under NASA's Explorer Program. The program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics. The AIM spacecraft will fly three instruments designed to study polar mesospheric clouds located at the edge of space, 50 miles above the Earth's surface in the coldest part of the planet's atmosphere. The mission's primary goal is to explain why these clouds form and what has caused them to become brighter and more numerous and appear at lower latitudes in recent years. AIM's results will provide the basis for the study of long-term variability in the mesospheric climate and its relationship to global climate change. AIM is scheduled to be mated to the Pegasus XL during the second week of April, after which final inspections will be conducted. Launch is scheduled for April 25.

Mission Analysis Program for Solar Electric Propulsion (MAPSEP). Volume 1: Analytical manual for earth orbital MAPSEP

NASA Technical Reports Server (NTRS)

1975-01-01

An introduction to the MAPSEP organization and a detailed analytical description of all models and algorithms are given. These include trajectory and error covariance propagation methods, orbit determination processes, thrust modeling, and trajectory correction (guidance) schemes. Earth orbital MAPSEP contains the capability of analyzing almost any currently projected low thrust mission from low earth orbit to super synchronous altitudes. Furthermore, MAPSEP is sufficiently flexible to incorporate extended dynamic models, alternate mission strategies, and almost any other system requirement imposed by the user. As in the interplanetary version, earth orbital MAPSEP represents a trade-off between precision modeling and computational speed consistent with defining necessary system requirements. It can be used in feasibility studies as well as in flight operational support. Pertinent operational constraints are available both implicitly and explicitly. However, the reader should be warned that because of program complexity, MAPSEP is only as good as the user and will quickly succumb to faulty user inputs.

The Orion Exploration Flight Test Post Flight Solid Particle Flight Environment Inspection and Analysis

NASA Technical Reports Server (NTRS)

Miller, Joshua E.

2016-01-01

Orbital debris in the millimeter size range can pose a hazard to current and planned spacecraft due to the high relative impact speeds in Earth orbit. Fortunately, orbital debris has a relatively short life at lower altitudes due to atmospheric effects; however, at higher altitudes orbital debris can survive much longer and has resulted in a band of high flux around 700 to 1,500 km above the surface of the Earth. While large orbital debris objects are tracked via ground based observation, little information can be gathered about small particles except by returned surfaces, which until the Orion Exploration Flight Test number one (EFT-1), has only been possible for lower altitudes (400 to 500 km). The EFT-1 crew module backshell, which used a porous, ceramic tile system with surface coatings, has been inspected post-flight for potential micrometeoroid and orbital debris (MMOD) damage. This paper describes the pre- and post-flight activities of inspection, identification and analysis of six candidate MMOD impact craters from the EFT-1 mission.

A feasibility study of orbiter flight control experiments

NASA Technical Reports Server (NTRS)

Geissler, W. H.

1978-01-01

The results of a feasibility study of orbiter flight control experiments performed are summarized. Feasibility studies were performed on a group of 14 experiments selected from a candidate list of 35 submitted to the study contractor by the flight control community. Concepts and requirements were developed for the 14 selected experiments and they were ranked on a basis of technical value, feasibility, and cost. It was concluded that all the selected experiments can be considered as potential candidates for the Orbiter Experiment program, which is being formulated for the Orbiter Flight Tests and subsequent operational flights, regardless of the relative ranking established during the study. None of the selected experiments has significant safety implications and the cost of most was estimated to be less than $200K.

Large-payload earth-orbit transportation with electric propulsion

NASA Technical Reports Server (NTRS)

Stearns, J. W.

1976-01-01

Economical unmanned earth orbit transportation for large payloads is evaluated. The high exhaust velocity achievable with electric propulsion is attractive because it minimizes the propellant that must be carried to low earth orbit. Propellant transport is a principal cost item. Electric propulsion subsystems utilizing advanced ion thrusters are compared to magnetoplasmadynamic (MPD) thrust subsystems. For very large payloads, a large lift vehicle is needed to low earth orbit, and argon propellant is required for electric propulsion. Under these circumstances, the MPD thruster is shown to be desirable over the ion thruster for earth orbit transportation.

Earth orbital variations and vertebrate bioevolution

NASA Technical Reports Server (NTRS)

Mclean, Dewey M.

1988-01-01

Cause of the Pleistocene-Holocene transition mammalian extinctions at the end of the last age is the subject of debate between those advocating human predation and climate change. Identification of an ambient air temperature (AAT)-uterine blood flow (UBF) coupling phenomenon supports climate change as a factor in the extinctions, and couples the extinctions to earth orbital variations that drive ice age climatology. The AAT-UBF phenomenon couples mammalian bioevolution directly to climate change via effects of environmental heat upon blood flow to the female uterus and damage to developing embryos. Extinctions were in progress during climatic warming before the Younger Dryas event, and after, at times when the AAT-UBF couple would have been operative; however, impact of a sudden short-term cooling on mammals in the process of adapting to smaller size and relatively larger S/V would have been severe. Variations in earth's orbit, and orbital forcing of atmospheric CO2 concentrations, were causes of the succession of Pleistocene ice ages. Coincidence of mammalian extinctions with terminations of the more intense cold stages links mammalian bioevolution to variations in earth's orbit. Earth orbital variations are a driving source of vertebrate bioevolution.

Orbiter windward surface entry Heating: Post-orbital flight test program update

NASA Technical Reports Server (NTRS)

Harthun, M. H.; Blumer, C. B.; Miller, B. A.

1983-01-01

Correlations of orbiter windward surface entry heating data from the first five flights are presented with emphasis on boundary layer transition and the effects of catalytic recombination. Results show that a single roughness boundary layer transition correlation developed for spherical element trips works well for the orbiter tile system. Also, an engineering approach for predicting heating in nonequilibrium flow conditions shows good agreement with the flight test data in the time period of significant heating. The results of these correlations, when used to predict orbiter heating for a high cross mission, indicate that the thermal protection system on the windward surface will perform successfully in such a mission.

Pre-flight views of orbiter Endeavour on way to launch pad for STS-77

NASA Image and Video Library

1996-05-01

S96-07957 (16 April 1996) --- A road sign points to Launch Pad 39B, the final earthly destination for the Space Shuttle Endeavour and its final stepping stone into space. Endeavour began the slow journey from the Vehicle Assembly Building (VAB) at about 10:00a.m., April 16, 1996, perched atop the Mobile Launcher Platform and carried by the Crawler-Transporter. Upcoming activities at the pad to prepare Endeavour for flight on STS-77 include installation of the payloads in the Orbiter?s payload bay.

Review of Orbiter Flight Boundary Layer Transition Data

NASA Technical Reports Server (NTRS)

Mcginley, Catherine B.; Berry, Scott A.; Kinder, Gerald R.; Barnell, maria; Wang, Kuo C.; Kirk, Benjamin S.

2006-01-01

In support of the Shuttle Return to Flight program, a tool was developed to predict when boundary layer transition would occur on the lower surface of the orbiter during reentry due to the presence of protuberances and cavities in the thermal protection system. This predictive tool was developed based on extensive wind tunnel tests conducted after the loss of the Space Shuttle Columbia. Recognizing that wind tunnels cannot simulate the exact conditions an orbiter encounters as it re-enters the atmosphere, a preliminary attempt was made to use the documented flight related damage and the orbiter transition times, as deduced from flight instrumentation, to calibrate the predictive tool. After flight STS-114, the Boundary Layer Transition Team decided that a more in-depth analysis of the historical flight data was needed to better determine the root causes of the occasional early transition times of some of the past shuttle flights. In this paper we discuss our methodology for the analysis, the various sources of shuttle damage information, the analysis of the flight thermocouple data, and how the results compare to the Boundary Layer Transition prediction tool designed for Return to Flight.

The Effect of Low Earth Orbit Atomic Oxygen Exposure on Phenylphosphine Oxide-Containing Polymers

NASA Technical Reports Server (NTRS)

Connell, John W.

2000-01-01

Thin films of phenylphosphine oxide-containing polymers were exposed to low Earth orbit aboard a space shuttle flight (STS-85) as part of flight experiment designated Evaluation of Space Environment and Effects on Materials (ESEM). This flight experiment was a cooperative effort between the NASA Langley Research Center (LaRC) and the National Space Development Agency of Japan (NASDA). The thin film samples described herein were part of an atomic oxygen exposure experiment (AOE) and were exposed to primarily atomic oxygen (1 X 1019 atoms/cm2). The thin film samples consisted of three phosphine oxide containing polymers (arylene ether, benzimidazole and imide). Based on post-flight analyses using atomic force microscopy, X-ray photoelectron spectroscopy, and weight loss data, it was found that atomic oxygen exposure of these materials efficiently produces a phosphate layer at the surface of the samples. This layer provides a barrier towards further attack by AO. Consequently, these materials do not exhibit linear erosion rates which is in contrast with most organic polymers. Qualitatively, the results obtained from these analyses compare favorably with those obtained from samples exposed to atomic oxygen and or oxygen plasma in ground based exposure experiments. The results of the low Earth orbit atomic oxygen exposure on these materials will be compared with those of ground based exposure to AO.

Deep Reconditioning Testing for near Earth Orbits

NASA Technical Reports Server (NTRS)

Betz, F. E.; Barnes, W. L.

1984-01-01

The problems and benefits of deep reconditioning to near Earth orbit missions with high cycle life and shallow discharge depth requirements is discussed. A simple battery level approach to deep reconditioning of nickel cadmium batteries in near Earth orbit is considered. A test plan was developed to perform deep reconditioning in direct comparison with an alternative trickle charge approach. The results demonstrate that the deep reconditioning procedure described for near Earth orbit application is inferior to the alternative of trickle charging.

Material Density Distribution of Small Debris in Earth Orbit

NASA Technical Reports Server (NTRS)

Krisko, P. H.; Xu, Y.-l.; Opiela, J. N.; Hill, N. M.; Matney, M. J.

2008-01-01

Over 200 spacecraft and rocket body breakups in Earth orbit have populated that regime with debris fragments in the sub-micron through meter size range. Though the largest debris fragments can cause significant collisional damage to active (operational) spacecraft, these are few and trackable by radar. Fragments on the order of a millimeter to a centimeter in size are as yet untrackable. But this smaller debris can result in damage to critical spacecraft systems and, under the worst conditions, fragmenting collision events. Ongoing research at the NASA Orbital Debris Program Office on the sources of these small fragments has focused on the material components of spacecraft and rocket bodies and on breakup event morphology. This has led to fragment material density estimates, and also the beginnings of shape categorizations. To date the NASA Standard Breakup Model has not considered specific material density distinctions of small debris. The basis of small debris in that model is the fourth hypervelocity impact event of the Satellite Orbital Debris Characterization Impact Test (SOCIT) series. This test targeted a flight-ready, U.S. Transit navigation satellite with a solid aluminum sphere impactor. Results in this event yield characteristic length (size) and area-to-mass distributions of fragments smaller than 10 cm in the NASA model. Recent re-analysis of the SOCIT4 small fragment dataset highlighted the material-specific characteristics of metals and non-metals. Concurrent analysis of Space Shuttle in-situ impact data showed a high percentage of aluminum debris in shuttle orbit regions. Both analyses led to the definition of three main on-orbit debris material density categories -low density (< 2 g/cc), medium density (2 to 6 g/cc), and high density (> 6 g/cc). This report considers the above studies in an explicit extension of the NASA Standard Breakup Model where separate material densities for debris are generated and these debris fragments are propagated in

Low Earth orbit communications satellite

NASA Technical Reports Server (NTRS)

Moroney, D.; Lashbrook, D.; Mckibben, B.; Gardener, N.; Rivers, T.; Nottingham, G.; Golden, B.; Barfield, B.; Bruening, J.; Wood, D.

1992-01-01

A current thrust in satellite communication systems considers a low-Earth orbiting constellations of satellites for continuous global coverage. Conceptual design studies have been done at the time of this design project by LORAL Aerospace Corporation under the program name GLOBALSTAR and by Motorola under their IRIDIUM program. This design project concentrates on the spacecraft design of the GLOBALSTAR low-Earth orbiting communication system. Overview information on the program was gained through the Federal Communications Commission licensing request. The GLOBALSTAR system consists of 48 operational satellites positioned in a Walker Delta pattern providing global coverage and redundancy. The operational orbit is 1389 km (750 nmi) altitude with eight planes of six satellites each. The orbital planes are spaced 45 deg., and the spacecraft are separated by 60 deg. within the plane. A Delta 2 launch vehicle is used to carry six spacecraft for orbit establishment. Once in orbit, the spacecraft will utilize code-division multiple access (spread spectrum modulation) for digital relay, voice, and radio determination satellite services (RDSS) yielding position determination with accuracy up to 200 meters.

Aqua Satellite Orbiting Earth Artist Concept

NASA Image and Video Library

2002-05-08

NASA Aqua satellite carries six state-of-the-art instruments in a near-polar low-Earth orbit. Aqua is seen in this artist concept orbiting Earth. The six instruments are the Atmospheric Infrared Sounder (AIRS), the Advanced Microwave Sounding Unit (AMSU-A), the Humidity Sounder for Brazil (HSB), the Advanced Microwave Scanning Radiometer for EOS (AMSR-E), the Moderate Resolution Imaging Spectroradiometer (MODIS), and Clouds and the Earth's Radiant Energy System (CERES). Each has unique characteristics and capabilities, and all six serve together to form a powerful package for Earth observations. http://photojournal.jpl.nasa.gov/catalog/PIA18156

Earth orbiting Sisyphus system study

NASA Technical Reports Server (NTRS)

Jurkevich, I.; Krause, K. W.; Neste, S. L.; Soberman, R. K.

1971-01-01

The feasibility of employing an optical meteoroid detecting system, known as Sisyphus, to measure the near-earth particulates from an earth orbiting vehicle, is considered. A Sisyphus system can discriminate between natural and man-made particles since the system measures orbital characteristics of particles. A Sisyphus system constructed for the Pioneer F/G missions to Jupiter is used as the baseline, and is described. The amount of observing time which can be obtained by a Sisyphus instrument launched into various orbits is determined. Observation time is lost when, (1) the Sun is in or near the field of view, (2) the lighted Earth is in or near the field of view, (3) the instrument is eclipsed by the Earth, and (4) the phase angle measured at the particle between the forward scattering direction and the instrument is less than a certain critical value. The selection of the launch system and the instrument platform with a dedicated, attitude controlled payload package is discussed. Examples of such systems are SATS and SOLRAD 10(C) vehicles, and other possibilities are AVCO Corp. S4 system, the OWL system, and the Delta Payload Experiment Package.

In Flight Performance of a Six Ampere-hour Nickel-cadmium Battery in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Mcdermott, J. K.

1984-01-01

Flight data for 17,000 orbital cycles are reviewed and summarized. The nickel cadmium battery system operated without failure or abnormality. Battery trend analysis used in determining the feasibility of extending mission life is discussed. The life test data for 20% depth of discharge indicates design life requirements would be reached even at a deeper depth of discharge.

Orbital debris and near-Earth environmental management: A chronology

NASA Technical Reports Server (NTRS)

Portree, David S. F.; Loftus, Joseph P., Jr.

1993-01-01

This chronology covers the 32-year history of orbital debris and near-Earth environmental concerns. It tracks near-Earth environmental hazard creation, research, observation, experimentation, management, mitigation, protection, and policy-making, with emphasis on the orbital debris problem. Included are the Project West Ford experiments; Soviet ASAT tests and U.S. Delta upper stage explosions; the Ariane V16 explosion, U.N. treaties pertinent to near-Earth environmental problems, the PARCS tests; space nuclear power issues, the SPS/orbital debris link; Space Shuttle and space station orbital debris issues; the Solwind ASAT test; milestones in theory and modeling the Cosmos 954, Salyut 7, and Skylab reentries; the orbital debris/meteoroid research link; detection system development; orbital debris shielding development; popular culture and orbital debris; Solar Max results; LDEF results; orbital debris issues peculiar to geosynchronous orbit, including reboost policies and the stable plane; seminal papers, reports, and studies; the increasing effects of space activities on astronomy; and growing international awareness of the near-Earth environment.

The Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) List of Near-Earth Asteroids: Identifying Potential Targets for Future Exploration

NASA Astrophysics Data System (ADS)

Abell, Paul; Barbee, B. W.; Mink, R. G.; Adamo, D. R.; Alberding, C. M.; Mazanek, D. D.; Johnson, L. N.; Yeomans, D. K.; Chodas, P. W.; Chamberlin, A. B.; Benner, L. A. M.; Drake, B. G.; Friedensen, V. P.

2012-10-01

Introduction: Much attention has recently been focused on human exploration of near-Earth asteroids (NEAs). Detailed planning for deep space exploration and identification of potential NEA targets for human space flight requires selecting objects from the growing list of known NEAs. NASA therefore initiated the Near-Earth Object Human Space Flight Accessible Target Study (NHATS), which uses dynamical trajectory performance constraints to identify potentially accessible NEAs. Accessibility Criteria: Future NASA human space flight capability is being defined while the Orion Multi-Purpose Crew Vehicle and Space Launch System are under development. Velocity change and mission duration are two of the most critical factors in any human spaceflight endeavor, so the most accessible NEAs tend to be those with orbits similar to Earth’s. To be classified as NHATS-compliant, a NEA must offer at least one round-trip trajectory solution satisfying purposely inclusive constraints, including total mission change in velocity ≤ 12 km/s, mission duration ≤ 450 days (with at least 8 days at the NEA), Earth departure between Jan 1, 2015 and Dec 31, 2040, Earth departure C3 ≤ 60 km2/s2, and Earth return atmospheric entry speed ≤ 12 km/s. Monitoring and Updates: The NHATS list of potentially accessible targets is continuously updated as NEAs are discovered and orbit solutions for known NEAs are improved. The current list of accessible NEAs identified as potentially viable for future human exploration under the NHATS criteria is available to the international community via a website maintained by NASA’s NEO Program Office (http://neo.jpl.nasa.gov/nhats/). This website also lists predicted optical and radar observing opportunities for each NHATS-compliant NEA to facilitate acquisition of follow-up observations. Conclusions: This list of NEAs will be useful for analyzing robotic mission opportunities, identifying optimal round trip human space flight trajectories, and

On-Orbit Constraints Test - Performing Pre-Flight Tests with Flight Hardware, Astronauts and Ground Support Equipment to Assure On-Orbit Success

NASA Technical Reports Server (NTRS)

Haddad, Michael E.

2008-01-01

On-Orbit Constraints Test (OOCT's) refers to mating flight hardware together on the ground before they will be mated on-orbit. The concept seems simple but it can be difficult to perform operations like this on the ground when the flight hardware is being designed to be mated on-orbit in a zero-g and/or vacuum environment of space. Also some of the items are manufactured years apart so how are mating tasks performed on these components if one piece is on-orbit before its mating piece is planned to be built. Both the Internal Vehicular Activity (IVA) and Extra-Vehicular Activity (EVA) OOCT's performed at Kennedy Space Center will be presented in this paper. Details include how OOCT's should mimic on-orbit operational scenarios, a series of photographs will be shown that were taken during OOCT's performed on International Space Station (ISS) flight elements, lessons learned as a result of the OOCT's will be presented and the paper will conclude with possible applications to Moon and Mars Surface operations planned for the Constellation Program.

A Preliminary Data Model for Orbital Flight Dynamics in Shuttle Mission Control

NASA Technical Reports Server (NTRS)

ONeill, John; Shalin, Valerie L.

2000-01-01

The Orbital Flight Dynamics group in Shuttle Mission Control is investigating new user interfaces in a project called RIOTS [RIOTS 2000]. Traditionally, the individual functions of hardware and software guide the design of displays, which results in an aggregated, if not integrated interface. The human work system has then been designed and trained to navigate, operate and integrate the processors and displays. The aim of RIOTS is to reduce the cognitive demands of the flight controllers by redesigning the user interface to support the work of the flight controller. This document supports the RIOTS project by defining a preliminary data model for Orbital Flight Dynamics. Section 2 defines an information-centric perspective. An information-centric approach aims to reduce the cognitive workload of the flight controllers by reducing the need for manual integration of information across processors and displays. Section 3 describes the Orbital Flight Dynamics domain. Section 4 defines the preliminary data model for Orbital Flight Dynamics. Section 5 examines the implications of mapping the data model to Orbital Flight Dynamics current information systems. Two recurring patterns are identified in the Orbital Flight Dynamics work the iteration/rework cycle and the decision-making/information integration/mirroring role relationship. Section 6 identifies new requirements on Orbital Flight Dynamics work and makes recommendations based on changing the information environment, changing the implementation of the data model, and changing the two recurring patterns.

Flight Test Results of the Earth Observing-1 Advanced Land Imager Advanced Land Imager

NASA Astrophysics Data System (ADS)

Mendenhall, Jeffrey A.; Lencioni, Donald E.; Hearn, David R.; Digenis, Constantine J.

2002-09-01

The Advanced Land Imager (ALI) is the primary instrument on the Earth Observing-1 spacecraft (EO-1) and was developed under NASA's New Millennium Program (NMP). The NMP mission objective is to flight-validate advanced technologies that will enable dramatic improvements in performance, cost, mass, and schedule for future, Landsat-like, Earth Science Enterprise instruments. ALI contains a number of innovative features designed to achieve this objective. These include the basic instrument architecture, which employs a push-broom data collection mode, a wide field-of-view optical design, compact multi-spectral detector arrays, non-cryogenic HgCdTe for the short wave infrared bands, silicon carbide optics, and a multi-level solar calibration technique. The sensor includes detector arrays that operate in ten bands, one panchromatic, six VNIR and three SWIR, spanning the range from 0.433 to 2.35 μm. Launched on November 21, 2000, ALI instrument performance was monitored during its first year on orbit using data collected during solar, lunar, stellar, and earth observations. This paper will provide an overview of EO-1 mission activities during this period. Additionally, the on-orbit spatial and radiometric performance of the instrument will be compared to pre-flight measurements and the temporal stability of ALI will be presented.

Shuttle orbiter flash evaporator operational flight test performance

NASA Technical Reports Server (NTRS)

Nason, J. R.; Behrend, A. F., Jr.

1982-01-01

The Flash evaporator System (FES is part of the Shuttle Orbiter Active Thermal Control Subsystem. The FES provides total heat rejection for the vehicle Freon Coolant Loops during ascent and entry and supplementary heat rejection during orbital mission phases. This paper reviews the performance of the FES during the first two Shuttle orbital missions (STS-1 and STS-2). A comparison of actual mission performance against design requirements is presented. Mission profiles (including Freon inlet temperature and feedwater pressure transients), control temperature, and heat load variations are evaluated. Anomalies that occurred during STS-2 are discussed along with the procedures conducted, both in-flight and post-flight, to isolate the causes. Finally, the causes of the anomalies and resulting corrective action taken for STS-3 and subsequent flights are presented.

Orbit Determination (OD) Error Analysis Results for the Triana Sun-Earth L1 Libration Point Mission and for the Fourier Kelvin Stellar Interferometer (FKSI) Sun-Earth L2 Libration Point Mission Concept

NASA Technical Reports Server (NTRS)

Marr, Greg C.

2003-01-01

The Triana spacecraft was designed to be launched by the Space Shuttle. The nominal Triana mission orbit will be a Sun-Earth L1 libration point orbit. Using the NASA Goddard Space Flight Center's Orbit Determination Error Analysis System (ODEAS), orbit determination (OD) error analysis results are presented for all phases of the Triana mission from the first correction maneuver through approximately launch plus 6 months. Results are also presented for the science data collection phase of the Fourier Kelvin Stellar Interferometer Sun-Earth L2 libration point mission concept with momentum unloading thrust perturbations during the tracking arc. The Triana analysis includes extensive analysis of an initial short arc orbit determination solution and results using both Deep Space Network (DSN) and commercial Universal Space Network (USN) statistics. These results could be utilized in support of future Sun-Earth libration point missions.

The O/OREOS mission—Astrobiology in low Earth orbit

NASA Astrophysics Data System (ADS)

Ehrenfreund, P.; Ricco, A. J.; Squires, D.; Kitts, C.; Agasid, E.; Bramall, N.; Bryson, K.; Chittenden, J.; Conley, C.; Cook, A.; Mancinelli, R.; Mattioda, A.; Nicholson, W.; Quinn, R.; Santos, O.; Tahu, G.; Voytek, M.; Beasley, C.; Bica, L.; Diaz-Aguado, M.; Friedericks, C.; Henschke, M.; Landis, D.; Luzzi, E.; Ly, D.; Mai, N.; Minelli, G.; McIntyre, M.; Neumann, M.; Parra, M.; Piccini, M.; Rasay, R.; Ricks, R.; Schooley, A.; Stackpole, E.; Timucin, L.; Yost, B.; Young, A.

2014-01-01

The O/OREOS (Organism/Organic Exposure to Orbital Stresses) nanosatellite is the first science demonstration spacecraft and flight mission of the NASA Astrobiology Small-Payloads Program (ASP). O/OREOS was launched successfully on November 19, 2010, to a high-inclination (72°), 650-km Earth orbit aboard a US Air Force Minotaur IV rocket from Kodiak, Alaska. O/OREOS consists of 3 conjoined cubesat (each 1000 cm3) modules: (i) a control bus; (ii) the Space Environment Survivability of Living Organisms (SESLO) experiment; and (iii) the Space Environment Viability of Organics (SEVO) experiment. Among the innovative aspects of the O/OREOS mission are a real-time analysis of the photostability of organics and biomarkers and the collection of data on the survival and metabolic activity for microorganisms at 3 times during the 6-month mission. We report on the spacecraft characteristics, payload capabilities, and present operational phase and flight data from the O/OREOS mission. The science and technology rationale of O/OREOS supports NASA's scientific exploration program by investigating the local space environment as well as space biology relevant to Moon and Mars missions. It also serves as a precursor for experiments on small satellites, the International Space Station (ISS), future free-flyers and lunar surface exposure facilities.

Mission design for a halo orbiter of the earth

NASA Technical Reports Server (NTRS)

Farquhar, R. W.; Muhonen, D. P.; Richardson, D. L.

1976-01-01

The International Sun-Earth Explorer (ISEE) scientific satellite to be stationed in 1978 in the vicinity of the sun-earth interior libration point to continuously monitor the space between the sun and the earth, including the distant geomagnetic tail is described. Orbit selection considerations for the ISEE-C are discussed along with stationkeeping requirements and fuel-optimal trajectories. Due to the alignment of the interior libration point with the sun as viewed from the earth, it will be necessary to place the satellite into a 'halo orbit' around the libration point, in order to eliminate solar interference with down-link telemetry. Parametric data for transfer trajectories between an earth parking orbit (altitude about 185 km) and a libration-point orbit are presented. It is shown that the insertion magnitude required for placing a satellite into an acceptable halo orbit is rather modest.

Comprehensive Evaluation of Attitude and Orbit Estimation Using Actual Earth Magnetic Field Data

NASA Technical Reports Server (NTRS)

Deutschmann, Julie K.; Bar-Itzhack, Itzhack Y.

2000-01-01

A single, augmented Extended Kalman Filter (EKF), which simultaneously and autonomously estimates spacecraft attitude and orbit has been developed and successfully tested with real magnetometer and gyro data only. Because the earth magnetic field is a function of time and position, and because time is known quite precisely, the differences between the computed and measured magnetic field components, as measured by the magnetometers throughout the entire spacecraft orbit, are a function of both orbit and attitude errors. Thus, conceivably these differences could be used to estimate both orbit and attitude; an observability study validated this assumption. The results of testing the EKF with actual magnetometer and gyro data, from four satellites supported by the NASA Goddard Space Flight Center (GSFC) Guidance, Navigation, and Control Center, are presented and evaluated. They confirm the assumption that a single EKF can estimate both attitude and orbit when using gyros and magnetometers only.

Optimal trajectories for the Aeroassisted Flight Experiment. Part 1: Equations of motion in an Earth-fixed system

NASA Technical Reports Server (NTRS)

Miele, A.; Zhao, Z. G.; Lee, W. Y.

1989-01-01

The determination of optimal trajectories for the aeroassisted flight experiment (AFE) is discussed. The AFE refers to the study of the free flight of an autonomous spacecraft, shuttle-launched and shuttle-recovered. Its purpose is to gather atmospheric entry environmental data for use in designing aeroassisted orbital transfer vehicles (AOTV). It is assumed that: (1) the spacecraft is a particle of constant mass; (2) the Earth is rotating with constant angular velocity; (3) the Earth is an oblate planet, and the gravitational potential depends on both the radial distance and the latitude (harmonics of order higher than four are ignored); and (4) the atmosphere is at rest with respect to the Earth. Under these assumptions, the equations of motion for hypervelocity atmospheric flight (which can be used not only for AFE problems, but also for AOT problems and space shuttle problems) are derived in an Earth-fixed system. Transformation relations are supplied which allow one to pass from quantities computed in an Earth-fixed system to quantities computed in an inertial system, and vice versa.

A Survey Of Earth-Moon Libration Orbits: Stationkeeping Strategies And Intra-Orbit Transfers

NASA Technical Reports Server (NTRS)

Folta, David; Vaughn, Frank

2004-01-01

Cislunar space is a readily accessible region that may well develop into a prime staging area in the effort to colonize space near Earth or to colonize the Moon. While there have been statements made by various NASA programs regarding placement of resources in orbit about the Earth-Moon Lagrangian locations, there is no survey of the total cost associated with attaining and maintaining these unique orbits in an operational fashion. Transfer trajectories between these orbits required for assembly, servicing, and positioning of these resources have not been extensively investigated. These orbits are dynamically similar to those used for the Sun-Earth missions, but differences in governing gravitational ratios and perturbation sources result in unique characteristics. We implement numerical computations using high fidelity models and linear and nonlinear targeting techniques to compute the various maneuver (Delta)V and temporal costs associated with orbits about each of the Earth-Moon Lagrangian locations (L1, L2, L3, L4, and L5). From a dynamical system standpoint, we speak to the nature of these orbits and their stability. We address the cost of transfers between each pair of Lagrangian locations.

Earth-to-Orbit Education Program 'Makes Science Cool'

NASA Technical Reports Server (NTRS)

2002-01-01

In this photograph, Jeff Alden (left) and Justin O'Cornor, two middle school students at Lane Middle School in Portland, Oregon are demonstrating their Earth-to-Orbit (ETO) Design Challenge project at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. Jeff and Justin, who are just a couple of 'typical teens,' have been spending their time tackling some of the same challenges NASA engineers face when designing propulsion systems at MSFC. The ETO Design Challenge is a hands-on educational program, targeted to middle school students, in which students are assigned a project engaging in related design challenges in their classrooms under the supervision of their teachers. The project is valuable because it can be used by any student and any teacher, even those without technical backgrounds. Students in 12 states: Alabama, Arkansas, California, Colorado, Illinois, Missouri, Montana, New York, Ohio, Tennessee, Virginia, and Washington, are taking part in the MSFC's Earth-to-Orbit program. NASA uses such programs to support educational excellence while participating in educational outreach programs through centers around the country. The Oregon students' teacher, Joanne Fluvog, commented, 'the biggest change I've seen is in the students' motivation and their belief in their ability to think.' Both Justin and Jeff said being involved in a real engineering project has made them realize that 'science is cool.'

Earth-to-Orbit Education Program 'Makes Science Cool'

NASA Technical Reports Server (NTRS)

2002-01-01

In this photograph, students from all over the country gathered and discussed their Earth-to-Orbit (ETO) Design Challenge project at NASA Marshall Space Flight Center in Huntsville, Alabama. These students who are just 'typical teens,' have been spending their time tackling some of the same challenges NASA engineers face when designing propulsion systems at MSFC. The ETO Design Challenge is a hands-on educational program, targeted to middle school students, in which students are assigned a project engaging in related design challenges in their classrooms under the supervision of their teachers. The project is valuable because it can be used by any student, and any teacher, even those without technical backgrounds. Student in 12 states: Alabama, Arkansas, California, Colorado, Illinois, Missouri, Montana, New York, Ohio, Ternessee, Virginia, and Washington, are taking part in MSFC's Earth-to-Orbit program. NASA uses such programs to support educational excellence while participating in educational outreach programs through centers around the country. One of the students' teachers, Joanne Fluvog, commented, 'the biggest change I've seen is in the students' motivation and their belief in their ability to think.' Justin O'Connor and Jeff Alden, students of Lane Middle School in Portland, Oregon, participated in the ETO program and said being involved in a real engineering project has made them realize that 'science is cool.'

Earth Orbit Raise Design for the Artemis Mission

NASA Technical Reports Server (NTRS)

Wiffen, Gregory J.; Sweetser, Theodore H.

2011-01-01

The Artemis mission is an extension of the Themis mission. The Themis mission1 consisted of five identical spacecraft in varying sized Earth orbits designed to make simultaneous measurements of the Earth's electric and magnetic environment. Themis was designed to observe geomagnetic storms resulting from solar wind's interaction with the Earth's magnetosphere. Themis was meant to answer the age old question of why the Earth's aurora can change rapidly on a global scale. The Themis spacecraft are spin stabilized with 20 meter long electric field booms as well as several shorter magnetometer booms. The goal of the Artemis2 mission extension is to deliver the field and particle measuring capabilities of two of the Themis spacecraft to the vicinity of the Moon. The Artemis mission required transferring two Earth orbiting Themis spacecraft on to two different low energy trans-lunar trajectories ultimately ending in lunar orbit. This paper describes the processes that resulted in successful orbit raise designs for both spacecraft.

Unique Non-Keplerian Orbit Vantage Locations for Sun-Earth Connection and Earth Science Vision Roadmaps

NASA Technical Reports Server (NTRS)

Folta, David; Young, Corissa; Ross, Adam

2001-01-01

The purpose of this investigation is to determine the feasibility of attaining and maintaining unique non-Keplerian orbit vantage locations in the Earth/Moon environment in order to obtain continuous scientific measurements. The principal difficulty associated with obtaining continuous measurements is the temporal nature of astrodynamics, i.e., classical orbits. This investigation demonstrates advanced trajectory designs to meet demanding science requirements which cannot be met following traditional orbital mechanic logic. Examples of continuous observer missions addressed include Earth pole-sitters and unique vertical libration orbits that address Sun-Earth Connection and Earth Science Vision roadmaps.

NASA's Earth Science Flight Program overview

NASA Astrophysics Data System (ADS)

Neeck, Steven P.; Volz, Stephen M.

2011-11-01

NASA's Earth Science Division (ESD) conducts pioneering work in Earth system science, the interdisciplinary view of Earth that explores the interaction among the atmosphere, oceans, ice sheets, land surface interior, and life itself that has enabled scientists to measure global and climate changes and to inform decisions by governments, organizations, and people in the United States and around the world. The ESD makes the data collected and results generated by its missions accessible to other agencies and organizations to improve the products and services they provide, including air quality indices, disaster management, agricultural yield projections, and aviation safety. In addition to four missions now in development and 14 currently operating on-orbit, the ESD is now developing the first tier of missions recommended by the 2007 Earth Science Decadal Survey and is conducting engineering studies and technology development for the second tier. Furthermore, NASA's ESD is planning implementation of a set of climate continuity missions to assure availability of key data sets needed for climate science and applications. These include a replacement for the Orbiting Carbon Observatory (OCO), OCO-2, planned for launch in 2013; refurbishment of the SAGE III atmospheric chemistry instrument to be hosted by the International Space Station (ISS) as early as 2014; and the Gravity Recovery and Climate Experiment Follow-On (GRACE FO) mission scheduled for launch in 2016. The new Earth Venture (EV) class of missions is a series of uncoupled, low to moderate cost, small to medium-sized, competitively selected, full orbital missions, instruments for orbital missions of opportunity, and sub-orbital projects.

Design of an unmanned, reusable vehicle to de-orbit debris in Earth orbit

NASA Technical Reports Server (NTRS)

Aziz, Shahed; Cunningham, Timothy W.; Moore-Mccassey, Michelle

1990-01-01

The space debris problem is becoming more important because as orbital missions increase, the amount of debris increases. It was the design team's objective to present alternative designs and a problem solution for a deorbiting vehicle that will alleviate the problem by reducing the amount of large debris in earth orbit. The design team was asked to design a reusable, unmanned vehicle to de-orbit debris in earth orbit. The design team will also construct a model to demonstrate the system configuration and key operating features. The alternative designs for the unmanned, reusable vehicle were developed in three stages: selection of project requirements and success criteria, formulation of a specification list, and the creation of alternatives that would satisfy the standards set forth by the design team and their sponsor. The design team selected a Chain and Bar Shot method for deorbiting debris in earth orbit. The De-orbiting Vehicle (DOV) uses the NASA Orbital Maneuvering Vehicle (OMV) as the propulsion and command modules with the deorbiting module attached to the front.

STS-120 Orbit 2 Flight Control Team Photo

NASA Image and Video Library

2007-10-31

JSC2007-E-095908 (31 Oct. 2007) --- The members of the STS-120 Orbit 2 flight control team pose for a group portrait in the space shuttle flight control room of Houston's Mission Control Center (MCC). Flight director Mike Moses holds the STS-120 mission logo.

Extraction of stability and control derivatives from orbiter flight data

NASA Technical Reports Server (NTRS)

Iliff, Kenneth W.; Shafer, Mary F.

1993-01-01

The Space Shuttle Orbiter has provided unique and important information on aircraft flight dynamics. This information has provided the opportunity to assess the flight-derived stability and control derivatives for maneuvering flight in the hypersonic regime. In the case of the Space Shuttle Orbiter, these derivatives are required to determine if certain configuration placards (limitations on the flight envelope) can be modified. These placards were determined on the basis of preflight predictions and the associated uncertainties. As flight-determined derivatives are obtained, the placards are reassessed, and some of them are removed or modified. Extraction of the stability and control derivatives was justified by operational considerations and not by research considerations. Using flight results to update the predicted database of the orbiter is one of the most completely documented processes for a flight vehicle. This process followed from the requirement for analysis of flight data for control system updates and for expansion of the operational flight envelope. These results show significant changes in many important stability and control derivatives from the preflight database. This paper presents some of the stability and control derivative results obtained from Space Shuttle flights. Some of the limitations of this information are also examined.

STS-119 Flight Control Team in WFCR - Orbit 3 - Flight Director Bryan Lunney

NASA Image and Video Library

2009-03-24

JSC2009-E-061542 (24 March 2009) --- The members of the STS-119 Orbit 3 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA?s Johnson Space Center. Flight director Bryan Lunney (center) near the front.

VIew of Mission Control on first day of ASTP docking in Earth orbit

NASA Technical Reports Server (NTRS)

1975-01-01

An overall view of the Mission Operations Control Room in the Mission Control Center on the first day of the Apollo Soyuz Test Project (ASTP) docking in Earth orbit mission. The American ASTP flight controllers at JSC were monitoring the progress of the Soviet ASTP launch when this photograph was taken. The television monitor shows Cosmonaut Yuri V. Romanenko at his spacecraft communicator's console in the ASTP mission control center in the Soviet Union.

Active Debris Removal mission design in Low Earth Orbit

NASA Astrophysics Data System (ADS)

Martin, Th.; Pérot, E.; Desjean, M.-Ch.; Bitetti, L.

2013-03-01

Active Debris Removal (ADR) aims at removing large sized intact objects ― defunct satellites, rocket upper-stages ― from space crowded regions. Why? Because they constitute the main source of the long-term debris environment deterioration caused by possible future collisions with fragments and worse still with other intact but uncontrolled objects. In order to limit the growth of the orbital debris population in the future (referred to as the Kessler syndrome), it is now highly recommended to carry out such ADR missions, together with the mitigation measures already adopted by national agencies (such as postmission disposal). At the French Space Agency, CNES, and in the frame of advanced studies, the design of such an ADR mission in Low Earth Orbit (LEO) is under evaluation. A two-step preliminary approach has been envisaged. First, a reconnaissance mission based on a small demonstrator (˜500 kg) rendezvousing with several targets (observation and in-flight qualification testing). Secondly, an ADR mission based on a larger vehicle (inherited from the Orbital Transfer Vehicle (OTV) concept) being able to capture and deorbit several preselected targets by attaching a propulsive kit to these targets. This paper presents a flight dynamics level tradeoff analysis between different vehicle and mission concepts as well as target disposal options. The delta-velocity, times, and masses required to transfer, rendezvous with targets and deorbit are assessed for some propelled systems and propellant less options. Total mass budgets are then derived for two end-to-end study cases corresponding to the reconnaissance and ADR missions mentioned above.

Neurovestibular Considerations for Sub-Orbital Space Flight: A Framework for Future Investigation

PubMed Central

Karmali, Faisal; Shelhamer, Mark

2013-01-01

Commercial sub-orbital operators will soon offer the excitement of traveling to space to thousands of people. Based on previous experience in space flight and parabolic flight, sensorimotor disruptions in eye movements, postural stability, and motor coordination are likely in these travelers. Here we propose a framework for developing strategies to overcome these sensorimotor disruptions. We delineate how approaches should differ from those applied to orbital flight and between sub-orbital passengers and pilots based on differing frequency of flights and mission objectives. Sensorimotor adaptation is one strategy for overcoming disruptions; an important question is whether it occurs quickly enough to be of use during periods of reduced and enhanced gravity lasting less than five minutes. Data are presented showing that sensorimotor adaptation of the pitch vestibulo-ocular reflex during parabolic flight takes a few consecutive days of flying to overcome an initial disruption. We conclude with recommendations for operators and researchers to improve safety and comfort during sub-orbital operations. We recommend using parabolic flight as a tool for pre-adapting sub-orbital passengers, along with further research into the required quantity and timing of these pre-adaptation flights and the tasks conducted during these flights. Likewise, for sub-orbital pilots, we recommend emphasizing recency of experience. PMID:20555165

Hardware in-the-Loop Demonstration of Real-Time Orbit Determination in High Earth Orbits

NASA Technical Reports Server (NTRS)

Moreau, Michael; Naasz, Bo; Leitner, Jesse; Carpenter, J. Russell; Gaylor, Dave

2005-01-01

This paper presents results from a study conducted at Goddard Space Flight Center (GSFC) to assess the real-time orbit determination accuracy of GPS-based navigation in a number of different high Earth orbital regimes. Measurements collected from a GPS receiver (connected to a GPS radio frequency (RF) signal simulator) were processed in a navigation filter in real-time, and resulting errors in the estimated states were assessed. For the most challenging orbit simulated, a 12 hour Molniya orbit with an apogee of approximately 39,000 km, mean total position and velocity errors were approximately 7 meters and 3 mm/s respectively. The study also makes direct comparisons between the results from the above hardware in-the-loop tests and results obtained by processing GPS measurements generated from software simulations. Care was taken to use the same models and assumptions in the generation of both the real-time and software simulated measurements, in order that the real-time data could be used to help validate the assumptions and models used in the software simulations. The study makes use of the unique capabilities of the Formation Flying Test Bed at GSFC, which provides a capability to interface with different GPS receivers and to produce real-time, filtered orbit solutions even when less than four satellites are visible. The result is a powerful tool for assessing onboard navigation performance in a wide range of orbital regimes, and a test-bed for developing software and procedures for use in real spacecraft applications.

STS-125 Flight Control Team in WFCR - Orbit 1 - Flight Director Tony Ceccacci

NASA Image and Video Library

2009-05-20

JSC2009-E-120813 (20 May 2009) --- The members of the STS-125 Orbit 1 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Tony Ceccacci holds the STS-125 mission logo.

STS-131 Flight Control Team in WFCR - Orbit 2 - Flight Director Mike Sarafin

NASA Image and Video Library

2010-04-14

JSC2010-E-051978 (14 April 2010) --- The members of the STS-131 Orbit 2 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Mike Sarafin holds the STS-131 mission logo.

STS-131 Flight Control Team in WFCR - Orbit 1 - Flight Director: Richard Jones

NASA Image and Video Library

2010-04-12

JSC2010-E-050680 (12 April 2010) --- The members of the STS-131 Orbit 1 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Richard Jones (second left) is on the front row.

Surveillance of medium and high Earth orbits using large baseline stereovision

NASA Astrophysics Data System (ADS)

Danescu, Radu; Ciurte, Anca; Oniga, Florin; Cristea, Octavian; Dolea, Paul; Dascal, Vlad; Turcu, Vlad; Mircea, Liviu; Moldovan, Dan

2014-11-01

The Earth is surrounded by a swarm of satellites and associated debris known as Resident Space Objects (RSOs). All RSOs will orbit the Earth until they reentry into Earth's atmosphere. There are three main RSO categories: Low Earth Orbit (LEO), when the satellite orbits at an altitude below 1 500 km; a Medium Earth Orbit (MEO) for Global Navigation Satellite Systems (GNSS) at an altitude of around 20 000 km, and a Geostationary Earth Orbit (GEO) (also sometimes called the Clarke orbit), for geostationary satellites, at an altitude of 36 000 km. The Geostationary Earth Orbits and the orbits of higher altitude are also known as High Earth Orbits (HEO). Crucial for keeping an eye on RSOs, the Surveillance of Space (SofS) comprises detection, tracking, propagation of orbital parameters, cataloguing and analysis of these objects. This paper presents a large baseline stereovision based approach for detection and ranging of RSO orbiting at medium to high altitudes. Two identical observation systems, consisting of camera, telescope, control computer and GPS receiver are located 37 km apart, and set to observe the same region of the sky. The telescopes are placed on equatorial mounts able to compensate for the Earth's rotation, so that the stars appear stationary in the acquired images, and the satellites will appear as linear streaks. The two cameras are triggered simultaneously. The satellite streaks are detected in each image of the stereo pair using its streak-like appearance against point-like stars, the motion of the streaks between successive frames, and the stereo disparity. The detected satellite pixels are then put into correspondence using the epipolar geometry, and the 3D position of the satellite in the Earth Center, Earth Fixed (ECEF) reference frame is computed using stereo triangulation. Preliminary tests have been performed, for both MEO and HEO orbits. The preliminary results indicate a very high detection rate for MEO orbits, and good detection rate for

STS-40 orbital acceleration research experiment flight results during a typical sleep period

NASA Technical Reports Server (NTRS)

Blanchard, Robert C.; Nicholson, John Y.; Ritter, James R.

1992-01-01

The Orbital Acceleration Research Experiment (OARE), an electrostatic accelerometer package with complete on-orbit calibration capabilities was flown aboard Shuttle on STS-40. The instrument is designed to measure and record the Shuttle aerodynamic acceleration environment from the free molecule flow regime through the rarefied flow transition into the hypersonic continuum regime. Because of its sensitivity, the OARE instrument detects aerodynamic behavior of the Shuttle while in low-earth orbit. A 2-h orbital time period on day seven of the mission, when the crew was asleep and other spacecraft activities were at a minimum, was examined. Examination of the model with the flight data shows the instrument to be sensitive to all major expected low-frequency acceleration phenomena; however, some erratic instrument bias behavior persists in two axes. In these axes, the OARE data can be made to match a comprehensive atmospheric-aerodynamic model by making bias adjustments and slight liner corrections for drift.

STS-125 Flight Control Team in WFCR - Orbit 3 - Flight Director Paul Dye

NASA Image and Video Library

2009-05-20

JSC2009-E-120846 (20 May 2009) --- The members of the STS-125 Orbit 3 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Paul Dye (center left) is visible on the front row.

Space Shuttle Orbiter Approach and Landing Test Evaluation Report. Captive-Active Flight Test Summary

NASA Technical Reports Server (NTRS)

1977-01-01

Captive-active tests consisted of three mated carrier aircraft/Orbiter flights with an active manned Orbiter. The objectives of this series of flights were to (1) verify the separation profile, (2) verify the integrated structure, aerodynamics, and flight control system, (3) verify Orbiter integrated system operations, and (4) refine and finalize carrier aircraft, Orbiter crew, and ground procedures in preparation for free flight tests. A summary description of the flights is presented with assessments of flight test requirements, and of the performance operations, and of significant flight anomalies is included.

3D Orbit Visualization for Earth-Observing Missions

NASA Technical Reports Server (NTRS)

Jacob, Joseph C.; Plesea, Lucian; Chafin, Brian G.; Weiss, Barry H.

2011-01-01

This software visualizes orbit paths for the Orbiting Carbon Observatory (OCO), but was designed to be general and applicable to any Earth-observing mission. The software uses the Google Earth user interface to provide a visual mechanism to explore spacecraft orbit paths, ground footprint locations, and local cloud cover conditions. In addition, a drill-down capability allows for users to point and click on a particular observation frame to pop up ancillary information such as data product filenames and directory paths, latitude, longitude, time stamp, column-average dry air mole fraction of carbon dioxide, and solar zenith angle. This software can be integrated with the ground data system for any Earth-observing mission to automatically generate daily orbit path data products in Google Earth KML format. These KML data products can be directly loaded into the Google Earth application for interactive 3D visualization of the orbit paths for each mission day. Each time the application runs, the daily orbit paths are encapsulated in a KML file for each mission day since the last time the application ran. Alternatively, the daily KML for a specified mission day may be generated. The application automatically extracts the spacecraft position and ground footprint geometry as a function of time from a daily Level 1B data product created and archived by the mission s ground data system software. In addition, ancillary data, such as the column-averaged dry air mole fraction of carbon dioxide and solar zenith angle, are automatically extracted from a Level 2 mission data product. Zoom, pan, and rotate capability are provided through the standard Google Earth interface. Cloud cover is indicated with an image layer from the MODIS (Moderate Resolution Imaging Spectroradiometer) aboard the Aqua satellite, which is automatically retrieved from JPL s OnEarth Web service.

A Cryogenic Propellant Production Depot for Low Earth Orbit

NASA Technical Reports Server (NTRS)

Potter, Seth D.; Henley, Mark; Guitierrez, Sonia; Fikes, John; Carrington, Connie; Smitherman, David; Gerry, Mark; Sutherlin, Steve; Beason, Phil; Howell, Joe (Technical Monitor)

2001-01-01

The cost of access to space beyond low Earth orbit can be lowered if vehicles can refuel in orbit. The power requirements for a propellant depot that electrolyzes water and stores cryogenic oxygen and hydrogen can be met using technology developed for space solar power. A propellant depot is described that will be deployed in a 400 km circular equatorial orbit, receive tanks of water launched into a lower orbit from Earth by gun launch or reusable launch vehicle, convert the water to liquid hydrogen and oxygen, and store Lip to 500 metric tonnes of cryogenic propellants. The propellant stored in the depot can support transportation from low Earth orbit to geostationary Earth orbit, the Moon, LaGrange points, Mars, etc. The tanks are configured in an inline gravity-gradient configuration to minimize drag and settle the propellant. Temperatures can be maintained by body-mounted radiators; these will also provide some shielding against orbital debris. Power is supplied by a pair of solar arrays mounted perpendicular to the orbital plane, which rotate once per orbit to track the Sun. In the longer term, cryogenic propellant production technology can be applied to a larger LEO depot, as well as to the use of lunar water resources at a similar depot elsewhere.

STS-40 orbital acceleration research experiment flight results during a typical sleep period

NASA Technical Reports Server (NTRS)

Blanchard, R. C.; Nicholson, J. Y.; Ritter, J. R.

1992-01-01

The Orbital Acceleration Research Experiment (OARE), an electrostatic accelerometer package with complete on-orbit calibration capabilities, was flown for the first time aboard the Space Shuttle on STS-40. This is also the first time an accelerometer package with nano-g sensitivity and a calibration facility has flown aboard the Space Shuttle. The instrument is designed to measure and record the Space Shuttle aerodynamic acceleration environment from the free molecule flow regime through the rarified flow transition into the hypersonic continuum regime. Because of its sensitivity, the OARE instrument defects aerodynamic behavior of the Space Shuttle while in low-earth orbit. A 2-hour orbital time period on day seven of the mission, when the crew was asleep and other spacecraft activities were at a minimum, was examined. During the flight, a 'trimmed-mean' filter was used to produce high quality, low frequency data which was successfully stored aboard the Space Shuttle in the OARE data storage system. Initial review of the data indicated that, although the expected precision was achieved, some equipment problems occurred resulting in uncertain accuracy. An acceleration model which includes aerodynamic, gravity-gradient, and rotational effects was constructed and compared with flight data. Examination of the model with the flight data shows the instrument to be sensitive to all major expected low frequency acceleration phenomena; however, some erratic instrument bias behavior persists in two axes. In these axes, the OARE data can be made to match a comprehensive atmospheric-aerodynamic model by making bias adjustments and slight linear corrections for drift. The other axis does not exhibit these difficulties and gives good agreement with the acceleration model.

Pre-Flight Tests with Astronauts, Flight and Ground Hardware, to Assure On-Orbit Success

NASA Technical Reports Server (NTRS)

Haddad Michael E.

2010-01-01

On-Orbit Constraints Test (OOCT's) refers to mating flight hardware together on the ground before they will be mated on-orbit or on the Lunar surface. The concept seems simple but it can be difficult to perform operations like this on the ground when the flight hardware is being designed to be mated on-orbit in a zero-g/vacuum environment of space or low-g/vacuum environment on the Lunar/Mars Surface. Also some of the items are manufactured years apart so how are mating tasks performed on these components if one piece is on-orbit/on Lunar/Mars surface before its mating piece is planned to be built. Both the Internal Vehicular Activity (IVA) and Extra-Vehicular Activity (EVA) OOCT's performed at Kennedy Space Center will be presented in this paper. Details include how OOCT's should mimic on-orbit/Lunar/Mars surface operational scenarios, a series of photographs will be shown that were taken during OOCT's performed on International Space Station (ISS) flight elements, lessons learned as a result of the OOCT's will be presented and the paper will conclude with possible applications to Moon and Mars Surface operations planned for the Constellation Program.

Computer modeling of high-voltage solar array experiment using the NASCAP/LEO (NASA Charging Analyzer Program/Low Earth Orbit) computer code

NASA Astrophysics Data System (ADS)

Reichl, Karl O., Jr.

1987-06-01

The relationship between the Interactions Measurement Payload for Shuttle (IMPS) flight experiment and the low Earth orbit plasma environment is discussed. Two interactions (parasitic current loss and electrostatic discharge on the array) may be detrimental to mission effectiveness. They result from the spacecraft's electrical potentials floating relative to plasma ground to achieve a charge flow equilibrium into the spacecraft. The floating potentials were driven by external biases applied to a solar array module of the Photovoltaic Array Space Power (PASP) experiment aboard the IMPS test pallet. The modeling was performed using the NASA Charging Analyzer Program/Low Earth Orbit (NASCAP/LEO) computer code which calculates the potentials and current collection of high-voltage objects in low Earth orbit. Models are developed by specifying the spacecraft, environment, and orbital parameters. Eight IMPS models were developed by varying the array's bias voltage and altering its orientation relative to its motion. The code modeled a typical low Earth equatorial orbit. NASCAP/LEO calculated a wide variety of possible floating potential and current collection scenarios. These varied directly with both the array bias voltage and with the vehicle's orbital orientation.

Low Earth Orbit Environmental Durability of Recently Developed Thermal Control Coatings

NASA Technical Reports Server (NTRS)

Jaworske, Donald A.

2015-01-01

The Materials International Space Station Experiment provided a means to expose materials and devices to the low Earth orbit environment on the exterior of the International Space Station. By returning the specimens to Earth after flight, the specimens could be evaluated by comparison with pre-flight measurements. One area of continuing interest is thermal control paints and coatings that are applied to exterior surfaces of spacecraft. Though traditional radiator coatings have been available for decades, recent work has focused on new coatings that offer custom deposition or custom optical properties. The custom deposition of interest is plasma spraying and one type of coating recently developed as part of a Small Business Innovative Research effort was designed to be plasma sprayed onto radiator surfaces. The custom optical properties of interest are opposite to those of a typical radiator coating, having a combination of high solar absorptance and low infrared emittance for solar absorber applications, and achieved in practice via a cermet coating. Selected specimens of the plasma sprayed coatings and the solar absorber coating were flown on Materials International Space Station Experiment 7, and were recently returned to Earth for post-flight analyses. For the plasma sprayed coatings in the ram direction, one specimen increased in solar absorptance and one specimen decreased in solar absorptance, while the plasma sprayed coatings in the wake direction changed very little in solar absorptance. For the cermet coating deployed in both the ram and wake directions, the solar absorptance increased. Interestingly, all coatings showed little change in infrared emittance.

The effect of the low Earth orbit environment on space solar cells: Results of the Advanced Photovoltaic Experiment (S0014)

NASA Technical Reports Server (NTRS)

Brinker, David J.; Hickey, John R.; Scheiman, David A.

1993-01-01

The results of post-flight performance testing of the solar cells flown on the Advanced Photovoltaic Experiment are reported. Comparison of post-flight current-voltage characteristics with similar pre-flight data revealed little or no change in solar cell conversion efficiency, confirming the reliability and endurance of space photovoltaic cells. This finding is in agreement with the lack of significant physical changes in the solar cells despite nearly six years in the low Earth orbit environment.

A Framework for Orbital Performance Evaluation in Distributed Space Missions for Earth Observation

NASA Technical Reports Server (NTRS)

Nag, Sreeja; LeMoigne-Stewart, Jacqueline; Miller, David W.; de Weck, Olivier

2015-01-01

Distributed Space Missions (DSMs) are gaining momentum in their application to earth science missions owing to their unique ability to increase observation sampling in spatial, spectral and temporal dimensions simultaneously. DSM architectures have a large number of design variables and since they are expected to increase mission flexibility, scalability, evolvability and robustness, their design is a complex problem with many variables and objectives affecting performance. There are very few open-access tools available to explore the tradespace of variables which allow performance assessment and are easy to plug into science goals, and therefore select the most optimal design. This paper presents a software tool developed on the MATLAB engine interfacing with STK, for DSM orbit design and selection. It is capable of generating thousands of homogeneous constellation or formation flight architectures based on pre-defined design variable ranges and sizing those architectures in terms of predefined performance metrics. The metrics can be input into observing system simulation experiments, as available from the science teams, allowing dynamic coupling of science and engineering designs. Design variables include but are not restricted to constellation type, formation flight type, FOV of instrument, altitude and inclination of chief orbits, differential orbital elements, leader satellites, latitudes or regions of interest, planes and satellite numbers. Intermediate performance metrics include angular coverage, number of accesses, revisit coverage, access deterioration over time at every point of the Earth's grid. The orbit design process can be streamlined and variables more bounded along the way, owing to the availability of low fidelity and low complexity models such as corrected HCW equations up to high precision STK models with J2 and drag. The tool can thus help any scientist or program manager select pre-Phase A, Pareto optimal DSM designs for a variety of science

Earth from Orbit 2014

NASA Image and Video Library

2015-04-20

Every day of every year, NASA satellites provide useful data about our home planet, and along the way, some beautiful images as well. This video includes satellite images of Earth in 2014 from NASA and its partners as well as photos and a time lapse video from the International Space Station. We’ve also included a range of data visualizations, model runs, and a conceptual animation that were produced in 2014 (but in some cases might have been utilizing data from earlier years.) Credit: NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Stability and control flight test results of the space transportation system's orbiter

NASA Technical Reports Server (NTRS)

Culp, M. A.; Cooke, D. R.

1982-01-01

Flight testing of the Space Shuttle Orbiter is in progress and current results of the post-flight aerodynamic analyses are discussed. The purpose of these analyses is to reduce the pre-flight aerodynamic uncertainties, thereby leading to operational certification of the Orbiter flight envelope relative to the integrated airframe and flight control system. Primary data reduction is accomplished with a well documented maximum likelihood system identification techniques.

The IMISS-1 Experiment for Recording and Analysis of Accelerations in Orbital Flight

NASA Astrophysics Data System (ADS)

Sadovnichii, V. A.; Alexandrov, V. V.; Bugrov, D. I.; Lemak, S. S.; Pakhomov, V. B.; Panasyuk, M. I.; Petrov, V. L.; Yashin, I. V.

2018-03-01

The IMISS-1 experiment represents the second step in solving the problem of the creation of the gaze stabilization corrector. This device is designed to correct the effect of the gaze stabilization delay under microgravity. IMISS-1 continues research started by the Tat'yana-2 satellite. This research will be continued on board the International Space Station. At this stage we study the possibility of registration of angular and linear accelerations acting on the sensitive mass in terms of Low Earth Orbit flight, using MEMS sensors.

Review of Low Earth Orbital (LEO) flight experiments

NASA Technical Reports Server (NTRS)

Leger, L.; Santosmason, B.; Visentine, J.; Kuminecz, J.

1987-01-01

The atomic oxygen flux exposure experiments flown on Space Shuttle flights STS-5 and STS-8 are described along with the results of measurements made on hardware returned from the Solar Maximum repair mission (Space Shuttle flight 41-C). In general, these experiments have essentially provided for passive exposure of samples to oxygen fluences of approximately 1 to 3.5 x 10(20) atoms/sq cm. Atmospheric density is used to derive fluence and is dependent on solar activity, which has been on the decline side of the 11-year cycle. Thus, relatively low flight altitudes of less than 300 km were used to acquire these exposures. After exposure, the samples were analyzed using various methods ranging from mass loss to extensive scanning electron microscopy and surface analysis techniques. Results are summarized and implications for the space station are discussed.

A Small Spacecraft Swarm Deployment and Stationkeeping Strategy for Sun-Earth L1 Halo Orbits

NASA Technical Reports Server (NTRS)

Conn, Tracie R.; Bookbinder, Jay

2018-01-01

Spacecraft orbits about the Sun-Earth librarian point L1 have been of interest since the 1950s. An L1 halo orbit was first achieved with the International Sun-Earth Explorer-3 (ISEE-3) mission, and similar orbits around Sun-Earth L1 were achieved in the Solar and Heliospheric Observatory (SOHO), Advanced Composition Explorer (ACE), Genesis, and Deep Space Climate Observatory (DSCOVR) missions. With recent advancements in CubeSat technology, we envision that it will soon be feasible to deploy CubeSats at L1. As opposed to these prior missions where one large satellite orbited alone, a swarm of CubeSats at L1 would enable novel science data return, providing a topology for intersatellite measurements of heliophysics phenomena both spatially and temporally, at varying spatial scales.The purpose of this iPoster is to present a flight dynamics strategy for a swarm of numerous CubeSats orbiting Sun-Earth L1. The presented method is a coupled, two-part solution. First, we present a deployment strategy for the CubeSats that is optimized to produce prescribed, time-varying intersatellite baselines for the purposes of collecting magnetometer data as well as radiometric measurements from cross-links. Second, we employ a loose control strategy that was successfully applied to SOHO and ACE for minimized stationkeeping fuel expenditure. We emphasize that the presented solution is practical within the current state-of-the-art and heritage CubeSat technology, citing capabilities of CubeSat designs that will launch on the upcoming Exploration Mission 1 (EM-1) to lunar orbits and beyond. Within this iPoster, we present animations of the simulated deployment strategy and resulting spacecraft trajectories. Mission design parameters such as total delta-v required for long-term station keeping and minimummaximummean spacecraft separation distances are also presented.

A Small Spacecraft Swarm Deployment and Stationkeeping Strategy for Sun-Earth L1 Halo Orbits

NASA Astrophysics Data System (ADS)

Renea Conn, Tracie; Bookbinder, Jay

2018-01-01

Spacecraft orbits about the Sun-Earth librarian point L1 have been of interest since the 1950s. An L1 halo orbit was first achieved with the International Sun-Earth Explorer-3 (ISEE-3) mission, and similar orbits around Sun-Earth L1 were achieved in the Solar and Heliospheric Observatory (SOHO), Advanced Composition Explorer (ACE), Genesis, and Deep Space Climate Observatory (DSCOVR) missions. With recent advancements in CubeSat technology, we envision that it will soon be feasible to deploy CubeSats at L1. As opposed to these prior missions where one large satellite orbited alone, a swarm of CubeSats at L1 would enable novel science data return, providing a topology for intersatellite measurements of heliophysics phenomena both spatially and temporally, at varying spatial scales.The purpose of this iPoster is to present a flight dynamics strategy for a swarm of numerous CubeSats orbiting Sun-Earth L1. The presented method is a coupled, two-part solution. First, we present a deployment strategy for the CubeSats that is optimized to produce prescribed, time-varying intersatellite baselines for the purposes of collecting magnetometer data as well as radiometric measurements from cross-links. Second, we employ a loose control strategy that was successfully applied to SOHO and ACE for minimized stationkeeping propellant expenditure. We emphasize that the presented solution is practical within the current state-of-the-art and heritage CubeSat technology, citing capabilities of CubeSat designs that will launch on the upcoming Exploration Mission 1 (EM-1) to lunar orbits and beyond. Within this iPoster, we present animations of the simulated deployment strategy and resulting spacecraft trajectories. Mission design parameters such as total Δv required for long-term station keeping and minimum/maximum/mean spacecraft separation distances are also presented.

Perturbed Equations of Motion for Formation Flight Near the Sun-Earth L2 Point

NASA Technical Reports Server (NTRS)

Luquette, Richard; Segerman, A. M.; Zedd, M. F.

2005-01-01

NASA is planning missions to the vicinity of the Sun-Earth L(sub 2) point, some involving a distributed system of telescope spacecraft, configured in a plane about a hub. Several sets of differential equations are written for the formation flight of such telescopes relative to the hub, with varying levels of fidelity. Effects are cast as additive perturbations to the circular restricted three-body problem, expanded in terms of the system distanced, to an accuracy of 10-20 m. These include Earth's orbital eccentricity, lunar motion, solar radiation pressure, and small thrusting forces. Simulations validating the expanded differential equations are presented.

Supportability for Beyond Low Earth Orbit Missions

NASA Technical Reports Server (NTRS)

Crillo, William M.; Goodliff, Kandyce E.; Aaseng, Gordon; Stromgren, Chel; Maxwell, Andrew J.

2011-01-01

Exploration beyond Low Earth Orbit (LEO) presents many unique challenges that will require changes from current Supportability approaches. Currently, the International Space Station (ISS) is supported and maintained through a series of preplanned resupply flights, on which spare parts, including some large, heavy Orbital Replacement Units (ORUs), are delivered to the ISS. The Space Shuttle system provided for a robust capability to return failed components to Earth for detailed examination and potential repair. Additionally, as components fail and spares are not already on-orbit, there is flexibility in the transportation system to deliver those required replacement parts to ISS on a near term basis. A similar concept of operation will not be feasible for beyond LEO exploration. The mass and volume constraints of the transportation system and long envisioned mission durations could make it difficult to manifest necessary spares. The supply of on-demand spare parts for missions beyond LEO will be very limited or even non-existent. In addition, the remote nature of the mission, the design of the spacecraft, and the limitations on crew capabilities will all make it more difficult to maintain the spacecraft. Alternate concepts of operation must be explored in which required spare parts, materials, and tools are made available to make repairs; the locations of the failures are accessible; and the information needed to conduct repairs is available to the crew. In this paper, ISS heritage information is presented along with a summary of the challenges of beyond LEO missions. A number of Supportability issues are discussed in relation to human exploration beyond LEO. In addition, the impacts of various Supportability strategies will be discussed. Any measure that can be incorporated to reduce risk and improve mission success should be evaluated to understand the advantages and disadvantages of implementing those measures. Finally, an effort to model and evaluate

STS-56 crewmembers on aft flight deck of Discovery, Orbiter Vehicle (OV) 103

NASA Technical Reports Server (NTRS)

1993-01-01

STS-56 crewmembers pose on aft flight deck of Discovery, Orbiter Vehicle (OV) 103, for this in-cabin electronic still camera (ESC) photograph. Clockwise from the bottom right corner are Commander Kenneth Cameron, Mission Specialist 3 (MS3) Ellen Ochoa, MS2 Kenneth D. Cockrell, and Pilot Stephen S. Oswald. The crewmembers are positioned in front of the onorbit station. The image was recorder with the Hand-held, Earth-oriented, Real-time, Cooperative, User-friendly, Location-targeting and Environmental System (HERCULES). HERCULES is a device that makes it simple for Shuttle crewmembers to take pictures of Earth as they merely point and shoot any interesting feature, whose latitude and longitude are automatically determined in real time. In-cabin shots are for test purposes only.

Aerobraking orbital transfer vehicle

NASA Technical Reports Server (NTRS)

Scott, Carl D. (Inventor); Nagy, Kornel (Inventor); Roberts, Barney B. (Inventor); Ried, Robert C. (Inventor); Kroll, Kenneth R. (Inventor); Gamble, Joe (Inventor)

1989-01-01

An aerobraking orbital transfer vehicle which includes an aerobraking device which also serves as a heat shield in the shape of a raked-off elliptic or circular cone with a circular or elliptical base, and with an ellipsoid or other blunt shape nose. The aerobraking device is fitted with a toroid-like skirt and is integral with the support structure of the propulsion system and other systems of the space vehicle. The vehicle is intended to be transported in components to a space station in lower earth orbit where it is assembled for use as a transportation system from low earth orbit to geosynchronous earth orbit and return. Conventional guidance means are included for autonomous flight.

STS-125 Flight Control Team in WFCR - Orbit 2 - Flight Director Richard LaBrode

NASA Image and Video Library

2009-05-20

JSC2009-E-120845 (20 May 2009) --- The members of the STS-125 Orbit 2 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Rick LaBrode (right) is visible on the front row.

Ofeq-2 orbit, attitude, and flight evaluation

NASA Astrophysics Data System (ADS)

Grumer, Michael; Komem, Joseph; Kronenfeld, Joseph; Kubitski, Ophir; Lorber, Vitaly; Shyldkrot, Haim

1992-02-01

The most significant events and phenomena that occurred during the Ofeq-2 flight are evaluated in this work. Particular attention is paid to the physical and technological factors which affected its orbital lifetime. Comparison of Ofeq-2 telemetry results with prelaunch estimations and with Ofeq-1 flight data are presented. The satellite's orbit and mission characteristics are defined and the principal systems of Ofeq-2 are described. Topics addressed include the interaction between the spinner's attitude with respect to the sun and consequent electric power generation. The coning angle development history, the role of the solar data evaluation, and the factors influencing drag are also analyzed. All of these affected the Ofeq-2 power outage-recovery event. The orbit determination and the coning angle evolution estimation methods are discussed in some detail. A brief report on radiation effects on computer RAM (random access memory) is also given. An integrative systems engineering approach summary of the telemetry data reconstruction and analysis concludes the paper.

Orbital flight test shuttle external tank aerothermal flight evaluation, volume 1

NASA Technical Reports Server (NTRS)

Praharaj, Sarat C.; Engel, Carl D.; Warmbrod, John D.

1986-01-01

This 3-volume report discusses the evaluation of aerothermal flight measurements made on the orbital flight test Space Shuttle External Tanks (ETs). Six ETs were instrumented to measure various quantities during flight; including heat transfer, pressure, and structural temperature. The flight data was reduced and analyzed against math models established from an extensive wind tunnel data base and empirical heat-transfer relationships. This analysis has supported the validity of the current aeroheating methodology and existing data base; and, has also identified some problem areas which require methodology modifications. This is Volume 1, an Executive Summary. Volume 2 contains Appendices A (Aerothermal Comparisons) and B (Flight Derived h sub 1/h sub u vs. M sub inf. Plots), and Volume 3 contains Appendix C (Comparison of Interference Factors among OFT Flight, Prediction and 1H-97A Data), Appendix D (Freestream Stanton Number and Reynolds Number Correlation for Flight and Tunnel Data), and Appendix E (Flight-Derived h sub i/h sub u Tables).

Orbital flight test shuttle external tank aerothermal flight evaluation, volume 3

NASA Technical Reports Server (NTRS)

Praharaj, Sarat C.; Engel, Carl D.; Warmbrod, John D.

1986-01-01

This 3-volume report discusses the evaluation of aerothermal flight measurements made on the orbital flight test Space Shuttle External Tanks (ETs). Six ETs were instrumented to measure various quantities during flight; including heat transfer, pressure, and structural temperature. The flight data was reduced and analyzed against math models established from an extensive wind tunnel data base and empirical heat-transfer relationships. This analysis has supported the validity of the current aeroheating methodology and existing data base; and, has also identified some problem areas which require methodology modifications. Volume 1 is the Executive Summary. Volume 2 contains Appendix A (Aerothermal Comparisons), and Appendix B (Flight-Derived h sub 1/h sub u vs. M sub inf. Plots). This is Volume 3, containing Appendix C (Comparison of Interference Factors between OFT Flight, Prediction and 1H-97A Data), Appendix D (Freestream Stanton Number and Reynolds Number Correlation for Flight and Tunnel Data), and Appendix E (Flight-Derived h sub i/h sub u Tables).

Orbital flight test shuttle external tank aerothermal flight evaluation, volume 2

NASA Technical Reports Server (NTRS)

Praharaj, Sarat C.; Engel, Carl D.; Warmbrod, John D.

1986-01-01

This 3-volume report discusses the evaluation of aerothermal flight measurements made on the orbital flight test Space Shuttle External Tanks (ETs). Six ETs were instrumented to measure various quantities during flight; including heat transfer, pressure, and structural temperature. The flight data was reduced and analyzed against math models established from an extensive wind tunnel data base and empirical heat-transfer relationships. This analysis has supported the validity of the current aeroheating methodology and existing data base; and, has also identified some problem areas which require methodology modifications. Volume 1 is the Executive Summary. This is volume 2, containing Appendix A (Aerothermal Comparisons), and Appendix B (Flight-Derived h sub i/h sub u vs. M sub inf. Plots). Volume 3 contains Appendix C (Comparison of Interference Factors between OFT Flight, Prediction and 1H-97A Data), Appendix D (Freestream Stanton Number and Reynolds Number Correlation for Flight and Tunnel Data), and Appendix E (Flight-Derived h sub i/h sub u Tables).

In-Orbit Collision Analysis for VEGA Second Flight

NASA Astrophysics Data System (ADS)

Volpi, M.; Fossati, T.; Battie, F.

2013-08-01

ELV, as prime contractor of the VEGA launcher, which operates in the protected LEO zone (up to 2000 km altitude), has to demonstrate that it abides by ESA debris mitigation rules, as well as by those imposed by the French Law on Space Operations (LOS). After the full success of VEGA qualification flight, the second flight(VV02) will extend the qualification domain of the launcher to multi-payload missions, with the release of two satellites (Proba-V and VNRedSat-1) and one Cubesat (ESTCube-1) on different SSO orbits The multi-payload adapter, VESPA, also separates its upper part before the second payload release. This paper will present the results of the long-term analyses on inorbit collision between these different bodies. Typical duration of propagation requested by ELV customer is around 50 orbits, requiring a state-of-the-art simulator able to compute efficiently orbits disturbs, usually neglected in launcher trajectory optimization itself. To address the issue of in-orbit collision, ELV has therefore developed its own simulator, POLPO [1], a FORTRAN code which performs the long-term propagation of the released objects trajectories and computes the mutual distance between them. The first part of the paper shall introduce the simulator itself, explaining the computation method chosen and briefly discussing the perturbing effects and their models taken into account in the tool, namely: - gravity field modeling (zonal and tesseral harmonics) - atmospheric model - solar pressure - third-body interaction A second part will describe the application of the in-orbit collision analysis to the second flight mission. Main characteristics of the second flight will be introduced, as well as the dispersions considered for the Monte-Carlo analysis performed. The results of the long-term collision analysis between all the separated bodies will then be presented and discussed.

Using Lunar Observations to Validate In-Flight Calibrations of Clouds and Earth Radiant Energy System Instruments

NASA Technical Reports Server (NTRS)

Daniels, Janet L.; Smith, G. Louis; Priestley, Kory J.; Thomas, Susan

2014-01-01

The validation of in-orbit instrument performance requires stability in both instrument and calibration source. This paper describes a method of validation using lunar observations scanning near full moon by the Clouds and Earth Radiant Energy System (CERES) instruments. Unlike internal calibrations, the Moon offers an external source whose signal variance is predictable and non-degrading. From 2006 to present, in-orbit observations have become standardized and compiled for the Flight Models-1 and -2 aboard the Terra satellite, for Flight Models-3 and -4 aboard the Aqua satellite, and beginning 2012, for Flight Model-5 aboard Suomi-NPP. Instrument performance parameters which can be gleaned are detector gain, pointing accuracy and static detector point response function validation. Lunar observations are used to examine the stability of all three detectors on each of these instruments from 2006 to present. This validation method has yielded results showing trends per CERES data channel of 1.2% per decade or less.

Earth Orbiting Support Systems for commercial low Earth orbit data relay: Assessing architectures through tradespace exploration

NASA Astrophysics Data System (ADS)

Palermo, Gianluca; Golkar, Alessandro; Gaudenzi, Paolo

2015-06-01

As small satellites and Sun Synchronous Earth Observation systems are assuming an increased role in nowadays space activities, including commercial investments, it is of interest to assess how infrastructures could be developed to support the development of such systems and other spacecraft that could benefit from having a data relay service in Low Earth Orbit (LEO), as opposed to traditional Geostationary relays. This paper presents a tradespace exploration study of the architecture of such LEO commercial satellite data relay systems, here defined as Earth Orbiting Support Systems (EOSS). The paper proposes a methodology to formulate architectural decisions for EOSS constellations, and enumerate the corresponding tradespace of feasible architectures. Evaluation metrics are proposed to measure benefits and costs of architectures; lastly, a multicriteria Pareto criterion is used to downselect optimal architectures for subsequent analysis. The methodology is applied to two case studies for a set of 30 and 100 customer-spacecraft respectively, representing potential markets for LEO services in Exploration, Earth Observation, Science, and CubeSats. Pareto analysis shows how increased performance of the constellation is always achieved by an increased node size, as measured by the gain of the communications antenna mounted on EOSS spacecraft. On the other hand, nonlinear trends in optimal orbital altitude, number of satellites per plane, and number of orbital planes, are found in both cases. An upward trend in individual node memory capacity is found, although never exceeding 256 Gbits of onboard memory for both cases that have been considered, assuming the availability of a polar ground station for EOSS data downlink. System architects can use the proposed methodology to identify optimal EOSS constellations for a given service pricing strategy and customer target, thus identifying alternatives for selection by decision makers.

Pervasive orbital eccentricities dictate the habitability of extrasolar earths.

PubMed

Kita, Ryosuke; Rasio, Frederic; Takeda, Genya

2010-09-01

The long-term habitability of Earth-like planets requires low orbital eccentricities. A secular perturbation from a distant stellar companion is a very important mechanism in exciting planetary eccentricities, as many of the extrasolar planetary systems are associated with stellar companions. Although the orbital evolution of an Earth-like planet in a stellar binary system is well understood, the effect of a binary perturbation on a more realistic system containing additional gas-giant planets has been very little studied. Here, we provide analytic criteria confirmed by a large ensemble of numerical integrations that identify the initial orbital parameters leading to eccentric orbits. We show that an extrasolar earth is likely to experience a broad range of orbital evolution dictated by the location of a gas-giant planet, which necessitates more focused studies on the effect of eccentricity on the potential for life.

An Earth-mass planet orbiting α Centauri B.

PubMed

Dumusque, Xavier; Pepe, Francesco; Lovis, Christophe; Ségransan, Damien; Sahlmann, Johannes; Benz, Willy; Bouchy, François; Mayor, Michel; Queloz, Didier; Santos, Nuno; Udry, Stéphane

2012-11-08

Exoplanets down to the size of Earth have been found, but not in the habitable zone--that is, at a distance from the parent star at which water, if present, would be liquid. There are planets in the habitable zone of stars cooler than our Sun, but for reasons such as tidal locking and strong stellar activity, they are unlikely to harbour water-carbon life as we know it. The detection of a habitable Earth-mass planet orbiting a star similar to our Sun is extremely difficult, because such a signal is overwhelmed by stellar perturbations. Here we report the detection of an Earth-mass planet orbiting our neighbour star α Centauri B, a member of the closest stellar system to the Sun. The planet has an orbital period of 3.236 days and is about 0.04 astronomical units from the star (one astronomical unit is the Earth-Sun distance).

STS-132 Flight Control Team in WFCR - Orbit 1

NASA Image and Video Library

2010-05-22

JSC2010-E-086698 (22 May 2010) --- The members of the STS-132 Orbit 1 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Mike Sarafin (center) is visible on the front row.

Integrated Digital Flight Control System for the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

1973-01-01

The objectives of the integrated digital flight control system (DFCS) is to provide rotational and translational control of the space shuttle orbiter in all phases of flight: from launch ascent through orbit to entry and touchdown, and during powered horizontal flights. The program provides a versatile control system structure while maintaining uniform communications with other programs, sensors, and control effectors by using an executive routine/functional subroutine format. The program reads all external variables at a single point, copies them into its dedicated storage, and then calls the required subroutines in the proper sequence. As a result, the flight control program is largely independent of other programs in the computer complex and is equally insensitive to characteristics of the processor configuration. The integrated structure is described of the control system and the DFCS executive routine which embodies that structure. The input and output, including jet selection are included. Specific estimation and control algorithm are shown for the various mission phases: cruise (including horizontal powered flight), entry, on-orbit, and boost. Attitude maneuver routines that interface with the DFCS are included.

Periodic Trojan-type orbits in the earth-sun system

NASA Technical Reports Server (NTRS)

Weissman, P. R.; Wetherill, G. W.

1974-01-01

Periodic orbits about the triangular equilibrium points are found for the planar restricted three-body problem using the earth-sun system. The maximum semimajor axis for tadpole orbits ranges from the infinitesimal orbit at 1.000 AU to the near-limiting orbit at 1.00285 AU. Horseshoe orbits are found for 1.0029 to 1.0080 AU, larger horseshoes being unstable because of close approaches to the earth. Using stability tests devised by Rabe (1961, 1962), the limit of stability for nonperiodic orbits is found to occur for maximum semimajor axes near 1.0020 AU. In addition, near-periodic tadpole orbits appear to be stable against perturbations by Jupiter and Venus for periods of at least 10,000 yr. The possibility that minor planets actually exist in such orbits is considered.

STS-132 Flight Control Team in WFCR - Orbit 2

NASA Image and Video Library

2010-05-20

JSC2010-E-086451 (20 May 2010) --- The members of the STS-132 Orbit 2 flight control team pose for a group portrait in the space shuttle flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Chris Edelen (second left) is visible on the front row.

Analysis of orbital perturbations acting on objects in orbits near geosynchronous earth orbit

NASA Technical Reports Server (NTRS)

Friesen, Larry J.; Jackson, Albert A., IV; Zook, Herbert A.; Kessler, Donald J.

1992-01-01

The paper presents a numerical investigation of orbital evolution for objects started in GEO or in orbits near GEO in order to study potential orbital debris problems in this region. Perturbations simulated include nonspherical terms in the earth's geopotential field, lunar and solar gravity, and solar radiation pressure. Objects simulated include large satellites, for which solar radiation pressure is insignificant, and small particles, for which solar radiation pressure is an important force. Results for large satellites are largely in agreement with previous GEO studies that used classical perturbation techniques. The orbit plane of GEO satellites placed in a stable plane orbit inclined approximately 7.3 deg to the equator experience very little precession, remaining always within 1.2 percent of their initial orientation. Solar radiation pressure generates two major effects on small particles: an orbital eccentricity oscillation anticipated from previous research, and an oscillation in orbital inclination.

Results of the First US Manned Orbital Space Flight

NASA Technical Reports Server (NTRS)

1962-01-01

The results of the first United States manned orbital space flight conducted on February 20, 1962 are presented. The prelaunch activities, spacecraft description, flight operations, flight data, and postflight analyses presented form a continuation of the information previously published for the two United States manned suborbital space flights conducted on May 5, 1961, and July 21, 1961, respectively, by the National Aeronautics and Space Administration.

Circumlunar Free-Return Cycler Orbits for a Manned Earth-Moon Space Station

NASA Technical Reports Server (NTRS)

Genova, Anthony L.; Aldrin, Buzz

2015-01-01

Multiple free-return circumlunar cycler orbits were designed to allow regular travel between the Earth and Moon by a manned space station. The presented cycler orbits contain circumlunar free-return "figure-8" segments and yield lunar encounters every month. Smaller space "taxi" vehicles can rendezvous with (and depart from) the cycling Earth-Moon space station to enter lunar orbit (and/or land on the lunar surface), return to Earth, or reach destinations including Earth-Moon L1 and L2 halo orbits, near-Earth objects (NEOs), Venus, and Mars. To assess the practicality of the selected orbits, relevant cycler characteristics (including (Delta)V maintenance requirements) are presented and compared.

Human Mars Mission: Launch Window from Earth Orbit. Pt. 1

NASA Technical Reports Server (NTRS)

Young, Archie

1999-01-01

The determination of orbital window characteristics is of major importance in the analysis of human interplanetary missions and systems. The orbital launch window characteristics are directly involved in the selection of mission trajectories, the development of orbit operational concepts, and the design of orbital launch systems. The orbital launch window problem arises because of the dynamic nature of the relative geometry between outgoing (departure) asymptote of the hyperbolic escape trajectory and the earth parking orbit. The orientation of the escape hyperbola asymptotic relative to earth is a function of time. The required hyperbola energy level also varies with time. In addition, the inertial orientation of the parking orbit is a function of time because of the perturbations caused by the Earth's oblateness. Thus, a coplanar injection onto the escape hyperbola can be made only at a point in time when the outgoing escape asymptote is contained by the plane of parking orbit. Even though this condition may be planned as a nominal situation, it will not generally represent the more probable injection geometry. The general case of an escape injection maneuver performed at a time other than the coplanar time will involve both a path angle and plane change and, therefore, a DELTA V penalty. Usually, because of the DELTA V penalty the actual departure injection window is smaller in duration than that determined by energy requirement alone. This report contains the formulation, characteristics, and test cases for five different launch window modes for Earth orbit. These modes are: (1) One impulsive maneuver from a Highly Elliptical Orbit (HEO) (2) Two impulsive maneuvers from a Highly Elliptical Orbit (HEO) (3) One impulsive maneuver from a Low Earth Orbit (LEO) (4) Two impulsive maneuvers from LEO (5) Three impulsive maneuvers from LEO.

Taurus lightweight manned spacecraft Earth orbiting vehicle

NASA Technical Reports Server (NTRS)

Chase, Kevin A.; Vandersall, Eric J.; Plotkin, Jennifer; Travisano, Jeffrey J.; Loveless, Dennis; Kaczmarek, Michael; White, Anthony G.; Est, Andy; Bulla, Gregory; Henry, Chris

1991-01-01

The Taurus Lightweight Manned Spacecraft (LMS) was developed by students of the University of Maryland's Aerospace Engineering course in Space Vehicle Design. That course required students to design an Alternative Manned Spacecraft (AMS) to augment or replace the Space Transportation System and meet the following design requirements: (1) launch on the Taurus Booster being developed by Orbital Sciences Corporation; (2) 99.9 percent assured crew survival rate; (3) technology cutoff data of 1 Jan. 1991; (4) compatibility with current space administration infrastructure; and (5) first flight by May 1995. The Taurus LMS design meets the above requirements and represents an initial step towards larger and more complex spacecraft. The Taurus LMS has a very limited application when compared to the Space Shuttle, but it demonstrates that the U.S. can have a safe, reliable, and low cost space system. The Taurus LMS is a short mission duration spacecraft designed to place one man into low earth orbit (LEO). The driving factor for this design was the low payload carrying capabilities of the Taurus Booster--1300 kg to a 300 km orbit. The Taurus LMS design is divided into six major design sections. The human factors system deals with the problems of life support and spacecraft cooling. The propulsion section contains the abort system, the Orbital Maneuvering System (OMS), the Reaction Control System (RCS), and power generation. The thermal protection systems and spacecraft structure are contained in the structures section. The avionics section includes navigation, attitude determination, data processing, communication systems, and sensors. The mission analysis section was responsible for ground processing and spacecraft astrodynamics. The systems integration section pulled the above sections together into one spacecraft and addressed costing and reliability.

Taurus Lightweight Manned Spacecraft Earth orbiting vehicle

NASA Technical Reports Server (NTRS)

Bosset, M.

1991-01-01

The Taurus Lightweight Manned Spacecraft (LMS) was developed by students of the University of Maryland's Aerospace Engineering course in Space Vehicle Design. That course required students to design an Alternative Manned Spacecraft (AMS) to augment or replace the Space Transportation System and meet the following design requirements: (1) launch on the Taurus Booster being developed by Orbital Sciences Corporation; (2) 99.9 percent assured crew survival rate; (3) technology cutoff date of 1 Jan. 1991; (4) compatibility with current space administration infrastructure; and (5) first flight by May 1995. The Taurus LMS design meets the above requirements and represents an initial step toward larger and more complex spacecraft. The Taurus LMS has a very limited application when compared to the space shuttle, but it demonstrates that the U.S. can have a safe, reliable, and low-cost space system. The Taurus LMS is a short mission duration spacecraft designed to place one man into low Earth orbit (LEO). The driving factor for this design was the low payload carrying capabilities of the Taurus Booster - 1300 kg to a 300-km orbit. The Taurus LMS design is divided into six major design sections. The Human Factors section deals with the problems of life support and spacecraft cooling. The Propulsion section contains the Abort System, the Orbital Maneuvering System (OMS), the Reaction Control System (RCS), and Power Generation. The thermal protection systems and spacecraft structure are contained in the Structures section. The Avionics section includes Navigation, Attitude Determination, Data Processing, Communication systems, and Sensors. The Mission Analysis section was responsible for ground processing and spacecraft astrodynamics. The Systems Integration Section pulled the above sections together into one spacecraft, and addressed costing and reliability.

Orbiter Return-To-Flight Entry Aeroheating

NASA Technical Reports Server (NTRS)

Campbell, Charles H.; Anderson, Brian; Bourland, Gary; Bouslog, Stan; Cassady, Amy; Horvath, Tom; Berry, Scott A.; Gnoffo, Peter; Wood, Bill; Reuther, James;

Orbital Sciences Pegasus XL Flight Simulation

NASA Image and Video Library

2007-02-28

Seen at Vandenberg Air Force Base in California is the fairing (foreground) for the Orbital Sciences Pegasus XL rocket. In the background is the third stage, under the clean room tent. The rocket is the launch vehicle for NASA's Aeronomy of Ice in the Mesosphere, or AIM, spacecraft. AIM is the seventh Small Explorers mission under NASA's Explorer Program. The program provides frequent flight opportunities for world-class scientific investigations from space within heliophysics and astrophysics. The AIM spacecraft will fly three instruments designed to study polar mesospheric clouds located at the edge of space, 50 miles above the Earth's surface in the coldest part of the planet's atmosphere. The mission's primary goal is to explain why these clouds form and what has caused them to become brighter and more numerous and appear at lower latitudes in recent years. AIM's results will provide the basis for the study of long-term variability in the mesospheric climate and its relationship to global climate change. AIM is scheduled to be mated to the Pegasus XL during the second week of April, after which final inspections will be conducted. Launch is scheduled for April 25.

Sub-orbital commercial Human space flight and informed consent in the United States

NASA Astrophysics Data System (ADS)

Carminati, Maria-Vittoria « Giugi »; Griffith, Doug; Campbell, Mark R.

2013-12-01

Commercial space flight is expected to rapidly develop in the near future. This will begin with sub-orbital missions and then progress to orbital flights. In the United States, technical informed consent of space flight participants is required by the commercial space flight operator for regulatory purposes. Additionally, though not required by U.S. regulation, the aerospace medicine professional involved in the medical screening of both space flight participants and crewmembers will be asked to assist operators in obtaining medical informed consent for liability purposes. The various US federal and state regulations regarding informed consent for sub-orbital commercial space flight are evolving and are unfamiliar to most aerospace medical professionals and are reviewed and discussed.

Human Exploration Missions Study Launch Window from Earth Orbit

NASA Technical Reports Server (NTRS)

Young, Archie

2001-01-01

The determination of orbital launch window characteristics is of major importance in the analysis of human interplanetary missions and systems. The orbital launch window characteristics are directly involved in the selection of mission trajectories, the development of orbit operational concepts, and the design of orbital launch systems. The orbital launch window problem arises because of the dynamic nature of the relative geometry between outgoing (departure) asymptote of the hyperbolic escape trajectory and the earth parking orbit. The orientation of the escape hyperbola asymptotic relative to earth is a function of time. The required hyperbola energy level also varies with time. In addition, the inertial orientation of the parking orbit is a function of time because of the perturbations caused by the Earth's oblateness. Thus, a coplanar injection onto the escape hyperbola can be made only at a point in time when the outgoing escape asymptote is contained by the plane of parking orbit. Even though this condition may be planned as a nominal situation, it will not generally represent the more probable injection geometry. The general case of an escape injection maneuver performed at a time other than the coplanar time will involve both a path angle and plane change and, therefore, a Delta(V) penalty. Usually, because of the Delta(V) penalty the actual departure injection window is smaller in duration than that determined by energy requirement alone. This report contains the formulation, characteristics, and test cases for five different launch window modes for Earth orbit. These modes are: (1) One impulsive maneuver from a Low Earth Orbit (LEO), (2) Two impulsive maneuvers from LEO, (3) Three impulsive maneuvers from LEO, (4) One impulsive maneuvers from a Highly Elliptical Orbit (HEO), (5) Two impulsive maneuvers from a Highly Elliptical Orbit (HEO) The formulation of these five different launch window modes provides a rapid means of generating realistic parametric

Feasibility analysis of cislunar flight using the Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Haynes, Davy A.

1991-01-01

A first order orbital mechanics analysis was conducted to examine the possibility of utilizing the Space Shuttle Orbiter to perform payload delivery missions to lunar orbit. In the analysis, the earth orbit of departure was constrained to be that of Space Station Freedom. Furthermore, no enhancements of the Orbiter's thermal protection system were assumed. Therefore, earth orbit insertion maneuvers were constrained to be all propulsive. Only minimal constraints were placed on the lunar orbits and no consideration was given to possible landing sites for lunar surface payloads. The various phases and maneuvers of the mission are discussed for both a conventional (Apollo type) and an unconventional mission profile. The velocity impulses needed, and the propellant masses required are presented for all of the mission maneuvers. Maximum payload capabilities were determined for both of the mission profiles examined. In addition, other issues relating to the feasibility of such lunar shuttle missions are discussed. The results of the analysis indicate that the Shuttle Orbiter would be a poor vehicle for payload delivery missions to lunar orbit.

Hypersonic Navier-Stokes Comparisons to Orbiter Flight Data

NASA Technical Reports Server (NTRS)

Candler, Graham V.; Campbell, Charles H.

2010-01-01

During the STS-119 flight of Space Shuttle Discovery, two sets of surface temperature measurements were made. Under the HYTHIRM program3 quantitative thermal images of the windward side of the Orbiter with a were taken. In addition, the Boundary Layer Transition Flight Experiment 4 made thermocouple measurements at discrete locations on the Orbiter wind side. Most of these measurements were made downstream of a surface protuberance designed to trip the boundary layer to turbulent flow. In this paper, we use the US3D computational fluid dynamics code to simulate the Orbiter flow field at conditions corresponding to the STS-119 re-entry. We employ a standard two-temperature, five-species finite-rate model for high-temperature air, and the surface catalysis model of Stewart.1 This work is similar to the analysis of Wood et al . 2 except that we use a different approach for modeling turbulent flow. We use the one-equation Spalart-Allmaras turbulence model8 with compressibility corrections 9 and an approach for tripping the boundary layer at discrete locations. In general, the comparison between the simulations and flight data is remarkably good

The Orbital Evolution of Near-Earth Asteroid 3753

NASA Astrophysics Data System (ADS)

Wiegert, Paul A.; Innanen, Kimmo A.; Mikkola, Seppo

1998-06-01

Asteroid 3753 (1986 TO) is in a 1:1 mean motion resonance with Earth, on a complex horseshoe-type orbit. Numerical experiments are performed to determine its medium-term stability and the means by which it may have entered its current orbit. Though 3753 moves primarily under the influence of the Sun and Earth, the giant planets (and Jupiter especially) play an important role by influencing, through torque-induced precession, the position of the asteroid's nodes. Variations in the nodal distance strongly affect the interaction of 3753 with Earth and may change or destroy the horseshoe-like behavior currently seen. This precession of the nodes provides a mechanism for placing minor planets into, or removing them from, a variety of horseshoe-type orbits. The chaotic nature of this asteroid's orbit makes predictions difficult on timescales longer than its Lyapunov time (~150 yr); therefore, ensembles of particles on orbits near that of 3753 are considered. The asteroid has a high probability of passing close to Venus and/or Mars on 10^4 yr timescales, pointing to a dynamical age much shorter than that of the solar system.

Formation Flying in Earth, Libration, and Distant Retrograde Orbits

NASA Technical Reports Server (NTRS)

Folta, David C.

2004-01-01

This slide presentation examines the current and future state of formation flying, LEO formations, control strategies for flight in the vicinity of the libration points, and distant retrograde orbit formations. This discussion of LEO formations includes background on perturbation theory/accelerations and LEO formation flying. The discussion of strategies for formation flight in the vicinity of the libration points includes libration missions and natural and controlled libration orbit formations. A reference list is included.

Analysis of orbit determination from Earth-based tracking for relay satellites in a perturbed areostationary orbit

NASA Astrophysics Data System (ADS)

Romero, P.; Pablos, B.; Barderas, G.

2017-07-01

Areostationary satellites are considered a high interest group of satellites to satisfy the telecommunications needs of the foreseen missions to Mars. An areostationary satellite, in an areoequatorial circular orbit with a period of 1 Martian sidereal day, would orbit Mars remaining at a fixed location over the Martian surface, analogous to a geostationary satellite around the Earth. This work addresses an analysis of the perturbed orbital motion of an areostationary satellite as well as a preliminary analysis of the aerostationary orbit estimation accuracy based on Earth tracking observations. First, the models for the perturbations due to the Mars gravitational field, the gravitational attraction of the Sun and the Martian moons, Phobos and Deimos, and solar radiation pressure are described. Then, the observability from Earth including possible occultations by Mars of an areostationary satellite in a perturbed areosynchronous motion is analyzed. The results show that continuous Earth-based tracking is achievable using observations from the three NASA Deep Space Network Complexes in Madrid, Goldstone and Canberra in an occultation-free scenario. Finally, an analysis of the orbit determination accuracy is addressed considering several scenarios including discontinuous tracking schedules for different epochs and different areoestationary satellites. Simulations also allow to quantify the aerostationary orbit estimation accuracy for various tracking series durations and observed orbit arc-lengths.

Space flight visual simulation.

PubMed

Xu, L

1985-01-01

In this paper, based on the scenes of stars seen by astronauts in their orbital flights, we have studied the mathematical model which must be constructed for CGI system to realize the space flight visual simulation. Considering such factors as the revolution and rotation of the Earth, exact date, time and site of orbital injection of the spacecraft, as well as its orbital flight and attitude motion, etc., we first defined all the instantaneous lines of sight and visual fields of astronauts in space. Then, through a series of coordinate transforms, the pictures of the scenes of stars changing with time-space were photographed one by one mathematically. In the procedure, we have designed a method of three-times "mathematical cutting." Finally, we obtained each instantaneous picture of the scenes of stars observed by astronauts through the window of the cockpit. Also, the dynamic conditions shaded by the Earth in the varying pictures of scenes of stars could be displayed.

Condition of the upper atmosphere of the Earth at the final stage of flight manned orbital facility (MOF) "Mir". The modeling description

NASA Astrophysics Data System (ADS)

Boyarchuk, K. A.; Ivanov-Kholodny, G. S.; Kolomiitsev, O. P.; Surotkin, V. A.

At flooding MOF ``Mir'' the information on forecasting a condition of the upper atmosphere was used. The forecast was carried out on the basis of numerical model of an atmosphere, which was developed in IZMIRAN. This model allows reproducing and predicting a situation in an Earth space, in an atmosphere and an ionosphere, along an orbit of flight of a space vehicle in the various periods of solar-geophysical conditions. Thus preliminary forecasting solar and geomagnetic activity was carried out on the basis of an individual technique. Before the beginning of operation on flooding MOF ``Mir'' it was found out, that solar activity began to accrue catastrophically. The account of the forecast of its development has forced to speed up the moment of flooding to avoid dangerous development of events. It has allowed minimizing a risk factor - ``Mir'' was flooded successful in the commanded area of Pacific Ocean.

Essentials for Team Based Rehearsals and the Differences Between Earth Orbiting and Deep Space Missions

NASA Technical Reports Server (NTRS)

Gomez-Rosa, Carlos; Cifuentes, Juan; Wasiak, Francis; Alfonzo, Agustin

2015-01-01

The mission readiness environment is where spacecraft and ground systems converge to form the entire as built flight system for the final phase of operationally-themed testing. For most space missions, this phase starts between nine to twelve months prior to the planned launch. In the mission readiness environment, the goal is to perform sufficient testing to exercise the flight teams and systems through all mission phases in order to demonstrate that all elements are ready to support. As part of the maturation process, a mission rehearsal program is introduced to focus on team processes within the final flight system, in a more realistic operational environment. The overall goal for a mission rehearsal program is to: 1) ensure all flight system elements are able to meet mission objectives as a cohesive team; 2) reduce the risk in space based operations due to deficiencies in people, processes, procedures, or systems; and 3) instill confidence in the teams that will execute these first time flight activities. A good rehearsal program ensures critical events are exercised, discovers team or flight system nuances whose impact were previously unknown, and provides a real-time environment in which to interact with the various teams and systems. For flight team members, the rehearsal program provides experience and training in the event of planned (or unplanned) flight contingencies. To preserve the essence for team based rehearsals, this paper will explore the important elements necessary for a successful rehearsal program, document differences driven by Earth Orbiting (Aqua, Aura, Suomi-National Polar-orbiting Partnership (NPP)) and Deep Space missions (New Horizons, Mars Atmosphere and Volatile EvolutioN (MAVEN)) and discuss common challenges to both mission types. In addition, large scale program considerations and enhancements or additional steps for developing a rehearsal program will also be considered. For NASA missions, the mission rehearsal phase is a key

Some Unknown Pages of the Living Organisms' First Orbital Flight

NASA Astrophysics Data System (ADS)

Malashenkov, D. C.

2002-01-01

The successful creation of ballistic rockets in USSR has allowed at the end of 1953 to make a real task of delivery of a payload into the Earth's orbit. In March 1954 during the meeting in the Academy of Sciences of USSR, the basic research problems conducted by means of artificial satellites of the Earth were determined. In May, 1954 S. Korolev has sent to Government of the USSR the report with the offer of creation the space satellites on the basis of intercontinental ballistic rocket -7 developed by him. It was the first time when the idea about possibility of interplanetary flights was stated in the official document. In August 1954 Council of Ministers of the USSR had ratified the submitted offers and have entrusted to work over scientific and theoretical problems of space flight. In the beginning of 1956 the Korolev's United Design Bureau was officially entrusted the creation and launch of undirected research satellite named "Object D" weighing 1.000-1.400 kg in 1957-1958. The main scientific management and development of scientific equipment was assigned to a commission of the Academy of Sciences of the USSR under the direction of . Keldysh. The measurement of parameters of the atmosphere, corpuscular radiation of the Sun, magnetic fields, space radiation etc. was planned during the "Object D" flight. The successful performance in the middle of 1956 of the second series of launches of geophysical rockets has allowed to gain a large volume of the information about parameters of physiological functions and behavior of animals in conditions of flight. For enlargement of these works the laboratory of V. Yazdovsky in the Institute of aviation medicine was extended to a department, the large group of the new employees, including V. Antipov, . Baevsky, I. Balakhovsky, B. Buylov, . Genin, O. Gazenko, A. Gurdjian, I. Kasyan, A. Kotovskaya, E..Yuganov, . Shepelev and others came to the department. But, owing to the delay of development of the scientific equipment for

STS-30 aft flight deck onboard view of overhead window, Earth limb, cow photo

NASA Technical Reports Server (NTRS)

1989-01-01

Since the beginning of manned space travel, astronauts have taken onboard with them items of person sentiment. During STS-30 onboard Atlantis, Orbiter Vehicle (OV) 104, Mission Specialist Mark C. Lee brought along a photograph of a cow. The photo testifies to his background as one reared on a Wisconsin farm and is displayed on aft flight deck alongside an overhead window. Outside the window, some 160 nautical miles away, is the cloud-covered Earth surface.

Direct Data Distribution From Low-Earth Orbit

NASA Technical Reports Server (NTRS)

Budinger, James M.; Fujikawa, Gene; Kunath, Richard R.; Nguyen, Nam T.; Romanofsky, Robert R.; Spence, Rodney L.

1997-01-01

NASA Lewis Research Center (LeRC) is developing the space and ground segment technologies necessary to demonstrate a direct data distribution (1)3) system for use in space-to-ground communication links from spacecraft in low-Earth orbit (LEO) to strategically located tracking ground terminals. The key space segment technologies include a K-band (19 GHz) MMIC-based transmit phased array antenna, and a multichannel bandwidth- and power-efficient digital encoder/modulate with an aggregate data rate of 622 Mb/s. Along with small (1.8 meter), low-cost tracking terminals on the ground, the D3 system enables affordable distribution of data to the end user or archive facility through interoperability with commercial terrestrial telecommunications networks. The D3 system is applicable to both government and commercial science and communications spacecraft in LEO. The features and benefits of the D3 system concept are described. Starting with typical orbital characteristics, a set of baseline requirements for representative applications is developed, including requirements for onboard storage and tracking terminals, and sample link budgets are presented. Characteristics of the transmit array antenna and digital encoder/modulator are described. The architecture and components of the tracking terminal are described, including technologies for the next generation terminal. Candidate flights of opportunity for risk mitigation and space demonstration of the D3 features are identified.

A Comparison of Damaging Meteoroid and Orbital Debris Fluxes in Earth Orbit

NASA Technical Reports Server (NTRS)

Cooke, William; Matney, Mark; Moorhead, Althea V.; Vavrin, Andrew

2017-01-01

Low Earth orbit is populated with a substantial amount of orbital debris, and it is usually assumed that the flux from these objects contributes to most of the hypervelocity particle risk to spacecraft in this region. The meteoroid flux is known to be dominant at very low altitudes (<300 km), where atmospheric drag rapidly removes debris, and at very high altitudes beyond GEO (geostationary), where debris is practically non-existent. The vagueness of these boundaries has prompted this work, in which we compare the fluxes of meteoroids and orbital debris capable of penetrating a millimeter thick aluminum plate for circular orbits with altitudes ranging from the top of the atmosphere to 100,000 km. The outputs from the latest NASA debris and meteoroid models, ORDEM 3.0 and MEMR2, are combined with the modified Cour-Palais ballistic limit equation to make a realistic evaluation of the damage-capable particle fluxes, thereby establishing the relative contributions of hazardous debris and meteoroids in near Earth space.

ISS15A Flight Control Team in FCR-1 Orbit 1 - Flight Director Kwatsi Alibaruho

NASA Image and Video Library

2009-03-20

JSC2009-E-060959 (20 March 2009) --- The members of the STS-119/15A ISS Orbit 1 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA’s Johnson Space Center. Flight director Kwatsi Alibaruho (right) is visible on the front row.

ISS ULF2 Flight Control Team in FCR-1 - Orbit 3 - Flight Director David Korth

NASA Image and Video Library

2009-03-20

JSC2009-E-061164 (20 March 2009) --- The members of the STS-119/15A ISS Orbit 3 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA’s Johnson Space Center. Flight director David Korth (right) is visible on the front row.

A Free-Return Earth-Moon Cycler Orbit for an Interplanetary Cruise Ship

NASA Technical Reports Server (NTRS)

Genova, Anthony L.; Aldrin, Buzz

2015-01-01

A periodic circumlunar orbit is presented that can be used by an interplanetary cruise ship for regular travel between Earth and the Moon. This Earth-Moon cycler orbit was revealed by introducing solar gravity and modest phasing maneuvers (average of 39 m/s per month) which yields close-Earth encounters every 7 or 10 days. Lunar encounters occur every 26 days and offer the chance for a smaller craft to depart the cycler and enter lunar orbit, or head for a Lagrange point (e.g., EM-L2 halo orbit), distant retrograde orbit (DRO), or interplanetary destination such as a near-Earth object (NEO) or Mars. Additionally, return-to-Earth abort options are available from many points along the cycling trajectory.

FROM ORDER TO CHAOS IN EARTH SATELLITE ORBITS

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

Gkolias, Ioannis; Gachet, Fabien; Daquin, Jérôme

We consider Earth satellite orbits in the range of semimajor axes where the perturbing effects of Earth’s oblateness and lunisolar gravity are of comparable order. This range covers the medium-Earth orbits (MEO) of the Global Navigation Satellite Systems and the geosynchronous orbits (GEO) of the communication satellites. We recall a secular and quadrupolar model, based on the Milankovitch vector formulation of perturbation theory, which governs the long-term orbital evolution subject to the predominant gravitational interactions. We study the global dynamics of this two-and-a-half degrees-of-freedom Hamiltonian system by means of the fast Lyapunov indicator (FLI), used in a statistical sense. Specifically,more » we characterize the degree of chaoticity of the action space using angle-averaged normalized FLI maps, thereby overcoming the angle dependencies of the conventional stability maps. Emphasis is placed upon the phase-space structures near secular resonances, which are of primary importance to the space debris community. We confirm and quantify the transition from order to chaos in MEO, stemming from the critical inclinations and find that highly inclined GEO orbits are particularly unstable. Despite their reputed normality, Earth satellite orbits can possess an extraordinarily rich spectrum of dynamical behaviors and, from a mathematical perspective, have all the complications that make them very interesting candidates for testing the modern tools of chaos theory.« less

From Order to Chaos in Earth Satellite Orbits

NASA Astrophysics Data System (ADS)

Gkolias, Ioannis; Daquin, Jérôme; Gachet, Fabien; Rosengren, Aaron J.

2016-11-01

We consider Earth satellite orbits in the range of semimajor axes where the perturbing effects of Earth’s oblateness and lunisolar gravity are of comparable order. This range covers the medium-Earth orbits (MEO) of the Global Navigation Satellite Systems and the geosynchronous orbits (GEO) of the communication satellites. We recall a secular and quadrupolar model, based on the Milankovitch vector formulation of perturbation theory, which governs the long-term orbital evolution subject to the predominant gravitational interactions. We study the global dynamics of this two-and-a-half degrees-of-freedom Hamiltonian system by means of the fast Lyapunov indicator (FLI), used in a statistical sense. Specifically, we characterize the degree of chaoticity of the action space using angle-averaged normalized FLI maps, thereby overcoming the angle dependencies of the conventional stability maps. Emphasis is placed upon the phase-space structures near secular resonances, which are of primary importance to the space debris community. We confirm and quantify the transition from order to chaos in MEO, stemming from the critical inclinations and find that highly inclined GEO orbits are particularly unstable. Despite their reputed normality, Earth satellite orbits can possess an extraordinarily rich spectrum of dynamical behaviors and, from a mathematical perspective, have all the complications that make them very interesting candidates for testing the modern tools of chaos theory.

Space radiation dosimetry in low-Earth orbit and beyond.

PubMed

Benton, E R; Benton, E V

2001-09-01

Space radiation dosimetry presents one of the greatest challenges in the discipline of radiation protection. This is a result of both the highly complex nature of the radiation fields encountered in low-Earth orbit (LEO) and interplanetary space and of the constraints imposed by spaceflight on instrument design. This paper reviews the sources and composition of the space radiation environment in LEO as well as beyond the Earth's magnetosphere. A review of much of the dosimetric data that have been gathered over the last four decades of human space flight is presented. The different factors affecting the radiation exposures of astronauts and cosmonauts aboard the International Space Station (ISS) are emphasized. Measurements made aboard the Mir Orbital Station have highlighted the importance of both secondary particle production within the structure of spacecraft and the effect of shielding on both crew dose and dose equivalent. Roughly half the dose on ISS is expected to come from trapped protons and half from galactic cosmic rays (GCRs). The dearth of neutron measurements aboard LEO spacecraft and the difficulty inherent in making such measurements have led to large uncertainties in estimates of the neutron contribution to total dose equivalent. Except for a limited number of measurements made aboard the Apollo lunar missions, no crew dosimetry has been conducted beyond the Earth's magnetosphere. At the present time we are forced to rely on model-based estimates of crew dose and dose equivalent when planning for interplanetary missions, such as a mission to Mars. While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars. c2001 Elsevier Science B.V. All rights reserved.

Orbital and Landing Operations at Near-Earth

NASA Technical Reports Server (NTRS)

Scheeres, D. J.

1995-01-01

Orbital and landing operations about near-Earth asteroids are different than classical orbital operations about large bodies. The major differences lie with the small mass of the asteroid, the lower orbital velocities, the larger Solar tide and radiation pressure perturbations, the irregular shape of the asteroid and the potential for non-uniform rotation of the asteroid. These differences change the nature of orbits about an asteroid to where it is often common to find trajectories that evolve from stable, near-circular orbits to crashing or escaping orbits in a matter of days. The understanding and control of such orbits is important if a human or robotic presence at asteroids is to be commonplace in the future.

Degradation of Spacesuit Fabrics in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Gaier, James R.; Baldwin, Sammantha M.; Folz, Angela D.; Waters, Deborah L.; McCue, Terry R.; Jaworske, Donald A.; Clark, Gregory W.; Rogers, Kerry J.; Batman, Brittany; Bruce, John;

Earth Science

NASA Image and Video Library

1976-01-01

The LAGEOS I (Laser Geodynamics Satellite) was developed and launched by the Marshall Space Flight Center on May 4, 1976 from Vandenberg Air Force Base, California . The two-foot diameter satellite orbited the Earth from pole to pole and measured the movements of the Earth's surface.

A passive satellite deorbiting strategy for medium earth orbit using solar radiation pressure and the J2 effect

NASA Astrophysics Data System (ADS)

Lücking, Charlotte; Colombo, Camilla; McInnes, Colin R.

2012-08-01

The growing population of space debris poses a serious risk to the future of space flight. To effectively manage the increase of debris in orbit, end-of life disposal has become a key requirement for future missions. This poses a challenge for Medium Earth Orbit (MEO) spacecraft which require a large Δv to re-enter the atmosphere or reach the geostationary graveyard orbit. This paper further explores a passive strategy based on the joint effects of solar radiation pressure and the Earth's oblateness acting on a high area-to-mass-ratio object. The concept was previously presented as an analytical planar model. This paper uses a full 3D model to validate the analytical results numerically for equatorial circular orbits first, then investigating higher inclinations. It is shown that for higher inclinations the initial position of the Sun and right ascension of the ascending node become increasingly important. A region of very low required area-to-mass-ratio is identified in the parameter space of semi-major axis and inclination which occurs for altitudes below 10,000 km.

STS-79 crew on flight deck after launch

NASA Image and Video Library

1996-10-29

STS079-348-004 (16 Sept. 1996) --- Soon after the space shuttle Atlantis completed its rocket mode ascent to Earth-orbit, astronaut Terrence W. Wilcutt, pilot, begins to ready the Orbiter for ten days of orbiting Earth by activating switches on the flight deck's right overhead panel. Though the launch was a nocturnal one, the crew experienced its first sunrise just after Atlantis achieved its orbital posture.

Earth orbital experiment program and requirements study, volume 1, sections 1 - 6

NASA Technical Reports Server (NTRS)

1971-01-01

A reference manual for planners of manned earth-orbital research activity is presented. The manual serves as a systems approach to experiment and mission planning based on an integrated consideration of candidate research programs and the appropriate vehicle, mission, and technology development requirements. Long range goals and objectives for NASA activities during the 1970 to 1980 time period are analyzed. The useful and proper roles of manned and automated spacecraft for implementing NASA experiments are described. An integrated consideration of NASA long range goals and objectives, the system and mission requirements, and the alternative implementation plans are developed. Specific areas of investigation are: (1) manned space flight requirements, (2) space biology, (3) spaceborne astronomy, (4) space communications and navigation, (5) earth observation, (6) supporting technology development requirements, (7) data management system matrices, (8) instrumentation matrices, and (9) biotechnology laboratory experiments.

Orbital Express Advanced Video Guidance Sensor: Ground Testing, Flight Results and Comparisons

NASA Technical Reports Server (NTRS)

Pinson, Robin M.; Howard, Richard T.; Heaton, Andrew F.

2008-01-01

Orbital Express (OE) was a successful mission demonstrating automated rendezvous and docking. The 2007 mission consisted of two spacecraft, the Autonomous Space Transport Robotic Operations (ASTRO) and the Next Generation Serviceable Satellite (NEXTSat) that were designed to work together and test a variety of service operations in orbit. The Advanced Video Guidance Sensor, AVGS, was included as one of the primary proximity navigation sensors on board the ASTRO. The AVGS was one of four sensors that provided relative position and attitude between the two vehicles. Marshall Space Flight Center was responsible for the AVGS software and testing (especially the extensive ground testing), flight operations support, and analyzing the flight data. This paper briefly describes the historical mission, the data taken on-orbit, the ground testing that occurred, and finally comparisons between flight data and ground test data for two different flight regimes.

third "free flight" of Shuttle Orbiter 101 Spacecraft

NASA Image and Video Library

1977-09-23

S77-28542 (23 Sept 1977) --- The shuttle Orbiter 101 "Enterprise" separates from the NASA 747 carrier aircraft during the third free flight of the Shuttle Approach and Landing Tests (ALT) conducted on September 23, 1977, at the Dryden Flight Research Center (DFRC) in Southern California. The vehicle, with astronauts Fred W. Haise Jr., commander, and C. Gordon Fullerton, pilot, remained in unpowered flight for five-minutes and 34-seconds before landing on the desert land of Edwards Air Force Base.

New approaches for tracking earth orbiters using modified GPS ground receivers

NASA Technical Reports Server (NTRS)

Lichten, S. M.; Young, L. E.; Nandi, S.; Haines, B. J.; Dunn, C. E.; Edwards, C. D.

1993-01-01

A Global Positioning System (GPS) flight receiver provides a means to precisely determine orbits for satellites in low to moderate altitude orbits. Above a 5000-km altitude, however, relatively few GPS satellites are visible. New approaches to orbit determination for satellites at higher altitudes could reduce DSN antenna time needed to provide navigation and orbit determination support to future missions. Modification of GPS ground receivers enables a beacon from the orbiter to be tracked simultaneously with GPS data. The orbit accuracy expected from this GPS-like tracking (GLT) technique is expected to be in the range of a few meters or better for altitudes up to 100,000 km with a global ground network. For geosynchronous satellites, however, there are unique challenges due to geometrical limitations and to the lack of strong dynamical signature in tracking data. We examine two approaches for tracking the Tracking and Data Relay Satellite System (TDRSS) geostationary orbiters. One uses GLT with a global network; the other relies on a small 'connected element' ground network with a distributed clock for short-baseline differential carrier phase (SB Delta Phi). We describe an experiment planned for late 1993, which will combine aspects of both GLT and SB Delta Phi, to demonstrate a new approach for tracking the Tracking and Data Relay Satellites (TDRSs) that offers a number of operationally convenient and attractive features. The TDRS demonstration will be in effect a proof-of-concept experiment for a new approach to tracking spacecraft which could be applied more generally to deep-space as well as near-Earth regimes.

Effects of the low Earth orbital environment on spacecraft materials

NASA Technical Reports Server (NTRS)

Leger, L. J.

1986-01-01

It is evident from space flights during the last three years that the low Earth orbital (LEO) environment interacts with spacecraft surfaces in significant ways. One manifestation of these interactions is recession of, in particular, organic-polymer-based surfaces presumably due to oxidation by atomic oxygen, the major component of the LEO environment. Three experiments have been conducted on Space Shuttle flights 5, 8 and 41-G to measure reaction rates and the effects of various parameters on reaction rates. Surface recession on these flights indicates reaction efficiencies approximately 3 x 10(-24) cu cm/atoms for unfilled organic polymers. Of the metals, silver and osmium are very reactive. Effects on spacecraft or experiment surfaces can be evaluated using the derived reaction efficiencies and a definition of the total exposure to atomic oxygen. This exposure is obtained using an ambient density model, solar activity data and spacecraft parameters of altitude, attitude and operational date. Oxygen flux on a given surface is obtained from the ambient density and spacecraft velocity and can then be integrated to provide the total exposure or fluence. Such information can be generated using simple computational programs and can be converted to various formats. Overall, the extent of damage is strongly dependent on the type of surface and total exposure time.

Health management and controls for Earth-to-orbit propulsion systems

NASA Astrophysics Data System (ADS)

Bickford, R. L.

1995-03-01

Avionics and health management technologies increase the safety and reliability while decreasing the overall cost for Earth-to-orbit (ETO) propulsion systems. New ETO propulsion systems will depend on highly reliable fault tolerant flight avionics, advanced sensing systems and artificial intelligence aided software to ensure critical control, safety and maintenance requirements are met in a cost effective manner. Propulsion avionics consist of the engine controller, actuators, sensors, software and ground support elements. In addition to control and safety functions, these elements perform system monitoring for health management. Health management is enhanced by advanced sensing systems and algorithms which provide automated fault detection and enable adaptive control and/or maintenance approaches. Aerojet is developing advanced fault tolerant rocket engine controllers which provide very high levels of reliability. Smart sensors and software systems which significantly enhance fault coverage and enable automated operations are also under development. Smart sensing systems, such as flight capable plume spectrometers, have reached maturity in ground-based applications and are suitable for bridging to flight. Software to detect failed sensors has reached similar maturity. This paper will discuss fault detection and isolation for advanced rocket engine controllers as well as examples of advanced sensing systems and software which significantly improve component failure detection for engine system safety and health management.

Sub-orbital flights, a starting point for space tourism

NASA Astrophysics Data System (ADS)

Gaubatz, William A.

2002-07-01

While there is a growing awareness and interest by the general public in space travel neither the market nor the infrastructure exist to make a commercial space tourism business an attractive risk venture. In addition there is much to be learned about how the general public will respond to space flights and what physiological and psychological needs must be met to ensure a pleasurable as well as adventurous experience. Sub-orbital flights offer an incremental approach to develop the market and the infrastructure, demonstrate the safety of space flight, obtain real flight information regarding the needs of general public passengers and demonstrate the profitability of space tourism. This paper will summarize some of the system, operations, and financial aspects of creating a sub-orbital space tourism business as a stepping-stone to public space travel. A sample business case will be reviewed and impacts of markets, operations and vehicle costs and lifetimes will be assessed.

STS-109 Flight Control Team Photo in WFCR - Orbit 2 with Flight Director Tony Ceccaci.

NASA Image and Video Library

2002-03-05

JSC2002-00574 (5 March 2002) --- The members of the STS-109 Orbit 2 Team pose for a group portrait in the shuttle flight control room (WFCR) in Houston's Mission Control Center (MCC). Flight director Tony Ceccacci holds the STS-109 mission logo.

Design and "As Flown" Radiation Environments for Materials in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Minow, Joseph; McWilliams, Brett; Altstatt, Richard; Koontz, Steven

2006-01-01

A conservative design approach was adopted by the International Space Station Program for specifying total ionizing radiation dose requirements for use in selecting and qualifying materials for construction of the International Space Station. The total ionizing dose design environment included in SSP 30512 Space Station Ionizing Radiation Design Environment is based on trapped proton and electron fluence derived from the solar maximum versions of the AE-8 and AP-8 models, respectively, specified for a circular orbit at 500 km altitude and 51.7 degree inclination. Since launch, the range of altitudes utilized for Space Station operations vary from a minimum of approximately 330 km to a maximum of approximately 405 km with a mean operational altitude less than 400 km. The design environment, therefore, overestimates the radiation environment because the particle flux in the South Atlantic Anomaly is the primary contributor to radiation dose in low Earth orbit and flux within the Anomaly is altitude dependent. In addition, a 2X multiplier is often applied to the design environment to cover effects from the contributions of galactic cosmic rays, solar energetic particle events, geomagnetic storms, and uncertainties in the trapped radiation models which are not explicitly included in the design environment. Application of this environment may give radiation dose overestimates on the order of 1OX to 30X for materials exposed to the space environment, suggesting that materials originally qualified for ten year exposures on orbit may be used for longer periods without replacement. In this paper we evaluate the "as flown" radiation environments derived from historical records of the ISS flight trajectory since launch and compare the results with the SSP 30512 design environment to document the magnitude of the radiation dose overestimate provided by the design environment. "As flown" environments are obtained from application of the AE-8/AP-8 trapped particle models along

Regional positioning using a low Earth orbit satellite constellation

NASA Astrophysics Data System (ADS)

Shtark, Tomer; Gurfil, Pini

2018-02-01

Global and regional satellite navigation systems are constellations orbiting the Earth and transmitting radio signals for determining position and velocity of users around the globe. The state-of-the-art navigation satellite systems are located in medium Earth orbits and geosynchronous Earth orbits and are characterized by high launching, building and maintenance costs. For applications that require only regional coverage, the continuous and global coverage that existing systems provide may be unnecessary. Thus, a nano-satellites-based regional navigation satellite system in Low Earth Orbit (LEO), with significantly reduced launching, building and maintenance costs, can be considered. Thus, this paper is aimed at developing a LEO constellation optimization and design method, using genetic algorithms and gradient-based optimization. The preliminary results of this study include 268 LEO constellations, aimed at regional navigation in an approximately 1000 km × 1000 km area centered at the geographic coordinates [30, 30] degrees. The constellations performance is examined using simulations, and the figures of merit include total coverage time, revisit time, and geometric dilution of precision (GDOP) percentiles. The GDOP is a quantity that determines the positioning solution accuracy and solely depends on the spatial geometry of the satellites. Whereas the optimization method takes into account only the Earth's second zonal harmonic coefficient, the simulations include the Earth's gravitational field with zonal and tesseral harmonics up to degree 10 and order 10, Solar radiation pressure, drag, and the lunisolar gravitational perturbation.

View of Mission Control during Apollo 9 earth orbital mission

NASA Image and Video Library

1969-03-03

S69-26301 (March 1969) --- Overall view of the Mission Operations Control Room in the Mission Control Center, Building 30, during the Apollo 9 Earth-orbital mission. When this photograph was taken a live television transmission was being received from Apollo 9 as it orbited Earth.

An Investigation of Low Earth Orbit Internal Charging

NASA Technical Reports Server (NTRS)

Parker, Linda Neergaard; Minow, Joseph; Willis, Emily

2014-01-01

Internal charging is not generally considered a threat in low Earth orbit due to the relatively short exposure times and low flux of electrons with energies of a few MeV encountered in typical orbits. There are configurations, however, where insulators and ungrounded conductors used on the outside of a spacecraft hull may charge when exposed to much lower energy electrons of some 100's keV in a process that is better characterized as internal charging than surface charging. We investigate the conditions required for this internal charging process to occur in low Earth orbit using a one-dimensional charging model and evaluate the environments for which the process may be a threat to spacecraft.

Plasma Flowfields Around Low Earth Orbit Objects: Aerodynamics to Underpin Orbit Predictions

NASA Astrophysics Data System (ADS)

Capon, Christopher; Boyce, Russell; Brown, Melrose

2016-07-01

Interactions between orbiting bodies and the charged space environment are complex. The large variation in passive body parameters e.g. size, geometry and materials, makes the plasma-body interaction in Low Earth Orbit (LEO) a region rich in fundamental physical phenomena. The aerodynamic interaction of LEO orbiting bodies with the neutral environment constitutes the largest non-conservative force on the body. However in general, study of the LEO plasma-body interaction has not been concerned with external flow physics, but rather with the effects on surface charging. The impact of ionospheric flow physics on the forces on space debris (and active objects) is not well understood. The work presented here investigates the contribution that plasma-body interactions have on the flow structure and hence on the total atmospheric force vector experienced by a polar orbiting LEO body. This work applies a hybrid Particle-in-Cell (PIC) - Direct Simulation Monte Carlo (DSMC) code, pdFoam, to self-consistently model the electrostatic flowfield about a cylinder with a uniform, fixed surface potential. Flow conditions are representative of the mean conditions experienced by the Earth Observing Satellite (EOS) based on the International Reference Ionosphere model (IRI-86). The electron distribution function is represented by a non-linear Boltzmann electron fluid and ion gas-surface interactions are assumed to be that of a neutralising, conducting, thermally accommodating solid wall with diffuse reflections. The variation in flowfield and aerodynamic properties with surface potential at a fixed flow condition is investigated, and insight into the relative contributions of charged and neutral species to the flow physics experienced by a LEO orbiting body is provided. This in turn is intended to help improve the fidelity of physics-based orbit predictions for space debris and other near-Earth space objects.

A Comparison of Damaging Meteoroid and Orbital Debris Fluxes in Earth Orbit

NASA Technical Reports Server (NTRS)

Cooke, William; Matney, Mark; Moorhead, Althea V.; Vavrin, Andrew

2017-01-01

Low Earth orbit is populated with a substantial amount of orbital debris, and it is usually assumed that the flux from these objects contributes to most of the hypervelocity particle risk to spacecraft in this region. The meteoroid flux is known to be dominant at very low altitudes (less than 300 km), where atmospheric drag rapidly removes debris, and at very high altitudes (beyond geostationary), where debris is practically non-existent. The vagueness of these boundaries and repeated questions from spacecraft projects have prompted this work, in which we compare the fluxes of meteoroids and orbital debris capable of producing a millimeter-deep crater in aluminum for circular orbits with altitudes ranging from the top of the atmosphere to 100,000 km. The outputs from the latest NASA debris and meteoroid models, ORDEM 3.0 and MEMR2, are combined with the modified Cour-Palais ballistic limit equation to make a realistic evaluation of the damage-capable particle fluxes, thereby establishing the relative contributions of hazardous debris and meteoroids throughout near-Earth space.

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

May, Todd

2012-01-01

The National Aeronautics and Space Administration s (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit in an austere economic climate. This fact drives the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history. To arrive at the current SLS plan, government and industry experts carefully analyzed hundreds of architecture options and arrived at the one clear solution to stringent requirements for safety, affordability, and sustainability over the decades that the rocket will be in operation. This paper will explore ways to fit this major development within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017. It will explain the SLS Program s long-range plan to keep the budget within bounds, yet evolve the 70 metric ton (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through a competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface over 4 decades ago. Astronauts train for long-duration voyages on the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. NASA is refining its mission manifest, guided by U.S. Space Policy and the Global Exploration Roadmap. Launching the Orion Multi-Purpose Cargo Vehicle s first autonomous certification flight in 2017, followed by a crewed flight in 2021, the SLS will offer a robust way to transport international crews and the air, water, food, and equipment they need for extended trips to asteroids, Lagrange Points, and Mars. In addition, the SLS will accommodate high

NASA's Space Launch System: A Flagship for Exploration Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

May, Todd A.

2012-01-01

The National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for exploration beyond Earth orbit in an austere economic climate. This fact drives the SLS team to find innovative solutions to the challenges of designing, developing, fielding, and operating the largest rocket in history. To arrive at the current SLS plan, government and industry experts carefully analyzed hundreds of architecture options and arrived at the one clear solution to stringent requirements for safety, affordability, and sustainability over the decades that the rocket will be in operation. This paper will explore ways to fit this major development within the funding guidelines by using existing engine assets and hardware now in testing to meet a first launch by 2017. It will explain the SLS Program s long-range plan to keep the budget within bounds, yet evolve the 70 metric ton (t) initial lift capability to 130-t lift capability after the first two flights. To achieve the evolved configuration, advanced technologies must offer appropriate return on investment to be selected through a competitive process. For context, the SLS will be larger than the Saturn V that took 12 men on 6 trips for a total of 11 days on the lunar surface over 4 decades ago. Astronauts train for long-duration voyages on the International Space Station, but have not had transportation to go beyond Earth orbit in modern times, until now. NASA is refining its mission manifest, guided by U.S. Space Policy and the Global Exploration Roadmap. Launching the Orion Multi-Purpose Crew Vehicle s (MPCV s) first autonomous certification flight in 2017, followed by a crewed flight in 2021, the SLS will offer a robust way to transport international crews and the air, water, food, and equipment they need for extended trips to asteroids, Lagrange Points, and Mars. In addition, the SLS will accommodate

Mitigating Climate Change with Earth Orbital Sunshades

NASA Technical Reports Server (NTRS)

Coverstone, Victoria; Johnson, Les

2015-01-01

An array of rotating sunshades based on emerging solar sail technology will be deployed in a novel Earth orbit to provide near-continuous partial shading of the Earth, reducing the heat input to the atmosphere by blocking a small percentage of the incoming sunlight, and mitigating local weather effects of anticipated climate change over the next century. The technology will provide local cooling relief during extreme heat events (and heating relief during extreme cold events) thereby saving human lives, agriculture, livestock, water and energy needs. A synthesis of the solar sail design, the sails' operational modes, and the selected orbit combine to provide local weather modification.

An instrument for discrimination between orbital debris and natural particles in near-Earth space

NASA Astrophysics Data System (ADS)

Tuzzolino, A. J.; Simpson, J. A.; McKibben, R. B.; Voss, H. D.; Gursky, H.

1993-08-01

We discuss a SPAce DUSt instrument (SPADUS) under development for flight on the USA ARGOS mission to measure the flux, mass, velocity and trajectory of near-Earth dust. Since natural (cosmic) dust and man-made dust particles (orbital debris) have different velocity and trajectory distributions, they are distinguished by means of the SPADUS velocity/trajectory information. Measurements will cover the dust mass range ~5×10-12 g (2 μm diameter) to ~ 1×10-5g (200 μm diameter), with an expected mean error in particle trajectory of ~7° (isotropic flux).

VIew of Mission Control on first day of ASTP docking in Earth orbit

NASA Image and Video Library

1975-07-15

S75-28483 (15 July 1975) --- An overall view of the Mission Operations Control Room in the Mission Control Center on the first day of the Apollo-Soyuz Test Project docking mission in Earth orbit. The American ASTP flight controllers at NASA's Johnson Space Center were monitoring the progress of the Soviet ASTP launch when this photograph was taken. The television monitor shows cosmonaut Yuri V. Romanenko at his spacecraft communicator?s console in the ASTP mission control center in the Soviet Union. The American ASTP liftoff followed the Soviet ASTP launch by seven and one-half hours.

Acquisition/expulsion system for earth orbital propulsion system study. Volume 2: Cryogenic design

NASA Technical Reports Server (NTRS)

1973-01-01

Detailed designs were made for three earth orbital propulsion systems; (1) the space shuttle (integrated) OMS/RCS, (2) the space shuttle (dedicated) OMS (LO2), and (3) the space tug. The preferred designs from the integrated OMS/RCS were used as the basis for the flight test article design. A plan was prepared that outlines the steps, cost, and schedule required to complete the development of the prototype DSL tank and feedline (LH2 and LO2) systems. Ground testing of a subscale model using LH2 verified the expulsion characteristics of the preferred DSL designs.

Human Mars Mission: Launch Window from Earth Orbit. Pt. 1

NASA Technical Reports Server (NTRS)

Young, Archie

1999-01-01

The determination of orbital window characteristics is of major importance in the analysis of human interplanetary missions and systems. The orbital launch window characteristics are directly involved in the selection of mission trajectories, the development of orbit operational concepts, and the design of orbital launch systems. The orbital launch window problem arises because of the dynamic nature of the relative geometry between outgoing (departure) asymptote of the hyperbolic escape trajectory and the earth parking orbit. The orientation of the escape hyperbola asymptotic relative to the earth is a function of time. The required hyperbola energy level also varies with time. In addition, the inertial orientation of the parking orbit is a function of time because of the perturbations caused by the Earth's oblateness. Thus, a coplanar injection onto the escape hyperbola can be made only at a point in time when the outgoing escape asymptote is contained by the plane of parking orbit. Even though this condition may be planned as a nominal situation, it will not generally represent the more probable injection geometry. The general case of an escape injection maneuver performed at a time other than the coplanar time will involve both a path angle and plane change and, therefore, a delta V penalty. Usually, because of the delta V penalty the actual departure injection window is smaller in duration than that determined by energy requirement alone. This report contains the formulation, characteristics, and test cases for five different launch window modes for Earth orbit. These modes are: 1) One impulsive maneuver from a Highly Elliptical Orbit (HEO); 2) Two impulsive maneuvers from a Highly Elliptical Orbit (HEO); 3) One impulsive maneuver from a Low Earth Orbit (LEO); 4) Two impulsive maneuvers form LEO; and 5) Three impulsive maneuvers form LEO. The formulation of these five different launch window modes provides a rapid means of generating realistic parametric data

On-orbit solar calibrations using the Aqua Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system

NASA Astrophysics Data System (ADS)

Wilson, Robert S.; Priestley, Kory J.; Thomas, Susan; Hess, Phillip

2009-08-01

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometers were used to measure earth-reflected solar and earth-emitted longwave radiances, at satellite altitude. The bolometers measured the earth radiances in the broadband shortwave solar (0.3 - 5.0 micrometers) and total (0.3->100 micrometers) spectral bands as well as in the (8 - 12 micrometers) water vapor window spectral band over geographical footprints as small as 10 kilometers at nadir. In May 2002, the fourth and fifth sets of CERES bolometers were launched aboard the Aqua spacecraft. Ground vacuum calibrations defined the initial count conversion coefficients that were used to convert the bolometer output voltages into filtered earth radiances. The mirror attenuator mosaic (MAM), a solar diffuser plate, was built into the CERES instrument package calibration system in order to define in-orbit shifts or drifts in the sensor responses. The shortwave and total sensors are calibrated using the solar radiances reflected from the MAM's. Each MAM consists of baffle-solar diffuser plate systems, which guide incoming solar radiances into the instrument fields-of-view of the shortwave and total wave sensor units. The MAM diffuser reflecting type surface consists of an array of spherical aluminum mirror segments, which are separated by a Merck Black A absorbing surface, overcoated with silicon dioxide. Temperature sensors are located in each MAM plate and baffle. The CERES MAM wass designed to yield calibration precisions approaching .5 percent for the total and shortwave detectors. In this paper, the MAM solar calibration procedures are presented along with on-orbit results. Comparisons are also made between the Aqua,Terra and the Tropical Rainfall Measurement Mission (TRMM) CERES MAM solar calibrations.

STS-131/19A Flight Control Team in FCR-1 - Orbit 1- Flight Director Ron Spencer

NASA Image and Video Library

2010-04-14

JSC2010-E-052008 (14 April 2010) --- The members of the STS-131/19A ISS Orbit 2 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Ron Spencer (right) holds the STS-131 mission logo.

Orbit Selection for Earth Observation Missions

NASA Technical Reports Server (NTRS)

King, J. C.

1978-01-01

The orbit selection process is simplified for most earth-oriented satellite missions by a restriction to circular orbits, which reduces the primary orbit characteristics to be determined to only two: altitude and inclination. A number of important mission performance characteristics depend on these choices, however, so a major part of the orbit selection task is concerned with developing the correlating relationships in clear and convenient forms to provide a basis for rational orbit selection procedures. The present approach to that task is organized around two major areas of mission performance, orbit plane precession and coverage pattern development, whose dependence on altitude and inclination is delineated graphically in design chart form. These charts provide a visual grasp of the relationships between the quantities cited above, as well as other important mission performance parameters including viewing time of day (solar), sensor swath width (and fields of view), swath sequencing, and pattern repeat condition and repeat periods.

NAVIGATION PERFORMANCE IN HIGH EARTH ORBITS USING NAVIGATOR GPS RECEIVER

NASA Technical Reports Server (NTRS)

Bamford, William; Naasz, Bo; Moreau, Michael C.

2006-01-01

NASA GSFC has developed a GPS receiver that can acquire and track GPS signals with sensitivity significantly lower than conventional GPS receivers. This opens up the possibility of using GPS based navigation for missions in high altitude orbit, such as Geostationary Operational Environmental Satellites (GOES) in a geostationary orbit, and the Magnetospheric MultiScale (MMS) Mission, in highly eccentric orbits extending to 12 Earth radii and higher. Indeed much research has been performed to study the feasibility of using GPS navigation in high Earth orbits and the performance achievable. Recently, GSFC has conducted a series of hardware in-the-loop tests to assess the performance of this new GPS receiver in various high Earth orbits of interest. Tracking GPS signals to down to approximately 22-25 dB-Hz, including signals from the GPS transmitter side-lobes, steady-state navigation performance in a geostationary orbit is on the order of 10 meters. This paper presents the results of these tests, as well as sensitivity analysis to such factors as ionosphere masks, use of GPS side-lobe signals, and GPS receiver sensitivity.

STS-106 Orbit 1 Flight Team with Phil Engelhauf in WFCR

NASA Image and Video Library

2000-09-15

JSC2000-06253 (15 Sept. 2000) --- Flight director Phil Engelauf, front center, and the other fifty-odd flight controllers making up the STS-106 Orbit 1 team, pose for their group portrait in the Flight Control Room of Houston's Mission Control Center.

Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites

NASA Astrophysics Data System (ADS)

Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus

2017-04-01

The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.

Relativity mission with two counter-orbiting polar satellites. [nodal dragging effect on earth orbiting satellites

NASA Technical Reports Server (NTRS)

Van Patten, R. A.; Everitt, C. W. F.

1975-01-01

In 1918, J. Lense and H. Thirring calculated that a moon in orbit around a massive rotating planet would experience a nodal dragging effect due to general relativity. We describe an experiment to measure this effect with two counter-orbiting drag-free satellites in polar earth orbit. For a 2 1/2 year experiment, the measurement accuracy should approach 1%. In addition to precision tracking data from existing ground stations, satellite-to-satellite Doppler ranging data are taken at points of passing near the poles. New geophysical information on both earth harmonics and tidal effects is inherent in the polar ranging data.

Orbit Determination Accuracy for Comets on Earth-Impacting Trajectories

NASA Technical Reports Server (NTRS)

Kay-Bunnell, Linda

2004-01-01

The results presented show the level of orbit determination accuracy obtainable for long-period comets discovered approximately one year before collision with Earth. Preliminary orbits are determined from simulated observations using Gauss' method. Additional measurements are incorporated to improve the solution through the use of a Kalman filter, and include non-gravitational perturbations due to outgassing. Comparisons between observatories in several different circular heliocentric orbits show that observatories in orbits with radii less than 1 AU result in increased orbit determination accuracy for short tracking durations due to increased parallax per unit time. However, an observatory at 1 AU will perform similarly if the tracking duration is increased, and accuracy is significantly improved if additional observatories are positioned at the Sun-Earth Lagrange points L3, L4, or L5. A single observatory at 1 AU capable of both optical and range measurements yields the highest orbit determination accuracy in the shortest amount of time when compared to other systems of observatories.

TROPIX: A solar electric propulsion flight experiment

NASA Technical Reports Server (NTRS)

Hickman, J. Mark; Hillard, G. Barry; Oleson, Steven R.

1993-01-01

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

Evolving the NASA Near Earth Network for the Next Generation of Human Space Flight

NASA Technical Reports Server (NTRS)

Roberts, Christopher J.; Carter, David L.; Hudiburg, John J.; Tye, Robert N.; Celeste, Peter B.

2014-01-01

The purpose of this paper is to present the planned development and evolution of the NASA Near Earth Network (NEN) launch communications services in support of the next generation of human space flight programs. Following the final space shuttle mission in 2011, the two NEN launch communications stations were decommissioned. Today, NASA is developing the next generation of human space flight systems focused on exploration missions beyond low-earth orbit, and supporting the emerging market for commercial crew and cargo human space flight services. The NEN is leading a major initiative to develop a modern high data rate launch communications ground architecture with support from the Kennedy Space Center Ground Systems Development and Operations Program and in partnership with the U.S. Air Force (USAF) Eastern Range. This initiative, the NEN Launch Communications Stations (LCS) development project, successfully completed its System Requirements Review in November 2013. This paper provides an overview of the LCS project and a summary of its progress. The LCS ground architecture, concept of operations, and driving requirements to support the new heavy-lift Space Launch System and Orion Multi-Purpose Crew Vehicle for Exploration Mission-1 are presented. Finally, potential future extensions to the ground architecture beyond EM-1 are discussed.

Observations of Human-Made Debris in Earth Orbit

NASA Technical Reports Server (NTRS)

Cowardia, Heather

2011-01-01

Orbital debris is defined as any human-made object in orbit about the Earth that no longer serves a useful purpose. Beginning in 1957 with the launch of Sputnik 1, there have been more than 4,700 launches, with each launch increasing the potential for impacts from orbital debris. Almost 55 years later there are over 16,000 catalogued objects in orbit over 10 cm in size. Agencies world-wide have realized this is a growing issue for all users of the space environment. To address the orbital debris issue, the Inter-Agency Space Debris Coordination Committee (IADC) was established to collaborate on monitoring, characterizing, and modeling orbital debris, as well as formulating policies and procedures to help control the risk of collisions and population growth. One area of fundamental interest is measurements of the space debris environment. NASA has been utilizing radar and optical measurements to survey the different orbital regimes of space debris for over 25 years, as well as using returned surfaces to aid in determining the flux and size of debris that are too small to detect with ground-based sensors. This paper will concentrate on the optical techniques used by NASA to observe the space debris environment, specifically in the Geosynchronous earth Orbit (GEO) region where radar capability is severely limited.

Safety in earth orbit study. Volume 1: Technical summary

NASA Technical Reports Server (NTRS)

1972-01-01

A summary of the technical results and conclusions is presented of the hazards analyses of earth orbital operations in conjunction with the space shuttle program. The space shuttle orbiter and a variety of manned and unmanned payloads delivered to orbit by the shuttle are considered. The specific safety areas examined are hazardous payloads, docking, on-orbit survivability, tumbling spacecraft, and escape and rescue.

Best Mitigation Paths To Effectively Reduce Earth's Orbital Debris

NASA Technical Reports Server (NTRS)

Wiegman, Bruce M.

2009-01-01

This slide presentation reviews some ways to reduce the problem posed by debris in orbit around the Earth. It reviews the orbital debris environment, the near-term needs to minimize the Kessler syndrome, also known as collisional cascading, a survey of active orbital debris mitigation strategies, the best paths to actively remove orbital debris, and technologies that are required for active debris mitigation.

Orbit Determination of Spacecraft in Earth-Moon L1 and L2 Libration Point Orbits

NASA Technical Reports Server (NTRS)

Woodard, Mark; Cosgrove, Daniel; Morinelli, Patrick; Marchese, Jeff; Owens, Brandon; Folta, David

2011-01-01

The ARTEMIS mission, part of the THEMIS extended mission, is the first to fly spacecraft in the Earth-Moon Lissajous regions. In 2009, two of the five THEMIS spacecraft were redeployed from Earth-centered orbits to arrive in Earth-Moon Lissajous orbits in late 2010. Starting in August 2010, the ARTEMIS P1 spacecraft executed numerous stationkeeping maneuvers, initially maintaining a lunar L2 Lissajous orbit before transitioning into a lunar L1 orbit. The ARTEMIS P2 spacecraft entered a L1 Lissajous orbit in October 2010. In April 2011, both ARTEMIS spacecraft will suspend Lissajous stationkeeping and will be maneuvered into lunar orbits. The success of the ARTEMIS mission has allowed the science team to gather unprecedented magnetospheric measurements in the lunar Lissajous regions. In order to effectively perform lunar Lissajous stationkeeping maneuvers, the ARTEMIS operations team has provided orbit determination solutions with typical accuracies on the order of 0.1 km in position and 0.1 cm/s in velocity. The ARTEMIS team utilizes the Goddard Trajectory Determination System (GTDS), using a batch least squares method, to process range and Doppler tracking measurements from the NASA Deep Space Network (DSN), Berkeley Ground Station (BGS), Merritt Island (MILA) station, and United Space Network (USN). The team has also investigated processing of the same tracking data measurements using the Orbit Determination Tool Kit (ODTK) software, which uses an extended Kalman filter and recursive smoother to estimate the orbit. The orbit determination results from each of these methods will be presented and we will discuss the advantages and disadvantages associated with using each method in the lunar Lissajous regions. Orbit determination accuracy is dependent on both the quality and quantity of tracking measurements, fidelity of the orbit force models, and the estimation techniques used. Prior to Lissajous operations, the team determined the appropriate quantity of tracking

Abort Options for Human Missions to Earth-Moon Halo Orbits

NASA Technical Reports Server (NTRS)

Jesick, Mark C.

2013-01-01

Abort trajectories are optimized for human halo orbit missions about the translunar libration point (L2), with an emphasis on the use of free return trajectories. Optimal transfers from outbound free returns to L2 halo orbits are numerically optimized in the four-body ephemeris model. Circumlunar free returns are used for direct transfers, and cislunar free returns are used in combination with lunar gravity assists to reduce propulsive requirements. Trends in orbit insertion cost and flight time are documented across the southern L2 halo family as a function of halo orbit position and free return flight time. It is determined that the maximum amplitude southern halo incurs the lowest orbit insertion cost for direct transfers but the maximum cost for lunar gravity assist transfers. The minimum amplitude halo is the most expensive destination for direct transfers but the least expensive for lunar gravity assist transfers. The on-orbit abort costs for three halos are computed as a function of abort time and return time. Finally, an architecture analysis is performed to determine launch and on-orbit vehicle requirements for halo orbit missions.

Prevalence of Earth-size planets orbiting Sun-like stars.

PubMed

Petigura, Erik A; Howard, Andrew W; Marcy, Geoffrey W

2013-11-26

Determining whether Earth-like planets are common or rare looms as a touchstone in the question of life in the universe. We searched for Earth-size planets that cross in front of their host stars by examining the brightness measurements of 42,000 stars from National Aeronautics and Space Administration's Kepler mission. We found 603 planets, including 10 that are Earth size ( ) and receive comparable levels of stellar energy to that of Earth (1 - 2 R[Symbol: see text] ). We account for Kepler's imperfect detectability of such planets by injecting synthetic planet-caused dimmings into the Kepler brightness measurements and recording the fraction detected. We find that 11 ± 4% of Sun-like stars harbor an Earth-size planet receiving between one and four times the stellar intensity as Earth. We also find that the occurrence of Earth-size planets is constant with increasing orbital period (P), within equal intervals of logP up to ~200 d. Extrapolating, one finds 5.7(-2.2)(+1.7)% of Sun-like stars harbor an Earth-size planet with orbital periods of 200-400 d.

Prevalence of Earth-size planets orbiting Sun-like stars

PubMed Central

Petigura, Erik A.; Howard, Andrew W.; Marcy, Geoffrey W.

2013-01-01

Determining whether Earth-like planets are common or rare looms as a touchstone in the question of life in the universe. We searched for Earth-size planets that cross in front of their host stars by examining the brightness measurements of 42,000 stars from National Aeronautics and Space Administration’s Kepler mission. We found 603 planets, including 10 that are Earth size () and receive comparable levels of stellar energy to that of Earth (). We account for Kepler’s imperfect detectability of such planets by injecting synthetic planet–caused dimmings into the Kepler brightness measurements and recording the fraction detected. We find that 11 ± 4% of Sun-like stars harbor an Earth-size planet receiving between one and four times the stellar intensity as Earth. We also find that the occurrence of Earth-size planets is constant with increasing orbital period (P), within equal intervals of logP up to ∼200 d. Extrapolating, one finds % of Sun-like stars harbor an Earth-size planet with orbital periods of 200–400 d. PMID:24191033

Wind Tunnel Measurements of Shuttle Orbiter Global Heating with Comparisons to Flight

NASA Technical Reports Server (NTRS)

Berry, Scott A.; Merski, N. Ronald; Blanchard, Robert C.

2002-01-01

An aerothermodynamic database of global heating images was acquired of the Shuttle Orbiter in the NASA Langley Research Center 20-Inch Mach 6 Air Tunnel. These results were obtained for comparison to the global infrared images of the Orbiter in flight from the infrared sensing aeroheating flight experiment (ISAFE). The most recent ISAFE results from STS-103, consisted of port side images, at hypersonic conditions, of the surface features that result from the strake vortex scrubbing along the side of the vehicle. The wind tunnel results were obtained with the phosphor thermography system, which also provides global information and thus is ideally suited for comparison to the global flight results. The aerothermodynamic database includes both windward and port side heating images of the Orbiter for a range of angles of attack (20 to 40 deg), freestream unit Reynolds number (1 x 10(exp 6))/ft to 8 x 10(exp 6)/ft, body flap deflections (0, 5, and 10 deg), speed brake deflections (0 and 45 deg), as well as with boundary layer trips for forced transition to turbulence heating results. Sample global wind tunnel heat transfer images were extrapolated to flight conditions for comparison to Orbiter flight data. A windward laminar case for an angle of attack of 40 deg was extrapolated to Mach 11.6 flight conditions for comparison to STS-2 flight thermocouple results. A portside wind tunnel image for an angle of attack of 25 deg was extrapolated for Mach 5 flight conditions for comparison to STS-103 global surface temperatures. The comparisons showed excellent qualitative agreement, however the extrapolated wind tunnel results over-predicted the flight surface temperatures on the order of 5% on the windward surface and slightly higher on the portside.

NASA Computational Case Study: The Flight of Friendship 7

NASA Technical Reports Server (NTRS)

Simpson, David G.

2012-01-01

In this case study, we learn how to compute the position of an Earth-orbiting spacecraft as a function of time. As an exercise, we compute the position of John Glenn's Mercury spacecraft Friendship 7 as it orbited the Earth during the third flight of NASA's Mercury program.

Collisional cascading - The limits of population growth in low earth orbit

NASA Technical Reports Server (NTRS)

Kessler, Donald J.

1991-01-01

Random collisions between made-made objects in earth orbit will lead to a significant source of orbital debris, but there are a number of uncertainties in these models, and additional analysis and data are required to fully characterize the future environment. However, the nature of these uncertainties are such that while the future environment is uncertain, the fact that collisions will control the future environment is less uncertain. The data that already exist is sufficient to show that cascading collisions will control the future debris environment with no, or very minor increases in the current low-earth-orbit population. Two populations control this process: explosion fragments and expended rocket bodies and payloads. Practices are already changing to limit explosions in low earth orbit; it is necessary to begin limiting the number of expended rocket bodies and payloads in orbit.

Moonport: Transportation node in lunar orbit

NASA Technical Reports Server (NTRS)

1987-01-01

An orbital transporation system between the Earth and Moon was designed. The design work focused on the requirements and configuration of an orbiting lunar base. The design utilized current Space Station technologies, but also focused on the specific requirements involved with a permanently manned, orbiting lunar station. A model of the recommended configuration was constructed. In order to analyze Moonport activity and requirements, a traffic model was designed, defining traffic between the lunar port, or Moonport and low Earth orbit. Also, a lunar base model was used to estimate requirements of the surface base on Moonport traffic and operations. A study was conducted to compare Moonport traffic and operations based in low lunar orbit and the L (sub 2) equilibrium point, behind the Moon. The study compared delta-V requirements to each location and possible payload deliveries to low Earth orbit from each location. Products of the Moonport location study included number of flights annually to Moonport, net payload delivery to low Earth orbit, and Moonport storage requirement.

Need for expanded environmental measurement capabilities in geosynchronous Earth orbit

NASA Technical Reports Server (NTRS)

Mercanti, Enrico P.

1991-01-01

The proliferation of environmental satellites in low altitude earth orbit (LEO) has demonstrated the usefulness of earth remote sensing from space. As use of the technology grows, the limitations of LEO missions become more apparent. Many inadequacies can be met by remote sensing from geosynchronous earth orbits (GEO) that can provide high temporal resolution, consistent viewing of specific earth targets, long sensing dwell times with varying sun angles, stereoscopic coverage, and correlative measurements with ground and LEO observations. An environmental platform in GEO is being studied by NASA. Small research satellite missions in GEO were studied (1990) at GSFC. Some recent independent assessments of NASA Earth Science Programs recommend accelerating the earlier deployment of smaller missions.

STS-70 Post Flight Presentation

NASA Technical Reports Server (NTRS)

Peterson, Glen (Editor)

1995-01-01

In this post-flight overview, the flight crew of the STS-70 mission, Tom Henricks (Cmdr.), Kevin Kregel (Pilot), Major Nancy Currie (MS), Dr. Mary Ellen Weber (MS), and Dr. Don Thomas (MS), discuss their mission and accompanying experiments. Pre-flight, launch, and orbital footage is followed by the in-orbit deployment of the Tracking and Data Relay Satellite (TDRS) and a discussion of the following spaceborne experiments: a microgravity bioreactor experiment to grow 3D body-like tissue; pregnant rat muscular changes in microgravity; embryonic development in microgravity; Shuttle Amateur Radio Experiment (SAREX); terrain surface imagery using the HERCULES camera; and a range of other physiological tests, including an eye and vision test. Views of Earth include: tropical storm Chantal; the Nile River and Red Sea; lightning over Brazil. A three planet view (Earth, Mars, and Venus) was taken right before sunrise. The end footage shows shuttle pre-landing checkout, entry, and landing, along with a slide presentation of the flight.

Earth view: A business guide to orbital remote sensing

NASA Technical Reports Server (NTRS)

Bishop, Peter C.

1990-01-01

The following subject areas are covered: Earth view - a guide to orbital remote sensing; current orbital remote sensing systems (LANDSAT, SPOT image, MOS-1, Soviet remote sensing systems); remote sensing satellite; and remote sensing organizations.

Space Shuttle Orbiter thermal protection system design and flight experience

NASA Technical Reports Server (NTRS)

Curry, Donald M.

1993-01-01

The Space Shuttle Orbiter Thermal Protection System materials, design approaches associated with each material, and the operational performance experienced during fifty-five successful flights are described. The flights to date indicate that the thermal and structural design requirements were met and that the overall performance was outstanding.

Integrated digital flight-control system for the space shuttle orbiter

NASA Technical Reports Server (NTRS)

1973-01-01

The integrated digital flight control system is presented which provides rotational and translational control of the space shuttle orbiter in all phases of flight: from launch ascent through orbit to entry and touchdown, and during powered horizontal flights. The program provides a versatile control system structure while maintaining uniform communications with other programs, sensors, and control effectors by using an executive routine/functional subroutine format. The program reads all external variables at a single point, copies them into its dedicated storage, and then calls the required subroutines in the proper sequence. As a result, the flight control program is largely independent of other programs in the GN&C computer complex and is equally insensitive to the characteristics of the processor configuration. The integrated structure of the control system and the DFCS executive routine which embodies that structure are described along with the input and output. The specific estimation and control algorithms used in the various mission phases are given.

STS-131/19A Flight Control Team in FCR-1 - Orbit 1- Flight Director Courtney McMillan

NASA Image and Video Library

2010-04-14

JSC2010-E-052979 (14 April 2010) --- The members of the STS-131/19A ISS Orbit 1 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Courtenay McMillan (center) stands on the front row.

STS-131/19A Flight Control Team in FCR-1 - Orbit 3- Flight Director Ed Van Cise

NASA Image and Video Library

2010-04-14

JSC2010-E-052556 (14 April 2010) --- The members of the STS-131/19A ISS Orbit 3 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Ed Van Cise holds the STS-131 mission logo.

Optical property degradation of anodic coatings in the Space Station low earth orbit

NASA Technical Reports Server (NTRS)

David, Kaia E.; Babel, Hank W.

1992-01-01

The anodic coatings and optical properties to be used for passive thermal control of the SSF are studied. Particular attention is given to the beginning-of-life optical properties for aluminum alloys suitable for structural and radiator applications, the statistical variation in the beginning-of-life properties, and estimates of the end-of-life properties of the alloys based on ultraviolet radiation testing and flight test results. It is concluded that anodic coatings can be used for thermal control of long life, low earth orbit spacecraft. Some use restrictions are defined for specific cases. Anodic coatings have been selected as baseline thermal control coating for large portions of the SSF.

STS-124/1J ISS Orbit 3 flight control team portrait

NASA Image and Video Library

2008-06-09

JSC2008-E-045777 (9 June 2008) --- The members of the STS-124/1J ISS Orbit 3 flight control team pose for a group portrait in the space station flight control room in the Mission Control Center at NASA's Johnson Space Center. Flight director Emily Nelson stands in the center foreground.

STS-107 Flight Day 7 Highlights

NASA Technical Reports Server (NTRS)

2003-01-01

This video shows the activities of the STS-107 crew (Rick Husband, Commander; William McCool, Pilot; Kalpana Chawla, David Brown, Michael Anderson, Laurel Clark, Mission Specialists; Ilan Ramon, Payload Specialist) during flight day 7 of the Columbia orbiter's final flight. The primary activities of flight day 7 are setting up and conducting spaceborne experiments in the SpaceHab RDM (Research Double Module) in the orbiter's payload bay. Silkworms and ants from the STARS (Space Technology and Research Students) international student experiments are shown. Footage of the Mediterranean Sea taken by the MEIDEX (Mediterranean Israeli Dust Experiment) is also shown. Canisters containing experiments attached to the SpaceHab RDM are shown in the space shuttle's payload bay. Other views include the Earth's surface, and the Earth's atmosphere, visible along its limb.

General view of the flight deck of the orbiter Discovery ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

General view of the flight deck of the orbiter Discovery looking forward and overhead at the overhead instrumentation and control panels. This view was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

Proving the Space Transportation System: the Orbital Flight Test Program

NASA Technical Reports Server (NTRS)

Reichhardt, T.

1982-01-01

The main propulsion system, solid rocket boosters, external tank, orbital maneuvering system, spacecraft orbital operations (thermal tests, attitude control and remote manipulator), and return to Earth are outlined for the first four STS missions.

Methods for extracting aerodynamic accelerations from Orbiter High Resolution Accelerometer Package flight data

NASA Technical Reports Server (NTRS)

Thompson, J. M.; Russell, J. W.; Blanchard, R. C.

1987-01-01

This report presents a process for extracting the aerodynamic accelerations of the Shuttle Orbiter Vehicle from the High Resolution Accelerometer Package (HiRAP) flight data during reentry. The methods for obtaining low-level aerodynamic accelerations, principally in the rarefied flow regime, are applied to 10 Orbiter flights. The extraction process is presented using data obtained from Space Transportation System Flight 32 (Mission 61-C) as a typical example. This process involves correcting the HiRAP measurements for the effects of temperature bias and instrument offset from the Orbiter center of gravity, and removing acceleration data during times they are affected by thruster firings. The corrected data are then made continuous and smooth and are further enhanced by refining the temperature bias correction and removing effects of the auxiliary power unit actuation. The resulting data are the current best estimate of the Orbiter aerodynamic accelerations during reentry and will be used for further analyses of the Orbiter aerodynamics and the upper atmosphere characteristics.

Nickel hydrogen low Earth orbit life testing

NASA Technical Reports Server (NTRS)

Badcock, C. C.; Haag, R. L.

1986-01-01

A program to demonstrate the long term reliability of NiH2 cells in low Earth orbits (LEO) and support use in mid-altitude orbits (MAO) was initiated. Both 3.5 and 4.5 inch diameter nickel hydrogen cells are included in the test plan. Cells from all U.S. vendors are to be tested. The tests will be performed at -5 and 10 C at 40 and 60% DOD for LEO orbit and 10 C and 80% DOD for MAO orbit simulations. The goals of the testing are 20,000 cycles at 60% DOD and 30,000 cycles at 40% DOD. Cells are presently undergoing acceptance and characterization testing at Naval Weapons Systems Center, Crane.

Low Earth Orbital Atomic Oxygen Interactions With Spacecraft Materials

NASA Technical Reports Server (NTRS)

Banks, Bruce A.; deGroh, Kim K.; Miller, Sharon K.

2004-01-01

Atomic oxygen, formed in Earth s thermosphere, interacts readily with many materials on spacecraft flying in low Earth orbit (LEO). All hydrocarbon based polymers and graphite are easily oxidized upon the impact of approx.4.5 eV atomic oxygen as the spacecraft ram into the residual atmosphere. The resulting interactions can change the morphology and reduce the thickness of these materials. Directed atomic oxygen erosion will result in the development of textured surfaces on all materials with volatile oxidation products. Examples from space flight samples are provided. As a result of the erosive properties of atomic oxygen on polymers and composites, protective coatings have been developed and are used to increase the functional life of polymer films and composites that are exposed to the LEO environment. The atomic oxygen erosion yields for actual and predicted LEO exposure of numerous materials are presented. Results of in-space exposure of vacuum deposited aluminum protective coatings on polyimide Kapton indicate high rates of degradation are associated with aluminum coatings on both surfaces of the Kapton. Computational modeling predictions indicate that less trapping of the atomic oxygen occurs, with less resulting damage, if only the space-exposed surface is coated with vapor deposited aluminum rather than having both surfaces coated.

ULA's Atlas V for Boeing's Orbital Flight Test

NASA Image and Video Library

2017-10-24

The Atlas V rocket that will launch Boeing’s CST-100 Starliner spacecraft on the company’s uncrewed Orbital Flight Test for NASA’s Commercial Crew Program is coming together inside a United Launch Alliance facility in Decatur, Alabama. The flight test is intended to prove the design of the integrated space system prior to the Crew Flight Test. These events are part of NASA’s required certification process as the company works to regularly fly astronauts to and from the International Space Station. Boeing's Starliner will launch on the United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida.

Advanced Earth-to-orbit propulsion technology information, dissemination and research

NASA Technical Reports Server (NTRS)

Wu, S. T.

1995-01-01

In this period of performance a conference (The 1994 Conference on Advanced Earth-to-Orbit Propulsion Technology) was organized and implemented by the University of Alabama in Huntsville and held May 15-17 to assemble and disseminate the current information on Advanced Earth-to-Orbit Propulsion Technology. The results were assembled for publication as NASA-CP-3282, Volume 1 and 2 and NASA-CP-3287.

Comparison of TOPEX/Poseidon orbit determination solutions obtained by the Goddard Space Flight Center Flight Dynamics Division and Precision Orbit Determination Teams

NASA Technical Reports Server (NTRS)

Doll, C.; Mistretta, G.; Hart, R.; Oza, D.; Cox, C.; Nemesure, M.; Bolvin, D.; Samii, Mina V.

1993-01-01

Orbit determination results are obtained by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) using the Goddard Trajectory Determination System (GTDS) and a real-time extended Kalman filter estimation system to process Tracking Data and Relay Satellite (TDRS) System (TDRSS) measurements in support of the Ocean Topography Experiment (TOPEX)/Poseidon spacecraft navigation and health and safety operations. GTDS is the operational orbit determination system used by the FDD, and the extended Kalman fliter was implemented in an analysis prototype system, the Real-Time Orbit Determination System/Enhanced (RTOD/E). The Precision Orbit Determination (POD) team within the GSFC Space Geodesy Branch generates an independent set of high-accuracy trajectories to support the TOPEX/Poseidon scientific data. These latter solutions use the Geodynamics (GEODYN) orbit determination system with laser ranging tracking data. The TOPEX/Poseidon trajectories were estimated for the October 22 - November 1, 1992, timeframe, for which the latest preliminary POD results were available. Independent assessments were made of the consistencies of solutions produced by the batch and sequential methods. The batch cases were assessed using overlap comparisons, while the sequential cases were assessed with covariances and the first measurement residuals. The batch least-squares and forward-filtered RTOD/E orbit solutions were compared with the definitive POD orbit solutions. The solution differences were generally less than 10 meters (m) for the batch least squares and less than 18 m for the sequential estimation solutions. The differences among the POD, GTDS, and RTOD/E solutions can be traced to differences in modeling and tracking data types, which are being analyzed in detail.

Space shuttle orbiter leading-edge flight performance compared to design goals

NASA Technical Reports Server (NTRS)

Curry, D. M.; Johnson, D. W.; Kelly, R. E.

1983-01-01

Thermo-structural performance of the Space Shuttle orbiter Columbia's leading-edge structural subsystem for the first five (5) flights is compared with the design goals. Lessons learned from thse initial flights of the first reusable manned spacecraft are discussed in order to assess design maturity, deficiencies, and modifications required to rectify the design deficiencies. Flight data and post-flight inspections support the conclusion that the leading-edge structural subsystem hardware performance was outstanding for the initial five (5) flights.

Apollo-Lunar Orbital Rendezvous Technique

NASA Technical Reports Server (NTRS)

1963-01-01

The film shows artists rendition of the spacecrafts, boosters, and flight of the Apollo lunar missions. The Apollo spacecraft will consist of three modules: the manned Command Module; the Service Module, which contains propulsion systems; and the Lunar Excursion Module (LEM) to carry astronauts to the moon and back to the Command and Service Modules. The spacecraft will be launched via a three-stage Saturn booster. The first stage will provide 7.5 million pounds of thrust from five F-1 engines for liftoff and initial powered flight. The second stage will develop 1 million pounds of thrust from five J-2 engines to boost the spacecraft almost into Earth orbit. Immediately after ignition of the second stage, the Launch Escape System will be jettisoned. A single J-2 engine in the S4B stage will provide 200,000 pounds of thrust to place the spacecraft in an earth parking orbit. It also will be used to propel the spacecraft into a translunar trajectory, then it will separate from the Apollo Modules. Onboard propulsion systems will be used to insert the spacecraft into lunar orbit. Two astronauts will enter the LEM, which will separate from the command and service modules. The LEM will go into elliptical orbit and prepare for landing. The LEM will lift off of the Moon's surface to return to the Command and Service Modules, and most likely be left in lunar orbit. After leaving the Moon's orbit, and shortly before entering Earth's orbit, the Service Module will be ejected. The Command Module will be oriented for reentry into the Earth's atmosphere. A drogue parachute will deploy at approximately 50,000 feet, followed by the main parachute system for touchdown.

Access to Mars from Earth-Moon Libration Point Orbits:. [Manifold and Direct Options

NASA Technical Reports Server (NTRS)

Kakoi, Masaki; Howell, Kathleen C.; Folta, David

2014-01-01

This investigation is focused specifically on transfers from Earth-Moon L(sub 1)/L(sub 2) libration point orbits to Mars. Initially, the analysis is based in the circular restricted three-body problem to utilize the framework of the invariant manifolds. Various departure scenarios are compared, including arcs that leverage manifolds associated with the Sun-Earth L(sub 2) orbits as well as non-manifold trajectories. For the manifold options, ballistic transfers from Earth-Moon L(sub 2) libration point orbits to Sun-Earth L(sub 1)/L(sub 2) halo orbits are first computed. This autonomous procedure applies to both departure and arrival between the Earth-Moon and Sun-Earth systems. Departure times in the lunar cycle, amplitudes and types of libration point orbits, manifold selection, and the orientation/location of the surface of section all contribute to produce a variety of options. As the destination planet, the ephemeris position for Mars is employed throughout the analysis. The complete transfer is transitioned to the ephemeris model after the initial design phase. Results for multiple departure/arrival scenarios are compared.

History of Manned Space Flight

NASA Technical Reports Server (NTRS)

1975-01-01

U.S. manned space projects from Mercury Redstone 3 through Skylab 4 are briefly described including dates, flight duration, crew, and number of earth/moon orbits. The flight costs of each project are itemized. Highlights in the history of the manned space program from 1957 to February, 1974 are included.

STS-113 Flight Control Team Photo in WFCR - Orbit 2 with Flight Director John Curry.

NASA Image and Video Library

2002-11-27

JSC2002-02106 (27 November 2002) --- The members of the STS-113 Orbit 2 Team pose for a group portrait in the shuttle flight control room (WFCR) in Houston’s Mission Control Center (MCC). Flight Director John Curry stands to the left of the STS-113 mission logo and astronaut Lisa M. Nowak, spacecraft communicator (CAPCOM), stands to the left of Curry.

Perturbed Equations of Motion for Formation Flight Near the Sun-Earth L2 Point

NASA Technical Reports Server (NTRS)

Segerman, Alan M.; Zedd, Michael F.

2005-01-01

This Memorandum Report consists of a compilation of three individual reports, of increasing complexity, describing investigations of formation flight of spacecraft in the vicinity of the L2 Sun-Earth 1ibration point. The individual reports form the following parts of this compilation: - Introduction to the relative motion of spacecraft about the Sun-Earth L2 Point - Linear and quadratic modelling and solution of the relative motion - Modelling the Perturbations - Elliptical Earth Orbit, Lunar Gravity, Solar Radiation Pressure, Thrusters. The three parts are self-contained, with somewhat, varying notation and terminology. After fair1y significant literature searches: this new work (of Parts 2 and 3) is deemed to be unique because it describes the primary perturbations to the description of relative motion between nearby spacecraft. The effect of the elliptical motion of the Earth about the Sun was verified to be the dominant perturbation to the circular restricted three body problem. Contributions due to lunar gravity and solar radiation pressure are seen to have much smaller effect.

Smartphone Photos From Orbit

NASA Image and Video Library

2017-12-08

These images of Earth were reconstructed from photos taken by three smartphones in orbit, or "PhoneSats." The trio of PhoneSats launched on April 21, 2013, aboard the Antares rocket from NASA's Wallops Flight Facility and ended a successful mission on April 27. The ultimate goal of the PhoneSat mission was to determine whether a consumer-grade smartphone can be used as the main flight avionics for a satellite in space. During their time in orbit, the three miniature satellites used their smartphone cameras to take pictures of Earth and transmitted these "image-data packets" to multiple ground stations. Every packet held a small piece of the big picture. As the data became available, the PhoneSat Team and multiple amateur radio operators around the world collaborated to piece together photographs from the tiny data packets. Read more: 1.usa.gov/ZsWnQG Credit: NASA/Ames NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Servicing and Deployment of National Resources in Sun-Earth Libration Point Orbits

NASA Technical Reports Server (NTRS)

Folta, David C.; Beckman, Mark; Mar, Greg C.; Mesarch, Michael; Cooley, Steven; Leete, Steven J.

2002-01-01

Spacecraft travel between the Sun-Earth system, the Earth-Moon system, and beyond has received extensive attention recently. The existence of a connection between unstable regions enables mission designers to envision scenarios of multiple spacecraft traveling cheaply from system to system, rendezvousing, servicing, and refueling along the way. This paper presents examples of transfers between the Sun-Earth and Earth-Moon systems using a true ephemeris and perturbation model. It shows the (Delta)V costs associated with these transfers, including the costs to reach the staging region from the Earth. It explores both impulsive and low thrust transfer trajectories. Additionally, analysis that looks specifically at the use of nuclear power in libration point orbits and the issues associated with them such as inadvertent Earth return is addressed. Statistical analysis of Earth returns and the design of biased orbits to prevent any possible return are discussed. Lastly, the idea of rendezvous between spacecraft in libration point orbits using impulsive maneuvers is addressed.

Dynamical sequestration of the Moon-forming impactor in co-orbital resonance with Earth

NASA Astrophysics Data System (ADS)

Kortenkamp, Stephen J.; Hartmann, William K.

2016-09-01

Recent concerns about the giant impact hypothesis for the origin of the Moon, and an associated "isotope crisis" may be assuaged if the impactor was a local object that formed near Earth. We investigated a scenario that may meet this criterion, with protoplanets assumed to originate in 1:1 co-orbital resonance with Earth. Using N-body numerical simulations we explored the dynamical consequences of placing Mars-mass companions in various co-orbital configurations with a proto-Earth of 0.9 Earth-masses (M⊕). We modeled 162 different configurations, some with just the four terrestrial planets and others that included the four giant planets. In both the 4- and 8-planet models we found that a single Mars-mass companion typically remained a stable co-orbital of Earth for the entire 250 million year (Myr) duration of our simulations (59 of 68 unique simulations). In an effort to destabilize such a system we carried out an additional 94 simulations that included a second Mars-mass co-orbital companion. Even with two Mars-mass companions sharing Earth's orbit about two-thirds of these models (66) also remained stable for the entire 250 Myr duration of the simulations. Of the 28 2-companion models that eventually became unstable 24 impacts were observed between Earth and an escaping co-orbital companion. The average delay we observed for an impact of a Mars-mass companion with Earth was 102 Myr, and the longest delay was 221 Myr. In 40% of the 8-planet models that became unstable (10 out of 25) Earth collided with the nearly equal mass Venus to form a super-Earth (loosely defined here as mass ≥1.7 M⊕). These impacts were typically the final giant impact in the system and often occurred after Earth and/or Venus has accreted one or more of the other large objects. Several of the stable configurations involved unusual 3-planet hierarchical co-orbital systems.

Orbiter Enterprise at Marshall Space Flight Center for testing

NASA Image and Video Library

2002-10-29

In this view, the Shuttle Orbiter Enterprise is seen heading South on Rideout Road with Marshall Space Flight Center's (MSFC'S) administrative 4200 Complex in the background, as it is being transported to MSFC's building 4755 for later Mated Vertical Ground Vibration tests (MVGVT) at MSFC's Dynamic Test Stand. The tests marked the first time ever that the entire shuttle complement (including Orbiter, external tank, and solid rocket boosters) were mated vertically.

Earth observation mission operation of COMS during in-orbit test

NASA Astrophysics Data System (ADS)

Cho, Young-Min

2011-11-01

Communication Ocean Meteorological Satellite (COMS) for the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service was launched onto Geostationary Earth Orbit on June 27, 2010 and it is currently under normal operation service after the In-Orbit Test (IOT) phase. The COMS is located on 128.2° East of the geostationary orbit. In order to perform the three missions, the COMS has 3 separate payloads, the meteorological imager (MI), the Geostationary Ocean Color Imager (GOCI), and the Ka-band antenna. Each payload is dedicated to one of the three missions, respectively. The MI and GOCI perform the Earth observation mission of meteorological observation and ocean monitoring, respectively. During the IOT phase the functionality and the performance of many aspects of the COMS satellite and ground station have been checked through the Earth observation mission operation for the observation of the meteorological phenomenon over several areas of the Earth and the monitoring of marine environments around the Korean peninsula. The Earth observation mission operation of COMS during the IOT phase is introduced in terms of mission operation characteristics, mission planning, and mission operation results for the missions of meteorological observation and ocean monitoring, respectively.

ISS-12A.1 Orbit 1 Flight Control Team in FCR-1 with Flight Director Derek Hassmann

NASA Image and Video Library

2006-12-15

JSC2006-E-54411 (15 Dec. 2006) --- The members of the STS-116/12A.1 ISS Orbit 1 flight control team pose for a group portrait in the station flight control room of Houston's Mission Control Center (MCC). Flight director Derek Hassman (center right) holds the STS-116 mission logo. Astronaut Terry W. Virts Jr., spacecraft communicator (CAPCOM), is at center. PHALCON flight controller Scott Stover (center left) holds the P5 truss power reconfiguration logo.

Electric Propulsion for Low Earth Orbit Constellations

NASA Technical Reports Server (NTRS)

Oleson, Steven R.; Sankovic, John M.

1998-01-01

Hall Effect electric propulsion was evaluated for orbit insertion, satellite repositioning, orbit maintenance and de-orbit applications for a sample low earth orbit satellite constellation. Since the low masses of these satellites enable multiple spacecraft per launch, the ability to add spacecraft to a given launch was used as a figure of merit. When compared to chemical propulsion, the Hall thruster system can add additional spacecraft per launch using planned payload power levels. One satellite can be added to the assumed four satellite baseline chemical launch without additional mission times. Two or three satellites may be added by providing part of the orbit insertion with the Hall system. In these cases orbit insertion times were found to be 35 and 62 days. Depending on the electric propulsion scenario, the resulting launch vehicle savings is nearly two, three or four Delta 7920 launch vehicles out of the chemical baseline scenarios eight Delta 7920 launch vehicles.

Electric Propulsion for Low Earth Orbit Constellations

NASA Technical Reports Server (NTRS)

Oleson, Steven R.; Sankovic, John M.

1998-01-01

Hall effect electric propulsion was evaluated for orbit insertion, satellite repositioning, orbit maintenance and de-orbit applications for a sample low earth orbit satellite constellation. Since the low masses of these satellites enable multiple spacecraft per launch, the ability to add spacecraft to a given launch was used as a figure of merit. When compared to chemical propulsion, the Hall thruster system can add additional spacecraft per launch using planned payload power levels. One satellite can be added to the assumed four satellite baseline chemical launch without additional mission times. Two or three satellites may be added by providing part of the orbit insertion with the Hall system. In these cases orbit insertion times were found to be 35 and 62 days. Depending, on the electric propulsion scenario, the resulting launch vehicle savings is nearly two, three or four Delta 7920 launch vehicles out of the chemical baseline scenario's eight Delta 7920 launch vehicles.

STS-125 Flight Control Team in BFCR - HST Orbit & Planning Teams

NASA Image and Video Library

2009-05-18

JSC2009-E-120479 (18 May 2009) --- Members of the STS-125 Hubble Space Telescope Planning and Orbit flight control team pose for a group portrait in the blue flight control room in the Mission Control Center at NASA's Johnson Space Center.

STS-125 Flight Control Team in BFCR - HST Planning & Orbit Team

NASA Image and Video Library

2009-05-19

JSC2009-E-120701 (19 May 2009) --- Members of the STS-125 Hubble Space Telescope Planning and Orbit flight control team pose for a group portrait in the blue flight control room in the Mission Control Center at NASA's Johnson Space Center.

Thermal and orbital analysis of Earth monitoring Sun-synchronous space experiments

NASA Technical Reports Server (NTRS)

Killough, Brian D.

1990-01-01

The fundamentals of an Earth monitoring Sun-synchronous orbit are presented. A Sun-synchronous Orbit Analysis Program (SOAP) was developed to calculate orbital parameters for an entire year. The output from this program provides the required input data for the TRASYS thermal radiation computer code, which in turn computes the infrared, solar and Earth albedo heat fluxes incident on a space experiment. Direct incident heat fluxes can be used as input to a generalized thermal analyzer program to size radiators and predict instrument operating temperatures. The SOAP computer code and its application to the thermal analysis methodology presented, should prove useful to the thermal engineer during the design phases of Earth monitoring Sun-synchronous space experiments.

SSC Tenant Meeting: NASA Near Earth Network (NEN) Overview

NASA Technical Reports Server (NTRS)

Carter, David; Larsen, David; Baldwin, Philip; Wilson, Cristy; Ruley, LaMont

2018-01-01

The Near Earth Network (NEN) consists of globally distributed tracking stations that are strategically located throughout the world which provide Telemetry, Tracking, and Commanding (TTC) services support to a variety of orbital and suborbital flight missions, including Low Earth Orbit (LEO), Geosynchronous Earth Orbit (GEO), highly elliptical, and lunar orbits. Swedish Space Corporation (SSC), which is one of the NEN Commercial Service Provider, has provided the NEN with TTC services support from its Alaska, Hawaii, Chile and Sweden. The presentation will give an overview of the NEN and its support from SSC.

Low Earth Orbit (LEO) Commercial Market Projections

DOT National Transportation Integrated Search

1995-05-16

This study assesses the possible number of small commercial satellites to be : launched to Low Earth Orbit (LEO) in the period 1995-2005. The information : provided reflects an Office of Commercial Space Transportation (OCST) : assessment of overall ...

Degradation mechanisms of materials for large space systems in low Earth orbit

NASA Technical Reports Server (NTRS)

Gordon, William L.; Hoffman, R. W.

1987-01-01

Degradation was explored of various materials used in aerospace vehicles after severe loss of polymeric material coatings (Kapton) was observed on an early shuttle flight in low Earth orbit. Since atomic oxygen is the major component of the atmosphere at 300 km, and the shuttle's orbital velocity produced relative motion corresponding to approx. 5 eV of oxygen energy, it was natural to attribute much of this degradation to oxygen interaction. This assumption was tested using large volume vacuum systems and ion beam sources, in an exploratory effort to produce atomic oxygen of the appropriate energy, and to observe mass loss from various samples as well as optical radiation. Several investigations were initiated and the results of these investigations are presented in four papers. These papers are summarized. They are entitled: (1) The Space Shuttle Glow; (2) Laboratory Degradation of Kapton in a Low Energy Oxygen Ion Beam; (3) The Energy Dependence and Surface Morphology of Kapton Degradation Under Atomic Oxygen Bombardment; and (4) Surface Analysis of STS 8 Samples.

Rat gestation during space flight: outcomes for dams and their offspring born after return to Earth.

PubMed

Wong, A M; DeSantis, M

1997-01-01

Sprague-Dawley rats were studied to learn whether gestation in the near-zero gravity, high radiation environment of space impacts selected mammalian postnatal events. Ten rats spent days nine to twenty of pregnancy aboard the space shuttle orbiter Atlantis (STS-66). Their movement was studied shortly after return to Earth; subsequently, several of their offspring were cross-fostered and examined through postnatal day 81 (P81) for whole body growth and somatic motor development. Values for the flight animals were compared to ground-based control groups. Relative to controls, the pregnant flight rats showed a marked paucity of locomotion during the first few hours after returning to Earth. There was greater likelihood of perinatal morbidity for the offspring of flight dams when compared to the control groups. Whole body weight of surviving offspring, averaged for each group separately, showed typical sigmoidal growth curves when plotted against postnatal age. The flight group for our study had a larger ratio of female to male pups, and that was sufficient to account for the lower average daily weight gained by the flight animals when compared to the control groups. Walking was universally achieved by P13 and preceded eye opening, which was complete in all pups by P17. Thus, both of these developmental horizons were attained on schedule in the flight as well as the control rats. Characteristic changes were observed in hind limb step length and gait width as the pups grew. These patterns occurred at the same time in each group of rats. Therefore, prenatal space flight from days nine to twenty of gestation did not interfere with the establishment of normal patterns for hind paw placement during walking.

Rat Gestation During Space Flight: Outcomes for Dams and Their Offspring Born After Return to Earth

NASA Technical Reports Server (NTRS)

Wong, Andre M.; DeSantis, Mark

1997-01-01

Sprague-Dawley rats were studied to learn whether gestation in the near-zero gravity, high radiation environment of space impacts selected mammalian postnatal events. Ten rats spent days nine to twenty of pregnancy aboard the space shuttle orbiter Atlantis (STS-66). Their movement was studied shortly after return to Earth; subsequently, several of their offspring were cross-fostered and examined through postnatal day 81 (P81) for whole body growth and somatic motor development. Values for the flight animals were compared to ground-based control groups. Relative to controls, the pregnant flight rats showed a marked paucity of locomotion during the first few hours after returning to Earth. There was greater likelihood of perinatal morbidity for the offspring of flight dams when compared to the control groups. Whole body weight of surviving offspring, averaged for each group separately, showed typical sigmoidal growth curves when plotted against postnatal age. The flight group for our study had a larger ratio of female to male pups, and that was sufficient to account for the lower average daily weight gained by the flight animals when compared to the control groups. Walking was universally achieved by P13 and preceded eye opening, which was complete in all pups by P17. Thus, both of these developmental horizons were attained on schedule in the flight as well as the control rats. Characteristic changes were observed in hind limb step length and gait width as the pups grew. These patterns occurred at the same time in each group of rats. Therefore, prenatal space flight from days nine to twenty of gestation did not interfere with the establishment of normal patterns for hind paw placement during walking.

Shuttle orbiter boundary layer transition at flight and wind tunnel conditions

NASA Technical Reports Server (NTRS)

Goodrich, W. D.; Derry, S. M.; Bertin, J. J.

1983-01-01

Hypersonic boundary layer transition data obtained on the windward centerline of the Shuttle orbiter during entry for the first five flights are presented and analyzed. Because the orbiter surface is composed of a large number of thermal protection tiles, the transition data include the effects of distributed roughness arising from tile misalignment and gaps. These data are used as a benchmark for assessing and improving the accuracy of boundary layer transition predictions based on correlations of wind tunnel data taken on both aerodynamically rough and smooth orbiter surfaces. By comparing these two data bases, the relative importance of tunnel free stream noise and surface roughness on orbiter boundary layer transition correlation parameters can be assessed. This assessment indicates that accurate predications of transition times can be made for the orbiter at hypersonic flight conditions by using roughness dominated wind tunnel data. Specifically, times of transition onset and completion is accurately predicted using a correlation based on critical and effective values of a roughness Reynolds number previously derived from wind tunnel data.

Mission Control Center (MCC) System Specification for the Shuttle Orbital Flight Test (OFT) Timeframe

NASA Technical Reports Server (NTRS)

1976-01-01

System specifications to be used by the mission control center (MCC) for the shuttle orbital flight test (OFT) time frame were described. The three support systems discussed are the communication interface system (CIS), the data computation complex (DCC), and the display and control system (DCS), all of which may interfere with, and share processing facilities with other applications processing supporting current MCC programs. The MCC shall provide centralized control of the space shuttle OFT from launch through orbital flight, entry, and landing until the Orbiter comes to a stop on the runway. This control shall include the functions of vehicle management in the area of hardware configuration (verification), flight planning, communication and instrumentation configuration management, trajectory, software and consumables, payloads management, flight safety, and verification of test conditions/environment.

Mechanical failure probability of glasses in Earth orbit

NASA Technical Reports Server (NTRS)

Kinser, Donald L.; Wiedlocher, David E.

1992-01-01

Results of five years of earth-orbital exposure on mechanical properties of glasses indicate that radiation effects on mechanical properties of glasses, for the glasses examined, are less than the probable error of measurement. During the 5 year exposure, seven micrometeorite or space debris impacts occurred on the samples examined. These impacts were located in locations which were not subjected to effective mechanical testing, hence limited information on their influence upon mechanical strength was obtained. Combination of these results with micrometeorite and space debris impact frequency obtained by other experiments permits estimates of the failure probability of glasses exposed to mechanical loading under earth-orbit conditions. This probabilistic failure prediction is described and illustrated with examples.

Designing Delta-DOR acquisition strategies to determine highly elliptical earth orbits

NASA Technical Reports Server (NTRS)

Frauenholz, R. B.

1986-01-01

Delta-DOR acquisition strategies are designed for use in determining highly elliptical earth orbits. The requirements for a possible flight demonstration are evaluated for the Charged Composition Explorer spacecraft of the Active Magnetospheric Particle Tracer Explorers. The best-performing strategy uses data spanning the view periods of two orthogonal baselines near the same orbit periapse. The rapidly changing viewing geometry yields both angular position and velocity information, but each observation may require a different reference quasar. The Delta-DOR data noise is highly dependent on acquisition geometry, varying several orders of magnitude across the baseline view periods. Strategies are selected to minimize the measurement noise predicted by a theoretical model. Although the CCE transponder is limited by S-band and a small bandwidth, the addition of Delta-DOR to coherent Doppler and range improves the one-sigma apogee position accuracy by more than an order of magnitude. Additional Delta-DOR accuracy improvements possible using dual-frequency (S/X) calibration, increased spanned bandwidth, and water-vapor radiometry are presented for comparison. With these benefits, the residual Delta-DOR data noise is primarily due to quasar position uncertainties.

Ion beam sputter-deposited thin film coatings for protection of spacecraft polymers in low Earth orbit

NASA Technical Reports Server (NTRS)

Banks, B. A.; Mirtich, M. J.; Rutledge, S. K.; Swec, D. M.; Nahra, H. K.

1985-01-01

Ion beam sputter-deposited thin films of Al2O3, SiO2, and a codeposited mixture of predominantly SiO2 with small amounts of a fluoropolymer were evaluated both in laboratory plasma ashing tests and in space on board shuttle flight STS-8 for effectiveness in preventing oxidation of polyimide Kapton. Measurements of mass loss and optical performance of coated and uncoated polyimide samples exposed to the low Earth orbital environment are presented. Optical techniques were used to measure loss rates of protective films exposed to atomic oxygen. Results of the analysis of the space flight exposed samples indicate that thin film metal oxide coatings are very effective in protecting the polyimide. Metal oxide coatings with a small amount of fluoropolymer codeposited have the additional benefit of great flexibility.

Ion beam sputter-deposited thin film coatings for protection of spacecraft polymers in low earth orbit

NASA Technical Reports Server (NTRS)

Banks, B. A.; Mirtich, M. J.; Rutledge, S. K.; Swec, D. M.; Nahra, H. K.

1985-01-01

Ion beam sputter-deposited thin films at Al2O3, SiO2, and a codeposited mixture of predominantly SiO2 with small amounts of fluoropolymer were evaluated both in laboratory plasma ashing tests and in space on board Shuttle flight STS-8 for effectiveness in preventing oxidation of polyimide Kapton. Measurements of mass loss and optical performance of coated and uncoated polyimide samples exposed to the low earth orbital environment are presented. Optical techniques were used to measure loss rates of protective films exposed to atomic oxygen. Results of the analysis of the space flight exposed samples indicate that thin film metal oxide coatings are very effective in protecting the polyimide. Metal oxide coatings with a small amount of fluoropolymer codeposited have the additional benefit of great flexibility.

X-37 Flight Demonstrator: A Building Block in NASA's Future Access to Space

NASA Technical Reports Server (NTRS)

Jacobson, David

2004-01-01

X-37 is a fully automated winged vehicle designed to go into low-Earth orbit, maneuver, reenter Earth's atmosphere, and glide back to a landing site. This viewgraph presentation gives an overview of the X-37 flight demonstrator, including cut-away diagrams of its interior, the phased approach to its orbital flight demonstrations, and the experience the program will give aerospace engineers. The presentation also lists X-37 applications, partners, and milestones.

NASA's CSTI Earth-to-Orbit Propulsion Program - On-target technology transfer to advanced space flight programs

NASA Technical Reports Server (NTRS)

Escher, William J. D.; Herr, Paul N.; Stephenson, Frank W., Jr.

1990-01-01

NASA's Civil Space Technology Initiative encompasses among its major elements the Earth-to-Orbit Propulsion Program (ETOPP) for future launch vehicles, which is budgeted to the extent of $20-30 million/year for the development of essential technologies. ETOPP technologies include, in addition to advanced materials and processes and design/analysis computational tools, the advanced systems-synthesis technologies required for definition of highly reliable LH2 and hydrocarbon fueled rocket engines to be operated at significantly reduced levels of risk and cost relative to the SSME. Attention is given to the technology-transfer services of ETOPP.

Decomposition technique and optimal trajectories for the aeroassisted flight experiment

NASA Technical Reports Server (NTRS)

Miele, A.; Wang, T.; Deaton, A. W.

1990-01-01

An actual geosynchronous Earth orbit-to-low Earth orbit (GEO-to-LEO) transfer is considered with reference to the aeroassisted flight experiment (AFE) spacecraft, and optimal trajectories are determined by minimizing the total characteristic velocity. The optimization is performed with respect to the time history of the controls (angle of attack and angle of bank), the entry path inclination and the flight time being free. Two transfer maneuvers are considered: direct ascent (DA) to LEO and indirect ascent (IA) to LEO via parking Earth orbit (PEO). By taking into account certain assumptions, the complete system can be decoupled into two subsystems: one describing the longitudinal motion and one describing the lateral motion. The angle of attack history, the entry path inclination, and the flight time are determined via the longitudinal motion subsystem. In this subsystem, the difference between the instantaneous bank angle and a constant bank angle is minimized in the least square sense subject to the specified orbital inclination requirement. Both the angles of attack and the angle of bank are shown to be constant. This result has considerable importance in the design of nominal trajectories to be used in the guidance of AFE and aeroassisted orbital transfer (AOT) vehicles.

Thin-Film Solar Array Earth Orbit Mission Applicability Assessment

NASA Technical Reports Server (NTRS)

Hoffman, David J.; Kerslake, Thomas W.; Hepp, Aloysius F.; Raffaelle, Ryne P.

2002-01-01

This is a preliminary assessment of the applicability and spacecraft-level impact of using very lightweight thin-film solar arrays with relatively large deployed areas for representative Earth orbiting missions. The most and least attractive features of thin-film solar arrays are briefly discussed. A simple calculation is then presented illustrating that from a solar array alone mass perspective, larger arrays with less efficient but lighter thin-film solar cells can weigh less than smaller arrays with more efficient but heavier crystalline cells. However, a proper spacecraft-level systems assessment must take into account the additional mass associated with solar array deployed area: the propellant needed to desaturate the momentum accumulated from area-related disturbance torques and to perform aerodynamic drag makeup reboost. The results for such an assessment are presented for a representative low Earth orbit (LEO) mission, as a function of altitude and mission life, and a geostationary Earth orbit (GEO) mission. Discussion of the results includes a list of specific mission types most likely to benefit from using thin-film arrays. NASA Glenn's low-temperature approach to depositing thin-film cells on lightweight, flexible plastic substrates is also briefly discussed to provide a perspective on one approach to achieving this enabling technology. The paper concludes with a list of issues to be addressed prior to use of thin-film solar arrays in space and the observation that with their unique characteristics, very lightweight arrays using efficient, thin-film cells on flexible substrates may become the best array option for a subset of Earth orbiting missions.

Low-energy near Earth asteroid capture using Earth flybys and aerobraking

NASA Astrophysics Data System (ADS)

Tan, Minghu; McInnes, Colin; Ceriotti, Matteo

2018-04-01

Since the Sun-Earth libration points L1 and L2 are regarded as ideal locations for space science missions and candidate gateways for future crewed interplanetary missions, capturing near-Earth asteroids (NEAs) around the Sun-Earth L1/L2 points has generated significant interest. Therefore, this paper proposes the concept of coupling together a flyby of the Earth and then capturing small NEAs onto Sun-Earth L1/L2 periodic orbits. In this capture strategy, the Sun-Earth circular restricted three-body problem (CRTBP) is used to calculate target Lypaunov orbits and their invariant manifolds. A periapsis map is then employed to determine the required perigee of the Earth flyby. Moreover, depending on the perigee distance of the flyby, Earth flybys with and without aerobraking are investigated to design a transfer trajectory capturing a small NEA from its initial orbit to the stable manifolds associated with Sun-Earth L1/L2 periodic orbits. Finally, a global optimization is carried out, based on a detailed design procedure for NEA capture using an Earth flyby. Results show that the NEA capture strategies using an Earth flyby with and without aerobraking both have the potential to be of lower cost in terms of energy requirements than a direct NEA capture strategy without the Earth flyby. Moreover, NEA capture with an Earth flyby also has the potential for a shorter flight time compared to the NEA capture strategy without the Earth flyby.

Investigating fundamental physics and space environment with a dedicated Earth-orbiting spacecraft

NASA Astrophysics Data System (ADS)

Peron, Roberto

The near-Earth environment is a place of first choice for performing fundamental physics experiments, given its proximity to Earth and at the same time being relatively quiet dynamically for particular orbital arrangements. This environment also sees a rich phenomenology for what concerns gravitation. In fact, the general theory of relativity is an incredibly accurate description of gravitational phenomenology. However, its overall validity is being questioned by the theories that aim at reconciling it with the microscopic domain. Challenges come also from the ‘mysteries’ of Dark Matter and Dark Energy, though mainly at scales from the galactic up to the cosmological. It is therefore important to precisely test the consequences of the theory -- as well as those of competing ones -- at all the accessible scales. At the same time, the development of high-precision experimental space techniques, which are needed for tests in fundamental physics, opens the way to complementary applications. The growth of the (man-made) orbital debris population is creating problems to the future development of space. The year 2009 witnessed the first accidental collision between two satellites in orbit (Iridium and Cosmos) that led to the creation of more debris. International and national agencies are intervening by issuing and/or adopting guidelines to mitigate the growth of orbital debris. A central tenet of these guidelines requires a presence in space shorter than 25 years to satellites in low Earth orbit (LEO) after the conclusion of their operational lives. However, the determination of the natural lifetime of a satellite in LEO is very uncertain due to a large extent to the short-term and long-term variability of the atmospheric density in LEO and the comparatively low-accuracy of atmospheric density models. Many satellites orbiting in the 500-1200 km region with circular or elliptical orbits will be hard pressed to establish before flight whether or not they meet the 25

Horowitz checks flight notes at the commander's station

NASA Image and Video Library

2001-08-10

STS105-E-5002 (10 August 2001) --- Astronaut Scott J. Horowitz, STS-105 commander, checks flight notes at the commander's station on the flight deck of the Earth-orbiting Space Shuttle Discovery. The image was recorded with a digital still camera.

Horowitz checks flight notes at the commander's station

NASA Image and Video Library

2001-08-10

STS105-E-5001 (10 August 2001) --- Astronaut Scott J. Horowitz, STS-105 commander, checks flight notes at the commander's station on the flight deck of the Earth-orbiting Space Shuttle Discovery. The image was recorded with a digital still camera.

Flight Project Data Book

NASA Technical Reports Server (NTRS)

1992-01-01

The Office of Space Science and Applications (OSSA) is responsible for the overall planning, directing, executing, and evaluating that part of the overall NASA program that has the goal of using the unique characteristics of the space environment to conduct a scientific study of the universe, to understand how the Earth works as an integrated system, to solve practical problems on Earth, and to provide the scientific and technological research foundation for expanding human presence beyond Earth orbit into the solar system. OSSA guides its program toward leadership through its pursuit of excellence across the full spectrum of disciplines. OSSA pursues these goals through an integrated program of ground-based laboratory research and experimentation, suborbital flight of instruments on airplanes, balloons, and sounding rockets; flight of instruments and the conduct of research on the Shuttle/Spacelab system and on Space Station Freedom; and development and flight of automated Earth-orbiting and interplanetary spacecraft. The OSSA program is conducted with the participation and support of other Government agencies and facilities, universities throughout the United States, the aerospace contractor community, and all of NASA's nine Centers. In addition, OSSA operates with substantial international participation in many aspects of our Space Science and Applications Program. OSSA's programs currently in operation, those approved for development, and those planned for future missions are described.

Design considerations for space flight hardware

NASA Technical Reports Server (NTRS)

Glover, Daniel

1990-01-01

The environmental and design constraints are reviewed along with some insight into the established design and quality assurance practices that apply to low earth orbit (LEO) space flight hardware. It is intended as an introduction for people unfamiliar with space flight considerations. Some basic data and a bibliography are included.

NASA Earth-to-Orbit Engineering Design Challenges: Thermal Protection Systems

ERIC Educational Resources Information Center

National Aeronautics and Space Administration (NASA), 2010

2010-01-01

National Aeronautics and Space Administration (NASA) Engineers at Marshall Space Flight Center, Dryden Flight Research Center, and their partners at other NASA centers and in private industry are currently developing X-33, a prototype to test technologies for the next generation of space transportation. This single-stage-to-orbit reusable launch…

Use of the VLBI delay observable for orbit determination of Earth-orbiting VLBI satellites

NASA Technical Reports Server (NTRS)

Ulvestad, J. S.

1992-01-01

Very long-baseline interferometry (VLBI) observations using a radio telescope in Earth orbit were performed first in the 1980s. Two spacecraft dedicated to VLBI are scheduled for launch in 1995; the primary scientific goals of these missions will be astrophysical in nature. This article addresses the use of space VLBI delay data for the additional purpose of improving the orbit determination of the Earth-orbiting spacecraft. In an idealized case of quasi-simultaneous observations of three radio sources in orthogonal directions, analytical expressions are found for the instantaneous spacecraft position and its error. The typical position error is at least as large as the distance corresponding to the delay measurement accuracy but can be much greater for some geometries. A number of practical considerations, such as system noise and imperfect calibrations, set bounds on the orbit-determination accuracy realistically achievable using space VLBI delay data. These effects limit the spacecraft position accuracy to at least 35 cm (and probably 3 m or more) for the first generation of dedicated space VLBI experiments. Even a 35-cm orbital accuracy would fail to provide global VLBI astrometry as accurate as ground-only VLBI. Recommended charges in future space VLBI missions are unlikely to make space VLBI competitive with ground-only VLBI in global astrometric measurements.

Closeup view of the aft flight deck of the Orbiter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close-up view of the aft flight deck of the Orbiter Discovery looking at the aft center control panels A6, A7, A8, A12, A13, A14, A16 and A17. This View was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

Ohio Senator John Glenn tours the orbiter Columbia's middeck

NASA Technical Reports Server (NTRS)

1998-01-01

Ohio Senator John Glenn, at right, sits in the flight deck of the orbiter Columbia as astronaut Stephen Oswald listens to his questions regarding some of the flight equipment at the Orbiter Processing Facility 3 at Kennedy Space Center. Senator Glenn arrived at KSC on Jan. 20 to tour KSC operational areas and to view the launch of STS-89 later this week. Glenn, who made history in 1962 as the first American to orbit the Earth, completing three orbits in a five-hour flight aboard Friendship 7, will fly his second space mission aboard Space Shuttle Discovery this October. Glenn is retiring from the Senate at the end of this year and will be a payload specialist aboard STS-95.

Studies of neutron and proton nuclear activation in low-Earth orbit

NASA Technical Reports Server (NTRS)

Laird, C. E.

1982-01-01

The expected induced radioactivity of experimental material in low Earth orbit was studied for characteristics of activating particles such as cosmic rays, high energy Earth albedo neutrons, trapped protons, and secondary protons and neutrons. The activation cross sections for the production of long lived radioisotopes and other existing nuclear data appropriate to the study of these reactions were compiled. Computer codes which are required to calculate the expected activation of orbited materials were developed. The decreased computer code used to predict the activation of trapped protons of materials placed in the expected orbits of LDEF and Spacelab II. Techniques for unfolding the fluxes of activating particles from the measured activation of orbited materials are examined.

Earth Albedo and the orbit of LAGEOS

NASA Technical Reports Server (NTRS)

Rubincam, D. P.; Weiss, N. R.

1985-01-01

The long-period perturbations in the orbit of the Lageos satellite due to the Earth's albedo have been found using a new analytical formalism. The Earth is assumed to be a sphere whose surface diffusely reflects sunlight according to Lambert's law. Specular reflection is not considered. The formalism is based on spherical harmonics; it produces equations which hold regardless of whether the terminator is seen by the satellite or not. Specializing to the case of a realistic zonal albedo shows that Lageos' orbital semimajor axis changes periodically by only the a few millimeters and the eccentricity by one part in 100,000. The longitude of the node increases secularly. The effect considered here can explain neither the secular decay of 1.1 mm/day in the semimajor axis nor the observed along-track variations in acceleration of order 2 x 10 to the minus 12 power/sq ms.

Earth albedo and the orbit of Lageos

NASA Technical Reports Server (NTRS)

Rubincam, D. P.; Weiss, N. S.

1986-01-01

The long-period perturbations in the orbit of the Lageos satellite due to the Earth's albedo have been found using a new analytical formalism. The Earth is assumed to be a sphere whose surface diffusely reflects sunlight according to Lambert's law. Specular reflection is not considered. The formalism is based on spherical harmonics; it produces equations which hold regardless of whether the terminator is seen by the satellite or not. Specializing to the case of a realistic zonal albedo shows that Lageos' orbital semimajor axis changes periodically by only a few millimeters and the eccentricity by one part in 100,000. The longitude of the node increases secularly. The effect considered here can explain neither the secular decay of 1.1 mm/day in the semimajor axis nor the observed along-track variations in acceleration of order 2 x 10 to the minus 12 power/sq ms.

On-orbit stability and performance of the Clouds and Earth's Radiant Energy System (CERES) instrument sensors onboard the Aqua and Terra Spacecraft

NASA Astrophysics Data System (ADS)

Shankar, Mohan; Priestley, Kory; Smith, Nitchie; Thomas, Susan; Walikainen, Dale

2014-09-01

The Clouds and Earth's Radiant Energy System (CERES) instruments onboard the Terra and Aqua spacecraft are part of the NASA Earth Observing System (EOS) constellation to make long-term observations of the earth. CERES measures the earth-reflected shortwave energy as well as the earth-emitted thermal energy, which are two components of the earth's radiation energy budget. These measurements are made by five instruments- Flight Models (FM) 1 and 2 onboard Terra, FMs 3 and 4 onboard Aqua and FM5 onboard Suomi NPP. Each instrument comprises three sensors that measure the radiances in different wavelength bands- a shortwave sensor that measures in the 0.3 to 5 micron band, a total sensor that measures all the incident energy (0.3-200 microns) and a window sensor that measures the water-vapor window region of 8 to 12 microns. The stability of the sensors is monitored through on-orbit calibration and validation activities. On-orbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors' broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for FM1-FM4 incorporate the latest corrections to the sensor responses using the calibration techniques. In this paper, we present the on-orbit performance stability as well as some validation studies used in deriving the CERES Edition-4 data products from all four instruments.

Coding performance of the Probe-Orbiter-Earth communication link

NASA Technical Reports Server (NTRS)

Divsalar, D.; Dolinar, S.; Pollara, F.

1993-01-01

The coding performance of the Probe-Orbiter-Earth communication link is analyzed and compared for several cases. It is assumed that the coding system consists of a convolutional code at the Probe, a quantizer and another convolutional code at the Orbiter, and two cascaded Viterbi decoders or a combined decoder on the ground.

Advanced Earth-to-orbit propulsion technology program overview: Impact of civil space technology initiative

NASA Technical Reports Server (NTRS)

Stephenson, Frank W., Jr.

1988-01-01

The NASA Earth-to-Orbit (ETO) Propulsion Technology Program is dedicated to advancing rocket engine technologies for the development of fully reusable engine systems that will enable space transportation systems to achieve low cost, routine access to space. The program addresses technology advancements in the areas of engine life extension/prediction, performance enhancements, reduced ground operations costs, and in-flight fault tolerant engine operations. The primary objective is to acquire increased knowledge and understanding of rocket engine chemical and physical processes in order to evolve more realistic analytical simulations of engine internal environments, to derive more accurate predictions of steady and unsteady loads, and using improved structural analyses, to more accurately predict component life and performance, and finally to identify and verify more durable advanced design concepts. In addition, efforts were focused on engine diagnostic needs and advances that would allow integrated health monitoring systems to be developed for enhanced maintainability, automated servicing, inspection, and checkout, and ultimately, in-flight fault tolerant engine operations.

Space Shuttle program orbital flight test program results and implications

NASA Technical Reports Server (NTRS)

Kohrs, R. H.

1982-01-01

The Space Shuttle System Orbital Flight Test (OFT) program results are described along with an overview of significant development issues and their resolution. In addition, an overall summary of the development status and the follow-on flight demonstrations of Shuttle improvements such as Lightweight External Tank, High Performance SRBs, Full Power Level (109%) Main Engine Operation, and the SRB Filament Wound Case (FWC) will be discussed.

Electric Propulsion for Low Earth Orbit Communication Satellites

NASA Technical Reports Server (NTRS)

Oleson, Steven R.

1997-01-01

Electric propulsion was evaluated for orbit insertion, satellite positioning and de-orbit applications on big (hundreds of kilograms) and little (tens of kilograms) low earth orbit communication satellite constellations. A simple, constant circumferential thrusting method was used. This technique eliminates the complex guidance and control required when shading of the solar arrays must be considered. Power for propulsion was assumed to come from the existing payload power. Since the low masses of these satellites enable multiple spacecraft per launch, the ability to add spacecraft to a given launch was used as a figure of merit. When compared to chemical propulsion ammonia resistojets, ion, Hall, and pulsed plasma thrusters allowed an additional spacecraft per launch Typical orbit insertion and de-orbit times were found to range from a few days to a few months.

Enterprise - First Tailcone Off Free Flight

NASA Technical Reports Server (NTRS)

1977-01-01

The Space Shuttle prototype Enterprise flies free after being released from NASA's 747 Shuttle Carrier Aircraft (SCA) to begin a powerless glide flight back to NASA's Dryden Flight Research Center, Edwards, California, on its fourth of the five free flights in the Shuttle program's Approach and Landing Tests (ALT), 12 October 1977. The tests were carried out at Dryden to verify the aerodynamic and control characteristics of the orbiters in preperation for the first space mission with the orbiter Columbia in April 1981. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay throughout the mission. They are then removed after the Space Shuttle returns to Earth and can be reused on future flights. Some of these orbital laboratories, like the Spacelab, provide

Size Dependence of Dust Distribution around the Earth Orbit

NASA Astrophysics Data System (ADS)

Ueda, Takahiro; Kobayashi, Hiroshi; Takeuchi, Taku; Ishihara, Daisuke; Kondo, Toru; Kaneda, Hidehiro

2017-05-01

In the solar system, interplanetary dust particles (IDPs) originating mainly from asteroid collisions and cometary activities drift to Earth orbit due to Poynting-Robertson drag. We analyzed the thermal emission from IDPs that was observed by the first Japanese infrared astronomical satellite, AKARI. The observed surface brightness in the trailing direction of the Earth orbit is 3.7% greater than that in the leading direction in the 9 μm band and 3.0% in the 18 μm band. In order to reveal dust properties causing leading-trailing surface brightness asymmetry, we numerically integrated orbits of the Sun, the Earth, and a dust particle as a restricted three-body problem including radiation from the Sun. The initial orbits of particles are determined according to the orbits of main-belt asteroids or Jupiter-family comets. Orbital trapping in mean motion resonances results in a significant leading-trailing asymmetry so that intermediate sized dust (˜10-100 μm) produces a greater asymmetry than zodiacal light. The leading-trailing surface brightness difference integrated over the size distribution of the asteroidal dust is obtained to be 27.7% and 25.3% in the 9 μm and 18 μm bands, respectively. In contrast, the brightness difference for cometary dust is calculated as 3.6% and 3.1% in the 9 μm and 18 μm bands, respectively, if the maximum dust radius is set to be s max = 3000 μm. Taking into account these values and their errors, we conclude that the contribution of asteroidal dust to the zodiacal infrared emission is less than ˜10%, while cometary dust of the order of 1 mm mainly accounts for the zodiacal light in infrared.

Size Dependence of Dust Distribution around the Earth Orbit

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

Ueda, Takahiro; Takeuchi, Taku; Kobayashi, Hiroshi

In the solar system, interplanetary dust particles (IDPs) originating mainly from asteroid collisions and cometary activities drift to Earth orbit due to Poynting–Robertson drag. We analyzed the thermal emission from IDPs that was observed by the first Japanese infrared astronomical satellite, AKARI . The observed surface brightness in the trailing direction of the Earth orbit is 3.7% greater than that in the leading direction in the 9 μ m band and 3.0% in the 18 μ m band. In order to reveal dust properties causing leading–trailing surface brightness asymmetry, we numerically integrated orbits of the Sun, the Earth, and amore » dust particle as a restricted three-body problem including radiation from the Sun. The initial orbits of particles are determined according to the orbits of main-belt asteroids or Jupiter-family comets. Orbital trapping in mean motion resonances results in a significant leading–trailing asymmetry so that intermediate sized dust (∼10–100 μ m) produces a greater asymmetry than zodiacal light. The leading–trailing surface brightness difference integrated over the size distribution of the asteroidal dust is obtained to be 27.7% and 25.3% in the 9 μ m and 18 μ m bands, respectively. In contrast, the brightness difference for cometary dust is calculated as 3.6% and 3.1% in the 9 μ m and 18 μ m bands, respectively, if the maximum dust radius is set to be s {sub max} = 3000 μ m. Taking into account these values and their errors, we conclude that the contribution of asteroidal dust to the zodiacal infrared emission is less than ∼10%, while cometary dust of the order of 1 mm mainly accounts for the zodiacal light in infrared.« less

NASA/Boeing Orbital Test Flight Simulation

NASA Image and Video Library

2018-03-07

NASA, Boeing and United Launch Alliance (ULA) conduct a simulation of launch procedures for Boeing’s Orbital Test Flight, the first uncrewed test of the company’s CST-100 Starliner and a ULA Atlas V rocket. Launch teams participated in the simulation across the country, including inside the Launch Vehicle Data Center at Hangar AE at Cape Canaveral Air Force Station in Florida. The Starliner will launch on an Atlas V rocket to the International Space Station as part of NASA’s Commercial Crew Program.

Stationkeeping of the First Earth-Moon Libration Orbiters: The ARTEMIS Mission

NASA Technical Reports Server (NTRS)

Folta, David; Woodard, Mark; Cosgrove, D.

2011-01-01

Libration point orbits near collinear locations are inherently unstable and must be controlled. For Acceleration Reconnection and Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) Earth-Moon Lissajous orbit operations, stationkeeping is challenging because of short time scales, large orbital eccentricity of the secondary, and solar gravitational and radiation pressure perturbations. ARTEMIS is the first NASA mission continuously controlled at both Earth-Moon L1 and L2 locations and uses a balance of optimization, spacecraft implementation and constraints, and multi-body dynamics. Stationkeeping results are compared to pre-mission research including mode directions.

Dynamical Sequestration of the Moon-Forming Impactor in Co-Orbital Resonance with Earth

NASA Astrophysics Data System (ADS)

Kortenkamp, Stephen J.; Hartmann, William J.

2015-11-01

Recent concerns about the giant impact hypothesis for the origin of the moon, and an associated “isotope crisis” are assuaged if the impactor was a local object that formed near Earth and the impact occurred relatively late. We investigated a scenario that may meet these criteria, with the moon-forming impactor originating in 1:1 co-orbital resonance with Earth. Using N-body numerical simulations we explored the dynamical consequences of placing Mars-mass companions in various co-orbital configurations with a proto-Earth having 90% of its current mass. We modeled configurations that include the four terrestrial planets as well as configurations that also include the four giant planets. In both the 4- and 8-planet models we found that a single additional Mars-mass companion typically remains a stable co-orbital of Earth for the entire 250 million year (Myr) duration of our simulations (33 of 34 simulations). In an effort to destabilize such a system we carried out an additional 45 simulations that included a second Mars-mass co-orbital companion. Even with two Mars-mass companions sharing Earth’s orbit most of these models (28) also remained stable for the entire 250 Myr duration of the simulations. Of the 17 two-companion models that eventually became unstable 12 impacts were observed between Earth and an escaping co-orbital companion. The average delay we observed for an impact of a Mars-mass companion with Earth was 101 Myr, and the longest delay was 221 Myr. Several of the stable simulations involved unusual 3-planet co-orbital configurations that could exhibit interesting observational signatures in plantetary transit surveys.

Pulsed Plasma Propulsion - Making CubeSat Missions Beyond Low Earth Orbit Possible

NASA Astrophysics Data System (ADS)

Northway, P.

2015-12-01

As CubeSat missions become more and more popular means of scientific exploration of space, the current direction of interest is to utilize them in areas beyond low earth orbit. The University of Washington CubeSat program focuses on examining possible mission scenarios in addition to technology development and integration. Specifically, we are developing an inert CubeSat propulsion system in the form of a pulsed plasma thruster (PPT) capable of orbit maneuvers. Such a system would allow for missions at the Earth beyond LEO, extended missions at the Moon, and even missions at Europa, when assisted to the Jovian system. We will discuss how starting with a CubeSat design using PPTs for orbital maneuvers, other developing compact technology can be adapted to create a full suite of systems that would meet the requirements for a mission traveling outside low earth orbit.

Launching Social Studies into Orbit.

ERIC Educational Resources Information Center

Stone, Kirk

1986-01-01

As a social studies educator, Christa McAuliffe was delighted that a "non-science teacher" was chosen to become the first teacher to orbit the earth. Her thoughts concerning the NASA space flight and its meaning for the social studies are discussed. (RM)

Simulation of Micron-Sized Debris Populations in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Xu, Y.-L.; Hyde, J. L.; Prior, T.; Matney, Mark

2010-01-01

The update of ORDEM2000, the NASA Orbital Debris Engineering Model, to its new version ORDEM2010, is nearly complete. As a part of the ORDEM upgrade, this paper addresses the simulation of micro-debris (greater than 10 m and smaller than 1 mm in size) populations in low Earth orbit. The principal data used in the modeling of the micron-sized debris populations are in-situ hypervelocity impact records, accumulated in post-flight damage surveys on the space-exposed surfaces of returned spacecrafts. The development of the micro-debris model populations follows the general approach to deriving other ORDEM2010-required input populations for various components and types of debris. This paper describes the key elements and major steps in the statistical inference of the ORDEM2010 micro-debris populations. A crucial step is the construction of a degradation/ejecta source model to provide prior information on the micron-sized objects (such as orbital and object-size distributions). Another critical step is to link model populations with data, which is rather involved. It demands detailed information on area-time/directionality for all the space-exposed elements of a shuttle orbiter and damage laws, which relate impact damage with the physical properties of a projectile and impact conditions such as impact angle and velocity. Also needed are model-predicted debris fluxes as a function of object size and impact velocity from all possible directions. In spite of the very limited quantity of the available shuttle impact data, the population-derivation process is satisfactorily stable. Final modeling results obtained from shuttle window and radiator impact data are reasonably convergent and consistent, especially for the debris populations with object-size thresholds at 10 and 100 m.

Simulation of Micron-Sized Debris Populations in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Xu, Y.-L.; Matney, M.; Liou, J.-C.; Hyde, J. L.; Prior, T. G.

2010-01-01

The update of ORDEM2000, the NASA Orbital Debris Engineering Model, to its new version . ORDEM2010, is nearly complete. As a part of the ORDEM upgrade, this paper addresses the simulation of micro-debris (greater than 10 micron and smaller than 1 mm in size) populations in low Earth orbit. The principal data used in the modeling of the micron-sized debris populations are in-situ hypervelocity impact records, accumulated in post-flight damage surveys on the space-exposed surfaces of returned spacecrafts. The development of the micro-debris model populations follows the general approach to deriving other ORDEM2010-required input populations for various components and types of debris. This paper describes the key elements and major steps in the statistical inference of the ORDEM2010 micro-debris populations. A crucial step is the construction of a degradation/ejecta source model to provide prior information on the micron-sized objects (such as orbital and object-size distributions). Another critical step is to link model populations with data, which is rather involved. It demands detailed information on area-time/directionality for all the space-exposed elements of a shuttle orbiter and damage laws, which relate impact damage with the physical properties of a projectile and impact conditions such as impact angle and velocity. Also needed are model-predicted debris fluxes as a function of object size and impact velocity from all possible directions. In spite of the very limited quantity of the available shuttle impact data, the population-derivation process is satisfactorily stable. Final modeling results obtained from shuttle window and radiator impact data are reasonably convergent and consistent, especially for the debris populations with object-size thresholds at 10 and 100 micron.

STS-120 Flight Controllers on console during mission

NASA Image and Video Library

2007-10-31

JSC2007-E-095788 (3 Nov. 2007) --- Flight directors Norm Knight (left) and Bryan Lunney, inside the shuttle flight control room of JSC's Mission Control Center, monitor the progress of the Nov. 3 spacewalk by two members of Discovery's crew, while the space shuttle is docked with the International Space Station in Earth orbit. Astronaut Scott Parazynski was busy at work on repairing a tear in a solar panel on the orbiting outpost.

Ancient Earth, Alien Earths Event

NASA Image and Video Library

2014-08-20

Dr. Shawn Domagal-Goldman, Research Space Scientist, NASA Goddard Space Flight Center, speaks on a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

Launch vehicles of the future - Earth to near-earth space

NASA Astrophysics Data System (ADS)

Keyworth, G. A., II

Attention is given to criteria for launch vehicles of the future, namely, cost, flexibility of payload size, and routine access to space. The National Aerospace Plane (NASP), an airplane designed to achieve hypersonic speeds using a sophisticated air-breathing engine, is argued to meet these criteria. Little additional oxygen is needed to enter low-earth orbit, and it will return to an airport runway under powered flight. Cost estimates for a NASP-derived vehicle are two to five million dollars for a payload of 20,000 to 30,000 pounds to orbit. For the Shuttle, a comparable payload is nominally about 150 million dollars. NASP estimates for the new single-stage-to-orbit designs are substantially lower than existing launch costs. The NASP also offers fast turnaround and minimal logistics. Access to virtually all near-earth orbits will be provided as well.

Orbit determination support of the Ocean Topography Experiment (TOPEX)/Poseidon operational orbit

NASA Technical Reports Server (NTRS)

Schanzle, A. F.; Rovnak, J. E.; Bolvin, D. T.; Doll, C. E.

1993-01-01

The Ocean Topography Experiment (TOPEX/Poseidon) mission is designed to determine the topography of the Earth's sea surface over a 3-year period, beginning shortly after launch in July 1992. TOPEX/Poseidon is a joint venture between the United States National Aeronautics and Space Administration (NASA) and the French Centre Nationale d'Etudes Spatiales. The Jet Propulsion Laboratory is NASA's TOPEX/Poseidon project center. The Tracking and Data Relay Satellite System (TDRSS) will nominally be used to support the day-to-day orbit determination aspects of the mission. Due to its extensive experience with TDRSS tracking data, the NASA Goddard Space Flight Center (GSFC) Flight Dynamics Facility (FDF) will receive and process TDRSS observational data. To fulfill the scientific goals of the mission, it is necessary to achieve and maintain a very precise orbit. The most stringent accuracy requirements are associated with planning and evaluating orbit maneuvers, which will place the spacecraft in its mission orbit and maintain the required ground track. To determine if the FDF can meet the TOPEX/Poseidon maneuver accuracy requirements, covariance analysis was undertaken with the Orbit Determination Error Analysis System (ODEAS). The covariance analysis addressed many aspects of TOPEX/Poseidon orbit determination, including arc length, force models, and other processing options. The most recent analysis has focused on determining the size of the geopotential field necessary to meet the maneuver support requirements. Analysis was undertaken with the full 50 x 50 Goddard Earth Model (GEM) T3 field as well as smaller representations of this model.

Orbit and size distributions for asteroids temporarily captured by the Earth-Moon system

NASA Astrophysics Data System (ADS)

Fedorets, Grigori; Granvik, Mikael; Jedicke, Robert

2017-03-01

As a continuation of the work by Granvik et al. (2012), we expand the statistical treatment of Earth's temporarily-captured natural satellites from temporarily-captured orbiters (TCOs, i.e., objects which make at least one orbit around the Earth) to the newly redefined subpopulation of temporarily-captured flybys (TCFs). TCFs are objects that while being gravitationally bound fail to make a complete orbit around the Earth while on a geocentric orbit, but nevertheless approach the Earth within its Hill radius. We follow the trajectories of massless test asteroids through the Earth-Moon system and record the orbital characteristics of those that are temporarily captured. We then carry out a steady-state analysis utilizing the novel NEO population model by Granvik et al. (2016). We also investigate how an quadratic distribution at very small values of e⊙ and i⊙ affects the predicted population statistics of Earth's temporarily-captured natural satellites. The steady-state population in both cases (constant and quadratic number distributions inside the e and i bins) is predicted to contain a slightly reduced number of meter-sized asteroids compared to the values of the previous paper. For the combined TCO/TCF population, we find the largest body constantly present on a geocentric orbit to be on the order of 80 cm in diameter. In the phase space, where the capture is possible, the capture efficiency of TCOs and TCFs is O(10-6 -10-4) . We also find that kilometer-scale asteroids are captured once every 10 Myr.

General view of the flight deck of the Orbiter Discovery ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

General view of the flight deck of the Orbiter Discovery looking forward from behind the commander's seat looking towards the pilot's station. Note the numerous Velcro pads located throughout the crew compartment, used to secure frequently used items when in zero gravity. This image was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

Development of dedicated target tracking capability for the CERES instruments through flight software: enhancing radiometric validation and on-orbit calibration

NASA Astrophysics Data System (ADS)

Teague, Kelly K.; Smith, G. Louis; Priestley, Kory; Lukashin, Constantine; Roithmayr, Carlos

2012-09-01

Five CERES scanning radiometers have been flown to date. The Proto-Flight Model flew aboard the Tropical Rainfall Measurement Mission spacecraft in November 1997. Two CERES instruments, Flight Models (FM) 1 and 2, are aboard the Terra spacecraft, which was launched in December 1999. Two more CERES instruments, FM-3 and FM-4, are on the Aqua spacecraft, which was placed in orbit in May 2002. These instruments continue to operate after providing over a decade of Earth Radiation Budget data. The CERES FM-5 instrument, onboard the Suomi-NPP spacecraft, launched in October 2011. The CERES FM- 6 instrument is manifested on the JPPS-1 spacecraft to be launched in December 2016. A successor to these instruments is presently in the definition stage. This paper describes the evolving role of flight software in the operation of these instruments to meet the Science objectives of the mission and also the ability to execute supplemental tasks as they evolve. In order to obtain and maintain high accuracy in the data products from these instruments, a number of operational activities have been developed and implemented since the instruments were originally designed and placed in orbit. These new activities are possible because of the ability to exploit and modify the flight software, which operates the instruments. The CERES Flight Software interface was designed to allow for on-orbit modification, and as such, constantly evolves to meet changing needs. The purpose of this paper is to provide a brief overview of modifications which have been developed to allow dedicated targeting of specific geographic locations as the CERES sensor flies overhead on its host spacecraft. This new observing strategy greatly increases the temporal and angular sampling for specific targets of high scientific interest.

Space shuttle on-orbit flight control software requirements, preliminary version

NASA Technical Reports Server (NTRS)

1975-01-01

Software modules associated with various flight control functions for the space shuttle orbiter are described. Data flow, interface requirements, initialization requirements and module sequencing requirements are considered. Block diagrams and tables are included.

Earth observations taken from shuttle orbiter Columbia

NASA Image and Video Library

1995-10-22

STS073-728-010 (22 October 1995) --- Photographed by the astronauts aboard the Space Shuttle Columbia orbiting at 146 nautical miles above Earth is this scene over West Virginia featuring the Appalachian Mountains. Center point coordinates are 37.5 degrees north latitude and 80.5 degrees west longitude.

Horizon: A Proposal for Large Aperture, Active Optics in Geosynchronous Orbit

NASA Technical Reports Server (NTRS)

Chesters, Dennis; Jenstrom, Del

2000-01-01

In 1999, NASA's New Millennium Program called for proposals to validate new technology in high-earth orbit for the Earth Observing-3 (NMP EO3) mission to fly in 2003. In response, we proposed to test a large aperture, active optics telescope in geosynchronous orbit. This would flight-qualify new technologies for both Earth and Space science: 1) a future instrument with LANDSAT image resolution and radiometric quality watching continuously from geosynchronous station, and 2) the Next Generation Space Telescope (NGST) for deep space imaging. Six enabling technologies were to be flight-qualified: 1) a 3-meter, lightweight segmented primary mirror, 2) mirror actuators and mechanisms, 3) a deformable mirror, 4) coarse phasing techniques, 5) phase retrieval for wavefront control during stellar viewing, and 6) phase diversity for wavefront control during Earth viewing. Three enhancing technologies were to be flight- validated: 1) mirror deployment and latching mechanisms, 2) an advanced microcontroller, and 3) GPS at GEO. In particular, two wavefront sensing algorithms, phase retrieval by JPL and phase diversity by ERIM International, were to sense optical system alignment and focus errors, and to correct them using high-precision mirror mechanisms. Active corrections based on Earth scenes are challenging because phase diversity images must be collected from extended, dynamically changing scenes. In addition, an Earth-facing telescope in GEO orbit is subject to a powerful diurnal thermal and radiometric cycle not experienced by deep-space astronomy. The Horizon proposal was a bare-bones design for a lightweight large-aperture, active optical system that is a practical blend of science requirements, emerging technologies, budget constraints, launch vehicle considerations, orbital mechanics, optical hardware, phase-determination algorithms, communication strategy, computational burdens, and first-rate cooperation among earth and space scientists, engineers and managers

Approximate analytic method for high-apogee twelve-hour orbits of artificial Earth's satellites

NASA Astrophysics Data System (ADS)

Vashkovyaka, M. A.; Zaslavskii, G. S.

2016-09-01

We propose an approach to the study of the evolution of high-apogee twelve-hour orbits of artificial Earth's satellites. We describe parameters of the motion model used for the artificial Earth's satellite such that the principal gravitational perturbations of the Moon and Sun, nonsphericity of the Earth, and perturbations from the light pressure force are approximately taken into account. To solve the system of averaged equations describing the evolution of the orbit parameters of an artificial satellite, we use both numeric and analytic methods. To select initial parameters of the twelve-hour orbit, we assume that the path of the satellite along the surface of the Earth is stable. Results obtained by the analytic method and by the numerical integration of the evolving system are compared. For intervals of several years, we obtain estimates of oscillation periods and amplitudes for orbital elements. To verify the results and estimate the precision of the method, we use the numerical integration of rigorous (not averaged) equations of motion of the artificial satellite: they take into account forces acting on the satellite substantially more completely and precisely. The described method can be applied not only to the investigation of orbit evolutions of artificial satellites of the Earth; it can be applied to the investigation of the orbit evolution for other planets of the Solar system provided that the corresponding research problem will arise in the future and the considered special class of resonance orbits of satellites will be used for that purpose.

Clementine Images of Earth and Moon

NASA Technical Reports Server (NTRS)

1997-01-01

During its flight and lunar orbit, the Clementine spacecraft returned images of the planet Earth and the Moon. This collection of UVVIS camera Clementine images shows the Earth from the Moon and 3 images of the Earth.

The image on the left shows the Earth as seen across the lunar north pole; the large crater in the foreground is Plaskett. The Earth actually appeared about twice as far above the lunar horizon as shown. The top right image shows the Earth as viewed by the UVVIS camera while Clementine was in transit to the Moon; swirling white cloud patterns indicate storms. The two views of southeastern Africa were acquired by the UVVIS camera while Clementine was in low Earth orbit early in the mission

Application of single crystal superalloys for Earth-to-orbit propulsion systems

NASA Technical Reports Server (NTRS)

Dreshfield, R. L.; Parr, R. A.

1987-01-01

Single crystal superalloys were first identified as potentially useful engineering materials for aircraft gas turbine engines in the mid-1960's. Although they were not introduced into service as turbine blades in commercial aircraft engines until the early 1980's, they have subsequently accumulated tens of millions of flight hours in revenue producing service. The space shuttle main engine (SSME) and potential advanced earth-to-orbit propulsion systems impose severe conditions on turbopump turbine blades which for some potential failure modes are more severe than in aircraft gas turbines. Research activities which are directed at evaluating the potential for single crystal superalloys for application as turbopump turbine blades in the SSME and advanced rocket engines are discussed. The mechanical properties of these alloys are summarized and the effects of hydrogen are noted. The use of high gradient directional solidification and hot isostatic pressing to improve fatigue properties is also addressed.

Astrometric detectability of systems with unseen companions: effects of the Earth orbital motion

NASA Astrophysics Data System (ADS)

Butkevich, Alexey G.

2018-06-01

The astrometric detection of an unseen companion is based on an analysis of the apparent motion of its host star around the system's barycentre. Systems with an orbital period close to 1 yr may escape detection if the orbital motion of their host stars is observationally indistinguishable from the effects of parallax. Additionally, an astrometric solution may produce a biased parallax estimation for such systems. We examine the effects of the orbital motion of the Earth on astrometric detectability in terms of a correlation between the Earth's orbital position and the position of the star relative to its system barycentre. The χ2 statistic for parallax estimation is calculated analytically, leading to expressions that relate the decrease in detectability and accompanying parallax bias to the position correlation function. The impact of the Earth's motion critically depends on the exoplanet's orbital period, diminishing rapidly as the period deviates from 1 yr. Selection effects against 1-yr-period systems is, therefore, expected. Statistical estimation shows that the corresponding loss of sensitivity results in a typical 10 per cent increase in the detection threshold. Consideration of eccentric orbits shows that the Earth's motion has no effect on detectability for e≳ 0.5. The dependence of the detectability on other parameters, such as orbital phases and inclination of the orbital plane to the ecliptic, are smooth and monotonic because they are described by simple trigonometric functions.

First In-Orbit Experience of TerraSAR-X Flight Dynamics Operations

NASA Technical Reports Server (NTRS)

Kahle, R.; Kazeminejad, B.; Kirschner, M.; Yoon, Y.; Kiehling, R.; D'Amico, S.

2007-01-01

TerraSAR-X is an advanced synthetic aperture radar satellite system for scientific and commercial applications that is realized in a public-private partnership between the German Aerospace Center (DLR) and the Astrium GmbH. TerraSAR-X was launched at June 15, 2007 on top of a Russian DNEPR-1 rocket into a 514 km sun-synchronous dusk-dawn orbit with an 11-day repeat cycle and will be operated for a period of at least 5 years during which it will provide high resolution SAR-data in the X-band. Due to the objectives of the interferometric campaigns the satellite has to comply to tight orbit control requirements, which are formulated in the form of a 250 m toroidal tube around a pre-flight determined reference trajectory (see [1] for details). The acquisition of the reference orbit was one of the main and key activities during the Launch and Early Orbit Phase (LEOP) and had to compensate for both injection errors and spacecraft safe mode attitude control thruster activities. The paper summarizes the activities of GSOC flight dynamics team during both LEOP and early Commissioning Phase, where the main tasks have been 1) the first-acquisition support via angle-tracking and GPS-based orbit determination, 2) maneuver planning for target orbit acquisition and maintenance, and 3) precise orbit and attitude determination for SAR processing support. Furthermore, a presentation on the achieved results and encountered problems will be addressed.

Orion Exploration Flight Test Post-Flight Inspection and Analysis

NASA Technical Reports Server (NTRS)

Miller, J. E.; Berger, E. L.; Bohl, W. E.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.; Enriquez, P. A.; Garcia, M. A.; Hyde, J. L.; Oliveras, O. M.

2017-01-01

The multipurpose crew vehicle, Orion, is being designed and built for NASA to handle the rigors of crew launch, sustainment and return from scientific missions beyond Earth orbit. In this role, the Orion vehicle is meant to operate in the space environments like the naturally occurring meteoroid and the artificial orbital debris environments (MMOD) with successful atmospheric reentry at the conclusion of the flight. As a result, Orion's reentry module uses durable porous, ceramic tiles on almost thirty square meters of exposed surfaces to accomplish both of these functions. These durable, non-ablative surfaces maintain their surface profile through atmospheric reentry; thus, they preserve any surface imperfections that occur prior to atmospheric reentry. Furthermore, Orion's launch abort system includes a shroud that protects the thermal protection system while awaiting launch and during ascent. The combination of these design features and a careful pre-flight inspection to identify any manufacturing imperfections results in a high confidence that damage to the thermal protection system identified post-flight is due to the in-flight solid particle environments. These favorable design features of Orion along with the unique flight profile of the first exploration flight test of Orion (EFT-1) have yielded solid particle environment measurements that have never been obtained before this flight.

Accessible Near-Earth Objects (NEOs)

NASA Technical Reports Server (NTRS)

Barbee, Brent W.

2015-01-01

Near Earth Objects (NEOs) are asteroids and comets whose orbits are in close proximity to Earth's orbit; specifically, they have perihelia less than 1.3 astronomical units. NEOs particularly near Earth asteroids (NEAs) are identified as potential destinations for future human exploration missions. In this presentation I provide an overview of the current state of knowledge regarding the astrodynamical accessibility of NEAs according to NASA's Near Earth Object Human Space Flight Accessible Targets Study (NHATS). I also investigate the extremes of NEA accessibility using case studies and illuminate the fact that a space-based survey for NEOs is essential to expanding the set of known accessible NEAs for future human exploration missions.

Code-Name: Spider, Flight of Apollo 9.

ERIC Educational Resources Information Center

National Aeronautics and Space Administration, Washington, DC.

Apollo 9, an earth orbiting mission during which the Lunar Module was first tested in space flight in preparation for the eventual moon landing missions, is the subject of this pamphlet. Many color photographs and diagrams of the Lunar Module and flight activities are included with a brief description of the mission. (PR)

A Sub-Orbital Platform for Flight Tests of Small Space Capsules

NASA Astrophysics Data System (ADS)

Pereira, P. Moraes A. L., Jr.; Silva, C. R.; Villas Bôas, D. J.; Corrêa, F., Jr.; Miyoshi, J. H.; Loures da Costa, L. E.

2002-01-01

In the development of a small recoverable space capsule, flight tests using sub-orbital rockets are considered. For this test series, a platform for aerodynamic and thermal measurements as also for qualification tests of onboard sub-systems and equipment was specified and is actually under development. This platform, known as SARA Suborbital, is specified to withstand a sub-orbital flight with the high performance sounding rocket VS40 and to be recovered at the sea. To perform the testing program, a flight trajectory with adequate aeroballistic parameters, as for instance high velocities in dense atmosphere and average re-entry velocity, is considered. The testing program includes measurements of aerodynamic pressures and thermal characteristics, three- axis acceleration, acoustic pressure level inside the platform and vibration environment. Beside this, tests to characterise the performance of the data acquisition and transmission system, the micro-gravity environment and to qualify the recovery system will be carried out. During the return flight, the dynamics of parachutes deployment and platform water impact, as also rescue procedures will also be observed. The present article shows the concept of the platform, describes in detail the experiments, and concludes with a discussion on the flight trajectory and recovery procedure.

Crewmembers in the aft flight deck.

NASA Image and Video Library

1992-12-09

STS053-01-034 (2-9 Dec 1992) --- From the Space Shuttle Discovery's aft flight deck, astronaut Guion S. Bluford, mission specialist, uses a handheld 70mm Hasselblad to photograph a point on Earth. Bluford was joined by four other NASA astronauts for the eight-day mission in Earth-orbit, dedicated to the Department of Defense (DOD).

Effects of Low Earth Orbit on Docking Seal Materials

NASA Technical Reports Server (NTRS)

Imka, Emily C.; Asmar, Olivia C.; deGroh, Henry C., III; Banks, Bruce A.

2014-01-01

Spacecraft docking seals are typically made of silicone elastomers. When such seals are exposed to low Earth orbit (LEO) conditions, they can suffer damage from ultraviolet (UV) radiation and atomic oxygen (AO, or monoatomic oxygen, the predominant oxygen species in LEO). An experiment flew on the International Space Station (ISS) to measure the effects of LEO on seal materials S0383-70 and ELA-SA-401 and various mating counterface materials which included anodized aluminum. Samples flown in different orientations received different amounts of UV and AO. The hypotheses were that most of the damage would be from UV, and 10 days or more of exposure in LEO would badly damage the seals. Eighteen seals were exposed for 543 days in ram (windward), zenith (away from Earth), or wake (leeward) orientations, and 15 control samples (not flown) provided undamaged baseline leakage. To determine post-flight leak rates, each of the 33 seals were placed in an O-ring groove of a leak test fixture and pressure tested over time. Resistance temperature detectors (RTDs), pressure transducers, and LabVIEW (National Instruments) programs were used to measure and analyze the temperature and pressure and calculate leakage. Average leakage of control samples was 2.6 x 10(exp -7) lbs/day. LEO exposure did not considerably damage ELA-SA-401. The S0383-70 flight samples leaked at least 10 times more than ELA-SA-401 in all cases except one, demonstrating that ELA-SA-401 may be a more suitable sealing material in LEO. AO caused greater damage than UV; samples in ram orientation (receiving an AO fluence of 4.3 x 10(exp 21) atoms/(sq cm) and in wake (2.9x 10(exp 20) atoms/(sq cm)) leaked more than those in zenith orientation (1.58 x 10(exp 20) atoms/(sq cm)), whereas variations in UV exposure did not seem to affect the samples. Exposure to LEO did less damage to the seals than hypothesized, and the data did not support the conjecture that UV causes more damage than AO.

Permanent Habitats in Earth-Sol/Mars-Sol Orbit Positions

NASA Astrophysics Data System (ADS)

Greenspon, J.

Project Outpost is a manned Earth-Sol/Mars-Sol platform that enables permanent occupation in deep space. In order to develop the program elements for this complex mission, Project Outpost will rely primarily on existing/nearterm technology and hardware for the construction of its components. For the purposes of this study, four mission requirements are considered: 1. Outpost - Man's 1st purpose-produced effort of space engineering, in which astructure is developed/constructed in an environment completely alien to currentpractices for EVA guidelines. 2. Newton - a concept study developed at StarGate Research, for the development ofa modified Hohmann personnel orbital transport operating between Earth andMars. Newton would serve as the primary crew delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization. 3. Cruis - a concept study developed at StarGate Research, for the development of amodified Hohmann cargo orbital transport operating between Earth and Mars.Cruis would serve as the primary equipment delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization, and 4. Ares/Diana - a more conventional space platform configuration for Lunar andMars orbit is included as a construction baseline. The operations of these assetsare supported, and used for the support, of the outpost. Outpost would be constructed over a 27-year period of launch opportunities into Earth-Sol or Mars-Sol Lagrange orbit (E-S/M-S L1, 4 or 5). The outpost consists of an operations core with a self-contained power generation ability, a docking and maintenance structure, a Scientific Research complex and a Habitation Section. After achieving initial activation, the core will provide the support and energy required to operate the outpost in a 365

In-flight testing of the space shuttle orbiter thermal control system

NASA Technical Reports Server (NTRS)

Taylor, J. T.

1985-01-01

In-flight thermal control system testing of a complex manned spacecraft such as the space shuttle orbiter and the considerations attendant to the definition of the tests are described. Design concerns, design mission requirements, flight test objectives, crew vehicle and mission risk considerations, instrumentation, data requirements, and real-time mission monitoring are discussed. An overview of the tests results is presented.

Earth Orbital Science, Space in the Seventies.

ERIC Educational Resources Information Center

Corliss, William R.

This publication is part of the "Space in the Seventies" series and reviews the National Aeronautics and Space Administration's (NASA) earth orbital scientific research programs in progress and those to be pursued in the coming decade. Research in space physics is described in Part One in these areas: interplanetary monitoring platforms, small…

Apollo guidance, navigation and control: Guidance system operations plan for manned CM earth orbital and lunar missions using Program COLOSSUS 3. Section 3: Digital autopilots (revision 14)

NASA Technical Reports Server (NTRS)

1972-01-01

Digital autopilots for the manned command module earth orbital and lunar missions using program COLOSSUS 3 are discussed. Subjects presented are: (1) reaction control system digital autopilot, (2) thrust vector control autopilot, (3) entry autopilot and mission control programs, (4) takeover of Saturn steering, and (5) coasting flight attitude maneuver routine.

On the lunar node resonance of the orbital plane evolution of the Earth's satellite orbits

NASA Astrophysics Data System (ADS)

Zhu, Ting-Lei

2018-06-01

This paper aims to investigate the effects of lunar node resonance on the circular medium Earth orbits (MEO). The dynamical model is established in classical Hamiltonian systems with the application of Lie transform to remove the non-resonant terms. Resonant condition, stability and phase structures are studied. The lunar node resonance occurs when the secular changing rates of the orbital node (with respect to the equator) and the lunar node (with respect to the ecliptic) form a simple integer ratio. The resonant conditions are satisfied for both inclined and equatorial orbits. The orbital plane would have long period (with typical timescales of several centuries) fluctuation due to the resonance.

Near-Earth Asteroids: Destinations for Human Exploration

NASA Technical Reports Server (NTRS)

Barbee, Brent W.

2014-01-01

The Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) is a system that monitors the near-Earth asteroid (NEA) population to identify NEAs whose orbital characteristics may make them potential destinations for future round-trip human space flight missions. To accomplish this monitoring, Brent Barbee (GSFC) developed and automated a system that applies specialized trajectory processing to the orbits of newly discovered NEAs, and those for which we have updated orbit knowledge, obtained from the JPL Small Bodies Database (SBDB). This automated process executes daily and the results are distributed to the general public and the astronomy community. This aids in prioritizing telescope radar time allocations for obtaining crucial follow-up observations of highly accessible NEAs during the critical, because it is often fleeting, time period surrounding the time at which the NEAs are initially discovered.

Medium Earth Orbits: Is There a Need for a Third Protected Region?

NASA Technical Reports Server (NTRS)

Johnson, Nicholas L.

2010-01-01

The Inter-Agency Space Debris Coordination Committee (IADC) and the United Nations have adopted the concept of near-Earth regions which should be afforded protection from the accumulation of orbital debris. These regions are low Earth orbit (LEO), which extends up to 2000 km altitude, and geosynchronous orbit (GEO), which includes the volume of space encompassed by 35,786 km +/- 200 km in altitude and +/- 15 degrees in inclination. The region between LEO and GEO is commonly referred to as Medium Earth Orbit (MEO). Although historically a small minority of spacecraft have operated in MEO, the number of such satellites residing in or routinely transiting the zone is increasing. The question thus arises: should MEO be considered an orbital debris protected region? This paper first reviews the characteristics of space systems now utilizing MEO, as well as those anticipated to join them in the near future. MEO is then contrasted with LEO and GEO, both physically and pragmatically. Recommended orbital debris mitigation guidelines for MEO space vehicles are highlighted, and the challenges of spacecraft and launch vehicle stage disposal are recognized. Note is also made of the principal tenets of the United Nations Outer Space Treaty and of recent trends toward de facto partitioning of MEO. Finally, the efficacy and practicality of establishing MEO as a new protected region with regard to orbital debris is addressed.

Advantages of High vs. Low Earth Orbit for SIRTF

NASA Technical Reports Server (NTRS)

Eisenhardt, Peter; Werner, Michael W.

1989-01-01

While the subject of this workshop, which we will refer to as ET (for Enlightenment Telescope), is a dazzling successor to the Hubble Space Telescope, its location is unlikely to be the Low Earth Orbit (LEO) used by HST. Locations suggested for ET include High Earth Orbit (HEO) and the moon. The first space telescope to occupy HEO will be the liquid helium cooled Space Infrared Telescope Facility (SIRTF). The selection of HEO for SIRTF was the outcome of a recent study led by the Ames Research Center which showed significant advantages for SIRTF in HEO vs. LEO. This article summarizes the main results of that study. We begin with a review of SIRTF's rationale and requirements, in part because the IR capabilities and low temperature proposed for ET make it something of a successor to SIRTF as well as to HST. We conclude with some comments about another possible location for both SIRTF and ET, the Earth-Sun L2 Lagrangian point.

Trojan Asteroid Shares Orbit with Earth Artist Animation

NASA Image and Video Library

2011-07-27

This artist concept illustrates the first known Earth Trojan asteroid, discovered by NEOWISE, the asteroid-hunting portion of NASA WISE mission. The asteroid is shown in gray and its extreme orbit is shown in green. Objects are not drawn to scale.

MSR ESA Earth Return Orbiter Mission Design Trades

NASA Astrophysics Data System (ADS)

Sanchez Perez, J. M.; Varga, G. I.; Huesing, J.; Beyer, F.

2018-04-01

The paper describes the work performed at ESOC in support of the Mars Sample Return ESA Earth Return Orbiter definition studies by exploring the trajectory optimization and mission design trade spaces of Mars return missions using electric and chemical propulsion.

The Space Launch System -The Biggest, Most Capable Rocket Ever Built, for Entirely New Human Exploration Missions Beyond Earth's Orbit

NASA Technical Reports Server (NTRS)

Shivers, C. Herb

2012-01-01

NASA is developing the Space Launch System -- an advanced heavy-lift launch vehicle that will provide an entirely new capability for human exploration beyond Earth's orbit. The Space Launch System will provide a safe, affordable and sustainable means of reaching beyond our current limits and opening up new discoveries from the unique vantage point of space. The first developmental flight, or mission, is targeted for the end of 2017. The Space Launch System, or SLS, will be designed to carry the Orion Multi-Purpose Crew Vehicle, as well as important cargo, equipment and science experiments to Earth's orbit and destinations beyond. Additionally, the SLS will serve as a backup for commercial and international partner transportation services to the International Space Station. The SLS rocket will incorporate technological investments from the Space Shuttle Program and the Constellation Program in order to take advantage of proven hardware and cutting-edge tooling and manufacturing technology that will significantly reduce development and operations costs. The rocket will use a liquid hydrogen and liquid oxygen propulsion system, which will include the RS-25D/E from the Space Shuttle Program for the core stage and the J-2X engine for the upper stage. SLS will also use solid rocket boosters for the initial development flights, while follow-on boosters will be competed based on performance requirements and affordability considerations.

Why Atens Enjoy Enhanced Accessibility for Human Space Flight

NASA Technical Reports Server (NTRS)

Barbee, Brent W.; Adamo, Daniel R.

2011-01-01

Near-Earth objects can be grouped into multiple orbit classifications, among them being the Aten group, whose members have orbits crossing Earth's with semi-major axes less than 1 astronomical unit. Atens comprise well under 10% of known near-Earth objects. This is in dramatic contrast to results from recent human space flight near-Earth object accessibility studies, where the most favorable known destinations are typically almost 50% Atens. Geocentric dynamics explain this enhanced Aten accessibility and lead to an understanding of where the most accessible near-Earth objects reside. Without a comprehensive space-based survey, however, highly accessible Atens will remain largely unknown.

Clementine Images of Earth and Moon

NASA Image and Video Library

1999-06-12

During its flight and lunar orbit, NASA’s Clementine spacecraft returned images of the planet Earth and the Moon. This collection of UVVIS camera Clementine images shows the Earth from the Moon and 3 images of the Earth. The image on the left shows the Earth as seen across the lunar north pole; the large crater in the foreground is Plaskett. The Earth actually appeared about twice as far above the lunar horizon as shown. The top right image shows the Earth as viewed by the UVVIS camera while Clementine was in transit to the Moon; swirling white cloud patterns indicate storms. The two views of southeastern Africa were acquired by the UVVIS camera while Clementine was in low Earth orbit early in the mission. http://photojournal.jpl.nasa.gov/catalog/PIA00432

Seasat. Volume 2: Flight systems

NASA Technical Reports Server (NTRS)

Pounder, E. (Editor)

1980-01-01

Flight systems used in the Seasat Project are described. Included are (1) launch operation; (2) satellite performance after launch; (3) sensors that collected data; and (4) the launch vehicle that placed the satellite into Earth orbit. Techniques for sensor management are explained.

Auroral x-ray imaging from high- and low-Earth orbit

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

McKenzie, D.L.; Gorney, D.J.; Imhof, W.L.

Observations of bremsstrahlung x rays emitted by energetic electrons impacting the Earth's atmosphere can be used for remotely sensing the morphology, intensity, and energy spectra of electron precipitation from the magnetosphere. The utility of the technique is derived from the broad energy range of observable x rays (2 to > 100 KeV), the simple emission process, the large x-ray mean free path in the atmosphere, and negligible background. Two auroral x-ray imagers, developed for future spaceflights, are discussed. The Polar Ionospheric X-Ray Imaging Experiment is scheduled for launch on the NASA International Solar-Terrestrial Physics/Global Geospace Science program POLAR satellite inmore » 1994. The POLAR orbit, with an apogee and perigee of 9 and 1.8 R[sub e] (Earth radii), respectively, affords the opportunity to image the aurora from a high altitude above the north pole continuously for several hours. The Magnetospheric Atmospheric X-Ray Imaging Experiment (MAXIE) was launched aboard the NOAA-I satellite on August 8, 1993. The 800-km polar orbit passes over both the northern and southern auroral zones every 101 min. MAXIE will be capable of obtaining multiple images of the same auroral region during a single satellite orbit. The experimental approaches used to exploit these very different orbits for remote sensing of the Earth's auroral zones are emphasized.« less

Density variations of meteor flux along the Earth's orbit

NASA Technical Reports Server (NTRS)

Svetashkova, N. T.

1987-01-01

No model of distribution of meteor substance is known to explain the observed diurnal and annual variations of meteor rates, if that distribution is assumed to be constant during the year. Differences between the results of observations and the prediction of diurnal variation rates leads to the conclusion that the density of the orbits of meteor bodies changes with the motion of the Earth along its orbit. The distributions of the flux density over the celestial sphere are obtained by the method described previously by Svetashkova, 1984. The results indicate that the known seasonal and latitudinal variations of atmospheric conditions does not appear to significantly affect the value of the mean flux density of meteor bodies and the matter influx onto the Earth.

Multi-sun-synchronous (MSS) orbits for earth observation

NASA Astrophysics Data System (ADS)

Ulivieri, Carlo; Anselmo, Luciano

1992-08-01

A case study is outlined for a remote-sensing mission at low and middle latitudes based on multi-sun-synchronous (MSS) orbits. The scenario involves the use of small payloads in low-earth posigrade orbits that would overfly the Mediterranean region. A 600-kg spacecraft is considered in an orbit that is 571 km in altitude and at an inclination of 42.5 deg. The orbit is analyzed in terms of mission characteristics, and two years of operation is shown to be feasible with a fuel-consumption rate of less than three kg/yr of hydrazine. The mission could be based on the use of a Scout solid-propellant rockets into an MSS orbit, and only a limited number of ground stations are required for good data collection. A remote-sensing mission at low/middle latitudes is shown to be efficient in terms of both revisit frequency, fuel consumption, and data acquisition.

UV SURFACE ENVIRONMENT OF EARTH-LIKE PLANETS ORBITING FGKM STARS THROUGH GEOLOGICAL EVOLUTION

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

Rugheimer, S.; Sasselov, D.; Segura, A.

2015-06-10

The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early-Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present-day levels at 2.0 Gyr ago, 0.8 Gyr ago, and modern Earth. In addition to calculating the UVmore » flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth–Sun levels. A pre-biotic Earth orbiting GJ 581 (M3.5 V) receives 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments and for pre-biotic chemistry and early life evolution experiments.« less

Preliminary Design Considerations for Access and Operations in Earth-Moon L1/L2 Orbits

NASA Technical Reports Server (NTRS)

Folta, David C.; Pavlak, Thomas A.; Haapala, Amanda F.; Howell, Kathleen C.

2013-01-01

Within the context of manned spaceflight activities, Earth-Moon libration point orbits could support lunar surface operations and serve as staging areas for future missions to near-Earth asteroids and Mars. This investigation examines preliminary design considerations including Earth-Moon L1/L2 libration point orbit selection, transfers, and stationkeeping costs associated with maintaining a spacecraft in the vicinity of L1 or L2 for a specified duration. Existing tools in multi-body trajectory design, dynamical systems theory, and orbit maintenance are leveraged in this analysis to explore end-to-end concepts for manned missions to Earth-Moon libration points.

Earth to Orbit Beamed Energy Experiment

NASA Technical Reports Server (NTRS)

Johnson, Les; Montgomery, Edward E.

2017-01-01

As a means of primary propulsion, beamed energy propulsion offers the benefit of offloading much of the propulsion system mass from the vehicle, increasing its potential performance and freeing it from the constraints of the rocket equation. For interstellar missions, beamed energy propulsion is arguably the most viable in the near- to mid-term. A near-term demonstration showing the feasibility of beamed energy propulsion is necessary and, fortunately, feasible using existing technologies. Key enabling technologies are large area, low mass spacecraft and efficient and safe high power laser systems capable of long distance propagation. NASA is currently developing the spacecraft technology through the Near Earth Asteroid Scout solar sail mission and has signed agreements with the Planetary Society to study the feasibility of precursor laser propulsion experiments using their LightSail-2 solar sail spacecraft. The capabilities of Space Situational Awareness assets and the advanced analytical tools available for fine resolution orbit determination now make it possible to investigate the practicalities of an Earth-to-orbit Beamed Energy eXperiment (EBEX) - a demonstration at delivered power levels that only illuminate a spacecraft without causing damage to it. The degree to which this can be expected to produce a measurable change in the orbit of a low ballistic coefficient spacecraft is investigated. Key system characteristics and estimated performance are derived for a near term mission opportunity involving the LightSail-2 spacecraft and laser power levels modest in comparison to those proposed previously. While the technology demonstrated by such an experiment is not sufficient to enable an interstellar precursor mission, if approved, then it would be the next step toward that goal.

ARTEMIS: The First Mission to the Lunar Libration Orbits

NASA Technical Reports Server (NTRS)

Woodward, Mark; Folta, David; Woodfork, Dennis

2009-01-01

The ARTEMIS mission will be the first to navigate to and perform stationkeeping operations around the Earth-Moon L1 and L2 Lagrangian points. The NASA Goddard Space Flight Center (GSFC) has previous mission experience flying in the Sun-Earth L1 (SOHO, ACE, WIND, ISEE-3) and L2 regimes (WMAP) and have maintained these spacecraft in libration point orbits by performing regular orbit stationkeeping maneuvers. The ARTEMIS mission will build on these experiences, but stationkeeping in Earth-Moon libration orbits presents new challenges since the libration point orbit period is on the order of two weeks rather than six months. As a result, stationkeeping maneuvers to maintain the Lissajous orbit will need to be performed frequently, and the orbit determination solutions between maneuvers will need to be quite accurate. The ARTEMIS mission is a collaborative effort between NASA GSFC, the University of California at Berkeley (UCB), and the Jet Propulsion Laboratory (JPL). The ARTEMIS mission is part of the THEMIS extended mission. ARTEMIS comprises two of the five THEMIS spacecraft that will be maneuvered from near-Earth orbits into lunar libration orbits using a sequence of designed orbital maneuvers and Moon & Earth gravity assists. In July 2009, a series of orbit-raising maneuvers began the proper orbit phasing of the two spacecraft for the first lunar flybys. Over subsequent months, additional propulsive maneuvers and gravity assists will be performed to move each spacecraft though the Sun-Earth weak stability regions and eventually into Earth-Moon libration point orbits. We will present the overall orbit designs for the two ARTEMIS spacecraft and provide analysis results of the 3/4-body dynamics, and the sensitivities of the trajectory design to both · maneuver errors and orbit determination errors. We will present results from the. initial orbit-raising maneuvers.

Lissajous Orbit Control for the Deep Space Climate Observatory Sun-Earth L1 Libration Point Mission

NASA Technical Reports Server (NTRS)

Roberts, Craig; Case, Sarah; Reagoso, John

2015-01-01

DSCOVR Lissajous Orbit sized such that orbit track never extends beyond 15 degrees from Earth-Sun line (as seen from Earth). Requiring delta-V maneuvers, control orbit to obey a Solar Exclusion Zone (SEZ) cone of half-angle 4 degrees about the Earth-Sun line. Spacecraft should never be less than 4 degrees from solar center as seen from Earth. Following Lissajous Orbit Insertion (LOI), DSCOVR should be in an opening phase that just skirts the 4-degree SEZ. Maximizes time to the point where a closing Lissajous will require avoidance maneuvers to keep it out of the SEZ. Station keeping maneuvers should take no more than 15 minutes.

General view of the flight deck of the Orbiter Discovery ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

General view of the flight deck of the Orbiter Discovery looking from a low angle up and aft from approximately behind the commander's station. In the view you can see the overhead aft observation windows, the payload operations work area and in this view the payload bay observation windows have protective covers on them. This view was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

Near Earth asteroid orbit perturbation and fragmentation

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.; Harris, Alan W.

1992-01-01

Collisions by near earth asteroids or the nuclei of comets pose varying levels of threat to man. A relatively small object, approximately 100 meter diameter, which might be found on an impact trajectory with a populated region of the Earth, could potentially be diverted from an Earth impacting trajectory by mass driver rocket systems. For larger bodies, such systems would appear to be beyond current technology. For any size object, nuclear explosions appear to be more efficient, using either the prompt blow-off from neutron radiation, the impulse from ejecta of near-surface explosion for deflection, or as a fragmenting charge. Practical deflections of bodies with diameters of 0.1, 1, and 10 km require interception, years to decades prior to earth encounter, with explosions a few kilotons, megatons, or gigatons, respectively, of equivalent TNT energy to achieve orbital velocity changes or destruction to a level where fragments are dispersed to harmless spatial densities.

Free Space Laser Communication Experiments from Earth to the Lunar Reconnaissance Orbiter in Lunar Orbit

NASA Technical Reports Server (NTRS)

Sun, Xiaoli; Skillman, David R.; Hoffman, Evan D.; Mao, Dandan; McGarry, Jan F.; Zellar, Ronald S.; Fong, Wai H; Krainak, Michael A.; Neumann, Gregory A.; Smith, David E.

2013-01-01

Laser communication and ranging experiments were successfully conducted from the satellite laser ranging (SLR) station at NASA Goddard Space Flight Center (GSFC) to the Lunar Reconnaissance Orbiter (LRO) in lunar orbit. The experiments used 4096-ary pulse position modulation (PPM) for the laser pulses during one-way LRO Laser Ranging (LR) operations. Reed-Solomon forward error correction codes were used to correct the PPM symbol errors due to atmosphere turbulence and pointing jitter. The signal fading was measured and the results were compared to the model.

From Earth to orbit. [assessment of transportation options

NASA Technical Reports Server (NTRS)

Gavin, Joseph G., Jr.; Blond, Edmund; Brill, Yvonne C.; Budiansky, Bernard; Cooper, Robert S.; Demisch, Wolfgang H.; Hawk, Clark W.; Kerrebrock, Jack L.; Lichtenberg, Byron K.; Mager, Arthur

1992-01-01

Within this document, the National Research Council (NRC) assesses the requirements, benefits, technological feasibility, and roles of Earth-to-orbit transportation options that could be developed in support of the national space program. Among the topics covered are launch vehicles and infrastructure, propulsion, and technology.

The calibration and flight test performance of the space shuttle orbiter air data system

NASA Technical Reports Server (NTRS)

Dean, A. S.; Mena, A. L.

1983-01-01

The Space Shuttle air data system (ADS) is used by the guidance, navigation and control system (GN&C) to guide the vehicle to a safe landing. In addition, postflight aerodynamic analysis requires a precise knowledge of flight conditions. Since the orbiter is essentially an unpowered vehicle, the conventional methods of obtaining the ADS calibration were not available; therefore, the calibration was derived using a unique and extensive wind tunnel test program. This test program included subsonic tests with a 0.36-scale orbiter model, transonic and supersonic tests with a smaller 0.2-scale model, and numerous ADS probe-alone tests. The wind tunnel calibration was further refined with subsonic results from the approach and landing test (ALT) program, thus producing the ADS calibration for the orbital flight test (OFT) program. The calibration of the Space Shuttle ADS and its performance during flight are discussed in this paper. A brief description of the system is followed by a discussion of the calibration methodology, and then by a review of the wind tunnel and flight test programs. Finally, the flight results are presented, including an evaluation of the system performance for on-board systems use and a description of the calibration refinements developed to provide the best possible air data for postflight analysis work.

Auxiliary propulsion technology for advanced Earth-to-orbit vehicles

NASA Technical Reports Server (NTRS)

Schneider, Steven J.

1987-01-01

The payload which can be delivered to orbit by advanced Earth-to-Orbit vehicles is significantly increased by advanced subsystem technology. Any weight which can be saved by advanced subsystem design can be converted to payload at Main Engine Cut Off (MECO) given the same launch vehicle performance. The auxiliary propulsion subsystem and the impetus for the current hydrogen/oxygen technology program is examined. A review of the auxiliary propulsion requirements of advanced Earth-to-Orbit (ETO) vehicles and their proposed missions is given first. Then the performance benefits of hydrogen/oxygen auxiliary propulsion are illustrated using current shuttle data. The proposed auxiliary propulsion subsystem implementation includes liquid hydrogen/liquid oxygen (LH2/LO2) primary Reaction Control System (RCS) engines and gaseous hydrogen/gaseous oxygen (GH2/GO2) vernier RCS engines. A distribution system for the liquid cryogens to the engines is outlined. The possibility of providing one dual-phase engine that can operate on either liquid or gaseous propellants is being explored, as well as the simultaneous firing of redundant primary RCS thrusters to provide Orbital Maneuvering System (OMS) level impulse. Scavenging of propellants from integral main engine tankage is proposed to utilize main engine tank residuals and to combine launch vehicle and subsystem reserves.

Thermal Orbital Environmental Parameter Study on the Propulsive Small Expendable Deployer System (ProSEDS) Using Earth Radiation Budget Experiment (ERBE) Data

NASA Technical Reports Server (NTRS)

Sharp, John R.; McConnaughey, Paul K. (Technical Monitor)

2002-01-01

The natural thermal environmental parameters used on the Space Station Program (SSP 30425) were generated by the Space Environmental Effects Branch at NASA's Marshall Space Flight Center (MSFC) utilizing extensive data from the Earth Radiation Budget Experiment (ERBE), a series of satellites which measured low earth orbit (LEO) albedo and outgoing long-wave radiation. Later, this temporal data was presented as a function of averaging times and orbital inclination for use by thermal engineers in NASA Technical Memorandum TM 4527. The data was not presented in a fashion readily usable by thermal engineering modeling tools and required knowledge of the thermal time constants and infrared versus solar spectrum sensitivity of the hardware being analyzed to be used properly. Another TM was recently issued as a guideline for utilizing these environments (NASA/TM-2001-211221) with more insight into the utilization by thermal analysts. This paper gives a top-level overview of the environmental parameters presented in the TM and a study of the effects of implementing these environments on an ongoing MSFC project, the Propulsive Small Expendable Deployer System (ProSEDS), compared to conventional orbital parameters that had been historically used.

Artist's concept of Skylab space station cluster in Earth's orbit

NASA Image and Video Library

1971-10-01

S71-52192 (1971) --- An artist's concept of the Skylab space station cluster in Earth's orbit. The cutaway view shows astronaut activity in the Orbital Workshop (OWS). The Skylab cluster is composed of the OWS, Airlock Module (AM), Multiple Docking Adapter (MDA), Apollo Telescope Mount (ATM), and the Command and Service Module (CSM). Photo credit: NASA

New method for estimating low-earth-orbit collision probabilities

NASA Technical Reports Server (NTRS)

Vedder, John D.; Tabor, Jill L.

1991-01-01

An unconventional but general method is described for estimating the probability of collision between an earth-orbiting spacecraft and orbital debris. This method uses a Monte Caralo simulation of the orbital motion of the target spacecraft and each discrete debris object to generate an empirical set of distances, each distance representing the separation between the spacecraft and the nearest debris object at random times. Using concepts from the asymptotic theory of extreme order statistics, an analytical density function is fitted to this set of minimum distances. From this function, it is possible to generate realistic collision estimates for the spacecraft.

Earth Science Microwave Remote Sensing at NASA's Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Kim, Edward; Busalacchi, Antonio J. (Technical Monitor)

2000-01-01

The Goddard Space Flight Center (GSFC) was established as NASA's first space flight center in 1959. Its 12,000 personnel are active in the Earth and space sciences, astronomy, space physics, tracking and communications. GSFC's mission is to expand our knowledge of the Earth and its environment, the solar system, and the universe through observations from space. The main Goddard campus is located in Greenbelt, Maryland, USA, just north of Washington, D.C. The Wallops Flight Facility (operational since 1945), located on the Atlantic coast of Virginia was consolidated with the Goddard Space Flight Center in 1982. Wallops is now NASA's principal facility for management and implementation of suborbital research programs, and supports a wide variety of airborne science missions as well. As the lead Center for NASA's Earth Science Enterprise (ESE)--a long-term, coordinated research effort to study the Earth as a global environmental system--GSFC scientists and engineers are involved in a wide range of Earth Science remote sensing activities. Their activities range from basic geoscience research to the development of instruments and technology for space missions, as well as the associated Calibration/Validation (Cal/Val) work. The shear breadth of work in these areas precludes an exhaustive description here. Rather, this article presents selected brief overviews of microwave-related Earth Science applications and the ground-based, airborne, and space instruments that are in service, under development, or otherwise significantly involving GSFC. Likewise, contributing authors are acknowledged for each section, but the results and projects they describe represent the cumulative efforts of many persons at GSFC as well as at collaborating institutions. For further information, readers are encouraged to consult the listed websites and references.

Low Earth Orbit satellite traffic simulator

NASA Technical Reports Server (NTRS)

Hoelzel, John

1995-01-01

This paper describes a significant tool for Low Earth Orbit (LEO) capacity analysis, needed to support marketing, economic, and design analysis, known as a Satellite Traffic Simulator (STS). LEO satellites typically use multiple beams to help achieve the desired communication capacity, but the traffic demand in these beams in usually not uniform. Simulations of dynamic, average, and peak expected demand per beam is a very critical part of the marketing, economic, and design analysis necessary to field a viable LEO system. An STS is described in this paper which can simulate voice, data and FAX traffic carried by LEO satellite beams and Earth Station Gateways. It is applicable world-wide for any LEO satellite constellations operating over any regions. For aeronautical applications to LEO satellites. the anticipates aeronautical traffic (Erlangs for each hour of the day to be simulated) is prepared for geographically defined 'area targets' (each major operational region for the respective aircraft), and used as input to the STS. The STS was designed by Constellations Communications Inc. (CCI) and E-Systems for usage in Brazil in accordance with an ESCA/INPE Statement Of Work, and developed by Analytical Graphics Inc. (AGI) to execute on top of its Satellite Tool Kit (STK) commercial software. The STS simulates constellations of LEO satellite orbits, with input of traffic intensity (Erlangs) for each hour of the day generated from area targets (such as Brazilian States). accumulated in custom LEO satellite beams, and then accumulated in Earth Station Gateways. The STS is a very general simulator which can accommodate: many forms of orbital element and Walker Constellation input; simple beams or any user defined custom beams; and any location of Gateways. The paper describes some of these features, including Manual Mode dynamic graphical display of communication links, to illustrate which Gateway links are accessible and which links are not, at each 'step' of the

Analysis of orbital configurations for geocenter determination with GPS and low-Earth orbiters

NASA Astrophysics Data System (ADS)

Kuang, Da; Bar-Sever, Yoaz; Haines, Bruce

2015-05-01

We use a series of simulated scenarios to characterize the observability of geocenter location with GPS tracking data. We examine in particular the improvement realized when a GPS receiver in low Earth orbit (LEO) augments the ground network. Various orbital configurations for the LEO are considered and the observability of geocenter location based on GPS tracking is compared to that based on satellite laser ranging (SLR). The distance between a satellite and a ground tracking-site is the primary measurement, and Earth rotation plays important role in determining the geocenter location. Compared to SLR, which directly and unambiguously measures this distance, terrestrial GPS observations provide a weaker (relative) measurement for geocenter location determination. The estimation of GPS transmitter and receiver clock errors, which is equivalent to double differencing four simultaneous range measurements, removes much of this absolute distance information. We show that when ground GPS tracking data are augmented with precise measurements from a GPS receiver onboard a LEO satellite, the sensitivity of the data to geocenter location increases by more than a factor of two for Z-component. The geometric diversity underlying the varying baselines between the LEO and ground stations promotes improved global observability, and renders the GPS technique comparable to SLR in terms of information content for geocenter location determination. We assess a variety of LEO orbital configurations, including the proposed orbit for the geodetic reference antenna in space mission concept. The results suggest that a retrograde LEO with altitude near 3,000 km is favorable for geocenter determination.

View of Atlantis Flight Deck Monitors

NASA Image and Video Library

2009-05-17

S125-E-009190 (17 May 2009) --- A computer monitor showing animation of an extravehicular activity (EVA) is visible in this image photographed by a STS-125 crewmember in a darkened flight deck on the Earth-orbiting Space Shuttle Atlantis.

Satellite laser ranging to low Earth orbiters: orbit and network validation

NASA Astrophysics Data System (ADS)

Arnold, Daniel; Montenbruck, Oliver; Hackel, Stefan; Sośnica, Krzysztof

2018-04-01

Satellite laser ranging (SLR) to low Earth orbiters (LEOs) provides optical distance measurements with mm-to-cm-level precision. SLR residuals, i.e., differences between measured and modeled ranges, serve as a common figure of merit for the quality assessment of orbits derived by radiometric tracking techniques. We discuss relevant processing standards for the modeling of SLR observations and highlight the importance of line-of-sight-dependent range corrections for the various types of laser retroreflector arrays. A 1-3 cm consistency of SLR observations and GPS-based precise orbits is demonstrated for a wide range of past and present LEO missions supported by the International Laser Ranging Service (ILRS). A parameter estimation approach is presented to investigate systematic orbit errors and it is shown that SLR validation of LEO satellites is not only able to detect radial but also along-track and cross-track offsets. SLR residual statistics clearly depend on the employed precise orbit determination technique (kinematic vs. reduced-dynamic, float vs. fixed ambiguities) but also reveal pronounced differences in the ILRS station performance. Using the residual-based parameter estimation approach, corrections to ILRS station coordinates, range biases, and timing offsets are derived. As a result, root-mean-square residuals of 5-10 mm have been achieved over a 1-year data arc in 2016 using observations from a subset of high-performance stations and ambiguity-fixed orbits of four LEO missions. As a final contribution, we demonstrate that SLR can not only validate single-satellite orbit solutions but also precise baseline solutions of formation flying missions such as GRACE, TanDEM-X, and Swarm.

Methodology and Results of the Near-Earth Object (NEO) Human Space Flight (HSF) Accessible Targets Study (NHATS)

NASA Technical Reports Server (NTRS)

Barbee, Brent; Mink, Ronald; Adamo, Daniel

2011-01-01

Near-Earth Asteroids (NEAs) have been identified by the current administration as potential destinations for human explorers during the mid-2020s. While the close proximity of these objects' orbits to Earth's orbit creates a risk of highly damaging or catastrophic impacts, it also makes some of these objects particularly accessible to spacecraft departing Earth, and this presents unique opportunities for solar system science and humanity's first ventures beyond cislunar space. Planning such ambitious missions first requires the selection of potentially accessible targets from the growing population of nearly 7,800 NEAs. To accomplish this, NASA is conducting the Near-Earth Object (NEO) Human Space Flight (HSF) Accessible Targets Study (NHATS). Phase I of the NHATS was executed during September of 2010, and Phase II was completed by early March of 2011. The study is ongoing because previously undetected NEAs are being discovered constantly, which has motivated an effort to automate the analysis algorithms in order to provide continuous monitoring of NEA accessibility. The NHATS analysis process consists of a trajectory filter and a minimum maximum estimated size criterion. The trajectory filter employs the method of embedded trajectory grids to compute all possible ballistic round-trip mission trajectories to every NEA in the Jet Propulsion Laboratory (JPL) Small-Body Database (SBDB) and stores all solutions that satisfy the trajectory filter criteria. An NEA must offer at least one qualifying trajectory solution to pass the trajectory filter. The Phase II NHATS filter criteria were purposely chosen to be highly inclusive, requiring Earth departure date between January 1st, 2015 and December 31st, 2040, total round-trip flight time <= 450 days, stay time at the NEA >= 8 days, Earth departure C(sub 3) energy <= 60 km(exp 2)/s(exp 2), total mission delta-v <= 12 km/s (including an Earth departure maneuver from a 400 km altitude circular parking orbit), and a maximum

Extravehicular activity at geosynchronous earth orbit

NASA Technical Reports Server (NTRS)

Shields, Nicholas, Jr.; Schulze, Arthur E.; Carr, Gerald P.; Pogue, William

1988-01-01

The basic contract to define the system requirements to support the Advanced Extravehicular Activity (EVA) has three phases: EVA in geosynchronous Earth orbit; EVA in lunar base operations; and EVA in manned Mars surface exploration. The three key areas to be addressed in each phase are: environmental/biomedical requirements; crew and mission requirements; and hardware requirements. The structure of the technical tasks closely follows the structure of the Advanced EVA studies for the Space Station completed in 1986.

Earth Observing-1 Advanced Land Imager: Imaging Performance On-Orbit

NASA Technical Reports Server (NTRS)

Hearn, D. R.

2002-01-01

This report analyzes the on-orbit imaging performance of the Advanced Land Imager (ALI) on the Earth Observing-1 satellite. The pre-flight calibrations are first summarized. The methods used to reconstruct and geometrically correct the image data from this push-broom sensor are described. The method used here does not refer to the position and attitude telemetry from the spacecraft. Rather, it is assumed that the image of the scene moves across the focal plane with a constant velocity, which can be ascertained from the image data itself. Next, an assortment of the images so reconstructed is presented. Color images sharpened with the 10-m panchromatic band data are shown, and the algorithm for producing them from the 30-m multispectral data is described. The approach taken for assessing spatial resolution is to compare the sharpness of features in the on-orbit image data with profiles predicted on the basis of the pre-flight calibrations. A large assortment of bridge profiles is analyzed, and very good fits to the predicted shapes are obtained. Lunar calibration scans are analyzed to examine the sharpness of the edge-spread function at the limb of the moon. The darkness of the space beyond the limb is better for this purpose than anything that could be simulated on the ground. From these scans, we find clear evidence of scattering in the optical system, as well as some weak ghost images. Scans of planets and stars are also analyzed. Stars are useful point sources of light at all wavelengths, and delineate the point-spread functions of the system. From a quarter-speed scan over the Pleiades, we find that the ALI can detect 6th magnitude stars. The quality of the reconstructed images verifies the capability of the ALI to produce Landsat-type multi spectral data. The signal-to-noise and panchromatic spatial resolution are considerably superior to those of the existing Landsat sensors. The spatial resolution is confirmed to be as good as it was designed to be.

Sun-Earth L1 Region Halo-To-Halo Orbit and Halo-To-LisaJous Orbit Transfers

NASA Technical Reports Server (NTRS)

Roberts, Craig E.; DeFazio, Robert

2004-01-01

Practical techniques for designing transfer trajectories between Libration Point Orbits (LPOs) are presented. Motivation for development of these techniques was provided by a hardware contingency experienced by the Solar Heliospheric Observatory (SOHO), a joint mission of the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA) orbiting the L1 point of the Sun-Earth system. A potential solution to the problem involved a transfer from SOHO s periodic halo orbit to a new LPO of substantially different dimensions. Assuming the SOHO halo orbit as the departure orbit, several practical LPO transfer techniques were developed to obtain new Lissajous or periodic halo orbits that satisfy mission requirements and constraints. While not implemented for the SOHO mission, practical LPO transfer techniques were devised that are generally applicable to current and future LPO missions.

Orion flight test previewed on This Week @NASA - November 7, 2014

NASA Image and Video Library

2014-11-07

A NASA media briefing on Nov. 6 at Kennedy Space Center highlighted the fully assembled Orion spacecraft and details of its first test flight, scheduled for Dec. 4. The 4 and-a-half hour flight, called Exploration Flight Test-1, will send Orion 3,600 miles from Earth on a two-orbit flight to confirm its critical systems are ready for the challenges of eventually sending astronauts on deep space missions to an asteroid and Mars. Also, Delta IV Heavy wet dress test, Next ISS crew trains, Space agency leaders support ISS, Curiosity confirms orbital data and more!

Two-stage earth-to-orbit vehicles with dual-fuel propulsion in the Orbiter

NASA Technical Reports Server (NTRS)

Martin, J. A.

1982-01-01

Earth-to-orbit vehicle studies of future replacements for the Space Shuttle are needed to guide technology development. Previous studies that have examined single-stage vehicles have shown advantages for dual-fuel propulsion. Previous two-stage system studies have assumed all-hydrogen fuel for the Orbiters. The present study examined dual-fuel Orbiters and found that the system dry mass could be reduced with this concept. The possibility of staging the booster at a staging velocity low enough to allow coast-back to the launch site is shown to be beneficial, particularly in combination with a dual-fuel Orbiter. An engine evaluation indicated the same ranking of engines as did a previous single-stage study. Propane and RP-1 fuels result in lower vehicle dry mass than methane, and staged-combustion engines are preferred over gas-generator engines. The sensitivity to the engine selection is less for two-stage systems than for single-stage systems.

Experimental Space Shuttle Orbiter Studies to Acquire Data for Code and Flight Heating Model Validation

NASA Technical Reports Server (NTRS)

Wadhams, T. P.; Holden, M. S.; MacLean, M. G.; Campbell, Charles

2010-01-01

In an experimental study to obtain detailed heating data over the Space Shuttle Orbiter, CUBRC has completed an extensive matrix of experiments using three distinct models and two unique hypervelocity wind tunnel facilities. This detailed data will be employed to assess heating augmentation due to boundary layer transition on the Orbiter wing leading edge and wind side acreage with comparisons to computational methods and flight data obtained during the Orbiter Entry Boundary Layer Flight Experiment and HYTHIRM during STS-119 reentry. These comparisons will facilitate critical updates to be made to the engineering tools employed to make assessments about natural and tripped boundary layer transition during Orbiter reentry. To achieve the goals of this study data was obtained over a range of Mach numbers from 10 to 18, with flight scaled Reynolds numbers and model attitudes representing key points on the Orbiter reentry trajectory. The first of these studies were performed as an integral part of Return to Flight activities following the accident that occurred during the reentry of the Space Shuttle Columbia (STS-107) in February of 2003. This accident was caused by debris, which originated from the foam covering the external tank bipod fitting ramps, striking and damaging critical wing leading edge heating tiles that reside in the Orbiter bow shock/wing interaction region. During investigation of the accident aeroheating team members discovered that only a limited amount of experimental wing leading edge data existed in this critical peak heating area and a need arose to acquire a detailed dataset of heating in this region. This new dataset was acquired in three phases consisting of a risk mitigation phase employing a 1.8% scale Orbiter model with special temperature sensitive paint covering the wing leading edge, a 0.9% scale Orbiter model with high resolution thin-film instrumentation in the span direction, and the primary 1.8% scale Orbiter model with detailed

Monitoring objects orbiting earth using satellite-based telescopes

DOEpatents

Olivier, Scot S.; Pertica, Alexander J.; Riot, Vincent J.; De Vries, Willem H.; Bauman, Brian J.; Nikolaev, Sergei; Henderson, John R.; Phillion, Donald W.

2015-06-30

An ephemeris refinement system includes satellites with imaging devices in earth orbit to make observations of space-based objects ("target objects") and a ground-based controller that controls the scheduling of the satellites to make the observations of the target objects and refines orbital models of the target objects. The ground-based controller determines when the target objects of interest will be near enough to a satellite for that satellite to collect an image of the target object based on an initial orbital model for the target objects. The ground-based controller directs the schedules to be uploaded to the satellites, and the satellites make observations as scheduled and download the observations to the ground-based controller. The ground-based controller then refines the initial orbital models of the target objects based on the locations of the target objects that are derived from the observations.

Disruption of postural readaptation by inertial stimuli following space flight

NASA Technical Reports Server (NTRS)

Black, F. O.; Paloski, W. H.; Reschke, M. F.; Igarashi, M.; Guedry, F.; Anderson, D. J.

1999-01-01

Postural instability (relative to pre-flight) has been observed in all shuttle astronauts studied upon return from orbital missions. Postural stability was more closely examined in four shuttle astronaut subjects before and after an 8 day orbital mission. Results of the pre- and post-flight postural stability studies were compared with a larger (n = 34) study of astronauts returning from shuttle missions of similar duration. Results from both studies indicated that inadequate vestibular feedback was the most significant sensory deficit contributing to the postural instability observed post flight. For two of the four IML-1 astronauts, post-flight postural instability and rate of recovery toward their earth-normal performance matched the performance of the larger sample. However, post-flight postural control in one returning astronaut was substantially below mean performance. This individual, who was within normal limits with respect to postural control before the mission, indicated that recovery to pre-flight postural stability was also interrupted by a post-flight pitch plane rotation test. A similar, though less extreme departure from the mean recovery trajectory was present in another astronaut following the same post-flight rotation test. The pitch plane rotation stimuli included otolith stimuli in the form of both transient tangential and constant centripetal linear acceleration components. We inferred from these findings that adaptation on orbit and re-adaptation on earth involved a change in sensorimotor integration of vestibular signals most likely from the otolith organs.

Simulation of nap-of-the-Earth flight in helicopters

NASA Technical Reports Server (NTRS)

Condon, Gregory W.

1991-01-01

NASA-Ames along with the U.S. Army has conducted extensive simulation studies of rotorcraft in the nap-of-the-Earth (NOE) environment and has developed facility capabilities specifically designed for this flight regime. The experience gained to date in applying these facilities to the NOE flight regime are reported along with the results of specific experimental studies conducted to understand the influence of both motion and visual scene on the fidelity of NOE simulation. Included are comparisons of results from concurrent piloted simulation and flight research studies. The results of a recent simulation experiment to study simulator sickness in this flight regime is also discussed.

Close up view of the Commander's Seat on the Flight ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Close up view of the Commander's Seat on the Flight Deck of the Orbiter Discovery. Toward the right of the view and in front of te seat is the commander's Rotational Hand Controller. The pilot station has an identical controller. These control the acceleration in the roll pitch and yaw directions via the reaction control system and/or the orbiter maneuvering system while outside of Earth's atmosphere or via the orbiter's aerosurfaces wile in Earth's atmosphere when the atmospheric density permits the surfaces to be effective. There are a number of switches on the controller, most notably a trigger switch which is a push-to-talk switch for voice communication and a large button on top of the controller which is a switch to engage the backup flight system. This view was taken at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

NASA's Earth Science Flight Program Meets the Challenges of Today and Tomorrow

NASA Technical Reports Server (NTRS)

Ianson, Eric E.

2016-01-01

NASA's Earth science flight program is a dynamic undertaking that consists of a large fleet of operating satellites, an array of satellite and instrument projects in various stages of development, a robust airborne science program, and a massive data archiving and distribution system. Each element of the flight program is complex and present unique challenges. NASA builds upon its successes and learns from its setbacks to manage this evolving portfolio to meet NASA's Earth science objectives. NASA fleet of 16 operating missions provide a wide range of scientific measurements made from dedicated Earth science satellites and from instruments mounted to the International Space Station. For operational missions, the program must address issues such as an aging satellites operating well beyond their prime mission, constellation flying, and collision avoidance with other spacecraft and orbital debris. Projects in development are divided into two broad categories: systematic missions and pathfinders. The Earth Systematic Missions (ESM) include a broad range of multi-disciplinary Earth-observing research satellite missions aimed at understanding the Earth system and its response to natural and human-induced forces and changes. Understanding these forces will help determine how to predict future changes, and how to mitigate or adapt to these changes. The Earth System Science Pathfinder (ESSP) program provides frequent, regular, competitively selected Earth science research opportunities that accommodate new and emerging scientific priorities and measurement capabilities. This results in a series of relatively low-cost, small-sized investigations and missions. Principal investigators whose scientific objectives support a variety of studies lead these missions, including studies of the atmosphere, oceans, land surface, polar ice regions, or solid Earth. This portfolio of missions and investigations provides opportunity for investment in innovative Earth science that enhances

Orbital and Physical Characteristics of Meter-sized Earth Impactors

NASA Astrophysics Data System (ADS)

Brown, Peter G.; Wiegert, Paul; Clark, David; Tagliaferri, Edward

2015-11-01

We have analysed the orbits and ablation characteristics in the atmosphere of more than 60 earth-impacting meteoroids of one meter in diameter or larger. Using heights at peak luminosity as a proxy for strength, we find that there is roughly an order of magnitude spread in the apparent strength of the population of meter-sized impactors at the Earth. The orbits and physical strength of these objects are consistent with the majority being asteroidal bodies originating from the inner main asteroid belt. We find ~10-15% of our objects have a probable cometary (Jupiter-Family comet and/or Halley-type comet) origin based on orbital characteristics alone. Only half this number, however, show evidence for the expected weaker than average structure compared to asteroidal bodies. Almost all impactors show peak brightness between 20-40 km altitude. Several events have exceptionally high (relative to the remainder of the population) heights of peak brightness. These are physically most consistent with high microporosity objects, though all were on asteroidal-type orbits. We also find three events, including the Oct 8, 2009 airburst near Sulawesi, Indonesia, which display comparatively low heights of peak brightness, consistent with strong monolithic stones or iron meteoroids. Based on orbital similarity, we find a probable connection among several NEOs in our population with the Taurid meteoroid complex. No other major meteoroid streams show linkages with the pre-atmospheric orbits of our meter-class impactors. Our events cover almost four orders of magnitude in mass, but no trend in height of peak brightness is evident, suggesting no strong trend in strength with size for small NEOs, a finding consistent with the results of Popova et al (2011).

Summary results of the first United States manned orbital space flight

NASA Technical Reports Server (NTRS)

Glenn, J. H. Jr

1963-01-01

This paper describes the principal findings of the first United States manned orbital space flight in light of the flight mission. Consideration is given to the coordinated tracking network, recovery forces and to the spacecraft and its several functional systems. These include mechanisms for heat protection, escape maneuvers, spacecraft control, power supply, communications, life support and landing. A few difficulties encountered in the flight and deviations from the planned sequence are described. Craft preparation, aeromedical studies, flight plan and particularly flight observations--including the color, light, horizon visibility by day and by night, cloud formations and sunrise and sunset effects are given in some detail. The general conclusion from the MA-6 flight is that man can adapt well to new conditions encountered in space flight and that man can contribute importantly to mission reliability and toward mission achievement through his capacities to control the spacecraft and its multiple systems contribute to decision making and adaptation of programming as well as to direct exploratory and experimental observations.

Parabolic flight - Loss of sense of orientation

NASA Technical Reports Server (NTRS)

Lackner, J. R.; Graybiel, A.

1979-01-01

On the earth, or in level flight, a blindfolded subject being rotated at constant velocity about his recumbent long body axis experiences illusory orbital motion of his body in the opposite direction. By contrast, during comparable rotation in the free-fall phase of parabolic flight, no body motion is perceived and all sense of external orientation may be lost; when touch and pressure stimulation is applied to the body surface, a sense of orientation is reestablished immediately. The increased gravitoinertial force period of a parabola produces an exaggeration of the orbital motion experienced in level flight. These observations reveal an important influence of touch, pressure, and kinesthetic information on spatial orientation and provide a basis for understanding many of the postural illusions reported by astronauts in space flight.

Magnus Effect on a Spinning Satellite in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Ramjatan, Sahadeo; Fitz-Coy, Norman; Yew, Alvin Garwai

2016-01-01

A spinning body in a flow field generates an aerodynamic lift or Magnus effect that displaces the body in a direction normal to the freestream flow. Earth orbiting satellites with substantial body rotation in appreciable atmospheric densities may generate a Magnus force to perturb orbital dynamics. We investigate the feasibility of using this effect for spacecraft at a perigee of 80km using the Systems Tool Kit (STK). Results show that for a satellite of reasonable properties, the Magnus effect doubles the amount of time in orbit. Orbital decay was greatly mitigated for satellites spinning at 10000 and 15000RPM. This study demonstrates that the Magnus effect has the potential to sustain a spacecraft's orbit at a low perigee altitude and could also serve as an orbital maneuver capability.

In-flight measurement of the National Oceanic and Atmospheric Administration (NOAA)-10 static Earth sensor error

NASA Technical Reports Server (NTRS)

Harvie, E.; Filla, O.; Baker, D.

1993-01-01

Analysis performed in the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) measures error in the static Earth sensor onboard the National Oceanic and Atmospheric Administration (NOAA)-10 spacecraft using flight data. Errors are computed as the difference between Earth sensor pitch and roll angle telemetry and reference pitch and roll attitude histories propagated by gyros. The flight data error determination illustrates the effect on horizon sensing of systemic variation in the Earth infrared (IR) horizon radiance with latitude and season, as well as the effect of anomalies in the global IR radiance. Results of the analysis provide a comparison between static Earth sensor flight performance and that of scanning Earth sensors studied previously in the GSFC/FDD. The results also provide a baseline for evaluating various models of the static Earth sensor. Representative days from the NOAA-10 mission indicate the extent of uniformity and consistency over time of the global IR horizon. A unique aspect of the NOAA-10 analysis is the correlation of flight data errors with independent radiometric measurements of stratospheric temperature. The determination of the NOAA-10 static Earth sensor error contributes to realistic performance expectations for missions to be equipped with similar sensors.

Manned space flight nuclear system safety. Volume 1: base nuclear system safety

NASA Technical Reports Server (NTRS)

1972-01-01

The mission and terrestrial nuclear safety aspects of future long duration manned space missions in low earth orbit are discussed. Nuclear hazards of a typical low earth orbit Space Base mission (from natural sources and on-board nuclear hardware) have been identified and evaluated. Some of the principal nuclear safety design and procedural considerations involved in launch, orbital, and end of mission operations are presented. Areas of investigation include radiation interactions with the crew, subsystems, facilities, experiments, film, interfacing vehicles, nuclear hardware and the terrestrial populace. Results of the analysis indicate: (1) the natural space environment can be the dominant radiation source in a low earth orbit where reactors are effectively shielded, (2) with implementation of safety guidelines the reactor can present a low risk to the crew, support personnel, the terrestrial populace, flight hardware and the mission, (3) ten year missions are feasible without exceeding integrated radiation limits assigned to flight hardware, and (4) crew stay-times up to one year are feasible without storm shelter provisions.

The Prevalence of Earth-size Planets Orbiting Sun-like Stars

NASA Astrophysics Data System (ADS)

Petigura, Erik; Marcy, Geoffrey W.; Howard, Andrew

2015-01-01

In less than two decades since the discovery of the first planet orbiting another Sun-like star, the study of extrasolar planets has matured beyond individual discoveries to detailed characterization of the planet population as a whole. No mission has played more of a role in this paradigm shift than NASA's Kepler mission. Kepler photometry has shown that planets like Earth are common throughout the Milky Way Galaxy. Our group performed an independent search of Kepler photometry using our custom transit-finding pipeline, TERRA, and produced our own catalog of planet candidates. We conducted spectroscopic follow-up of their host stars in order to rule out false positive scenarios and to better constrain host star properties. We measured TERRA's sensitivity to planets of different sizes and orbital periods by injecting synthetic planets into raw Kepler photometry and measuring the recovery rate. Correcting for orbital tilt and survey completeness, we found that ~80% of GK stars harbor one or more planets within 1 AU and that ~22% of Sun-like stars harbor an Earth-size planet that receives similar levels of stellar radiation as Earth. I will present the latest results from our efforts to characterize the demographics of small planets revealed by Kepler.

The Space Shuttle Program Pre-Flight Meteoroid and Orbital Debris Risk/Damage Predictions and Post-Flight Damage Assessments

NASA Technical Reports Server (NTRS)

Levin, George M.; Christiansen, Eric L.

1997-01-01

The pre-flight predictions and postflight assessments carried out in relation to a series of Space Shuttle missions are reviewed, and data are presented for the meteoroid and orbital debris damage observed on the Hubble Space Telescope during the 1994 Hubble repair mission. Pre-flight collision risk analyses are carried out prior to each mission, and in the case of an unacceptable risk, the mission profile is altered until the risk is considered to be acceptable. The NASA's BUMPER code is used to compute the probability of damage from debris and meteoroid particle impacts based on the Poisson statistical model for random events. The penetration probability calculation requires information concerning the geometry of the critical systems, the penetration resistance and mission profile parameters. Following each flight, the orbiter is inspected for meteoroid and space debris damage. The emphasis is on areas such as the radiator panels, the windows and the reinforced carbon-carbon structures on the leading wing edges and on the nose cap. The contents of damage craters are analyzed using a scanning electron microscope to determine the nature and origin of the impactor. Hypervelocity impact tests are often performed to simulate the observed damage and to estimate the nature of the damaging particles. The number and type of damage observed provides information concerning the orbital debris environment.

STS-40 Columbia, Orbiter Vehicle (OV) 102, crew insignia

NASA Image and Video Library

1990-05-01

STS40-S-001 (May 1990) --- The STS-40 patch makes a contemporary statement focusing on human beings living and working in space. Against a background of the universe, seven silver stars, interspersed about the Orbital path of the space shuttle Columbia, represent the seven crew members. The orbiter's flight path forms a double-helix, designed to represent the DNA molecule common to all living creatures. In the words of a crew spokesman, "...(the helix) affirms the ceaseless expansion of human life and American involvement in space while simultaneously emphasizing the medical and biological studies to which this flight is dedicated." Above Columbia, the phrase "Spacelab Life Sciences 1" defines both the shuttle mission and its payload. Leonardo Da Vinci's Vitruvian man, silhouetted against the blue darkness of the heavens, is in the upper center portion of the patch. With one foot on Earth and arms extended to touch shuttle's orbit, the crew feels, he serves as a powerful embodiment of the extension of human inquiry from the boundaries of Earth to the limitless laboratory of space. Sturdily poised amid the stars, he serves to link scentists on Earth to the scientists in space asserting the harmony of efforts which produce meaningful scientific spaceflight missions. A brilliant red and yellow Earth limb (center) links Earth to space as it radiates from a native American symbol for the sun. At the frontier of space, the traditional symbol for the sun vividly links America's past to America's future, the crew states. Beneath the orbiting space shuttle, darkness of night rests peacefully over the United States. Drawn by artist Sean Collins, the STS-40 space shuttle patch was designed by the crew members for the flight. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media

Study of multi-kW solar arrays for Earth orbit application

NASA Technical Reports Server (NTRS)

1980-01-01

Low cost low Earth orbit (LOW) and geosynchronous Earth orbit (GEO) Solar Array concepts in the 300 to 1000 kW range which could be reduced to hardware in the mid 1980's, are identified. Size scaling factors and longer life demands are recognized as the prime drivers for the designs if low life cycle costs for energy are to be achieved. Technology is identified which requires further development in order to assure component readiness and availability. Use of the low concentration ratio (CR) concentrator, which uses gallium arsenide solar cells for both LEO and GEO applications, is recommended.

Tests of general relativity in earth orbit using a superconducting gravity gradiometer

NASA Technical Reports Server (NTRS)

Paik, H. J.

1989-01-01

Interesting new tests of general relativity could be performed in earth orbit using a sensitive superconducting gravity gradiometer under development. Two such experiments are discussed here: a null test of the tracelessness of the Riemann tensor and detection of the Lense-Thirring term in the earth's gravity field. The gravity gradient signals in various spacecraft orientations are derived, and dominant error sources in each experimental setting are discussed. The instrument, spacecraft, and orbit requirements imposed by the experiments are derived.

Using The Global Positioning System For Earth Orbiter and Deep Space Network

NASA Technical Reports Server (NTRS)

Lichten, Stephen M.; Haines, Bruce J.; Young, Lawrence E.; Dunn, Charles; Srinivasan, Jeff; Sweeney, Dennis; Nandi, Sumita; Spitzmesser, Don

1994-01-01

The Global Positioning System (GPS) can play a major role in supporting orbit and trajectory determination for spacecraft in a wide range of applications, including low-Earth, high-earth, and even deep space (interplanetary) tracking.

High Earth orbit design for lunar assisted small Explorer class missions

NASA Technical Reports Server (NTRS)

Mathews, M.; Hametz, M.; Cooley, J.; Skillman, D.

1994-01-01

Small Expendable launch vehicles are capable of injecting modest payloads into high Earth orbits having apogee near the lunar distance. However, lunar and solar perturbations can quickly lower perigee and cause premature reentry. Costly perigee raising maneuvers by the spacecraft are required to maintain the orbit. In addition, the range of inclinations achievable is limited to those of launch sites unless costly spacecraft maneuvers are performed. This study investigates the use of a lunar swingby in a near-Hohmann transfer trajectory to raise perigee into the 8 to 25 solar radius range and reach a wide variety of inclinations without spacecraft maneuvers. It is found that extremely stable orbits can be obtained if the postencounter spacecraft orbital period is one-half of a lunar sidereal revolution and the Earth-vehicle-Moon geometry is within a specified range. Criteria for achieving stable orbits with various perigee heights and ecliptic inclinations are developed, and the sensitivity of the resulting mission orbits to transfer trajectory injection (TTI) errors is examined. It is shown that carefully designed orbits yield lifetimes of several years, with excellent ground station coverage characteristics and minimal eclipses. A phasing loop error correction strategy is considered with the spacecraft propulsion system delta V demand for TTI error correction and a postlunar encounter apogee trim maneuver typically in the 30 to 120 meters per second range.

The B-dot Earth Average Magnetic Field

NASA Technical Reports Server (NTRS)

Capo-Lugo, Pedro A.; Rakoczy, John; Sanders, Devon

2013-01-01

The average Earth's magnetic field is solved with complex mathematical models based on mean square integral. Depending on the selection of the Earth magnetic model, the average Earth's magnetic field can have different solutions. This paper presents a simple technique that takes advantage of the damping effects of the b-dot controller and is not dependent of the Earth magnetic model; but it is dependent on the magnetic torquers of the satellite which is not taken into consideration in the known mathematical models. Also the solution of this new technique can be implemented so easily that the flight software can be updated during flight, and the control system can have current gains for the magnetic torquers. Finally, this technique is verified and validated using flight data from a satellite that it has been in orbit for three years.

Human Space Flight

NASA Technical Reports Server (NTRS)

Woolford, Barbara; Mount, Frances

2004-01-01

The first human space flight, in the early 1960s, was aimed primarily at determining whether humans could indeed survive and function in micro-gravity. Would eating and sleeping be possible? What mental and physical tasks could be performed? Subsequent programs increased the complexity of the tasks the crew performed. Table 1 summarizes the history of U.S. space flight, showing the projects, their dates, crew sizes, and mission durations. With over forty years of experience with human space flight, the emphasis now is on how to design space vehicles, habitats, and missions to produce the greatest returns to human knowledge. What are the roles of the humans in space flight in low earth orbit, on the moon, and in exploring Mars?

The orbit and size distribution of small Solar System objects orbiting the Sun interior to the Earth's orbit

NASA Astrophysics Data System (ADS)

Zavodny, Maximilian; Jedicke, Robert; Beshore, Edward C.; Bernardi, Fabrizio; Larson, Stephen

2008-12-01

We present the first observational measurement of the orbit and size distribution of small Solar System objects whose orbits are wholly interior to the Earth's (Inner Earth Objects, IEOs, with aphelion <0.983 AU). We show that we are able to model the detections of near-Earth objects (NEO) by the Catalina Sky Survey (CSS) using a detailed parameterization of the CSS survey cadence and detection efficiencies as implemented within the Jedicke et al. [Jedicke, R., Morbidelli, A., Spahr, T., Petit, J.M., Bottke, W.F., 2003. Icarus 161, 17-33] survey simulator and utilizing the Bottke et al. [Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H.F., Michel, P., Metcalfe, T.S., 2002. Icarus 156, 399-433] model of the NEO population's size and orbit distribution. We then show that the CSS detections of 4 IEOs are consistent with the Bottke et al. [Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H.F., Michel, P., Metcalfe, T.S., 2002. Icarus 156, 399-433] IEO model. Observational selection effects for the IEOs discovered by the CSS were then determined using the survey simulator in order to calculate the corrected number and H distribution of the IEOs. The actual number of IEOs with H<18 (21) is 36±26 ( 530±240) and the slope of the H magnitude distribution ( ∝10) for the IEOs is α=0.44-0.22+0.23. The slope is consistent with previous measurements for the NEO population of α=0.35±0.02 [Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H.F., Michel, P., Metcalfe, T.S., 2002. Icarus 156, 399-433] and α=0.39±0.013 [Stuart, J.S., Binzel, R.P., 2004. Icarus 170, 295-311]. Based on the agreement between the predicted and observed IEO orbit and absolute magnitude distributions there is no indication of any non-gravitational effects (e.g. Yarkovsky, tidal disruption) affecting the known IEO population.

Earth-orbit mission considerations and Space Tug requirements.

NASA Technical Reports Server (NTRS)

Huber, W. G.

1973-01-01

The reusable Space Tug is a major system planned to augment the Space Shuttle's capability to deliver, retrieve, and support automated payloads. The Space Tug will be designed to perform round-trip missions from low earth orbit to geosynchronous orbit. Space Tug goals and requirements are discussed together with the characteristics of the full capability Tug. The Tug is to be operated in an unmanned 'teleoperator' fashion. Details of potential teleoperator applications are considered, giving attention to related systems studies, candidate Tug mission applications, Tug 'end-effector' alternatives, technical issues associated with Tug payload retrieval, and Tug/payload accommodations.

In-Flight and Post-Flight Impact Data Analysis from DEBIE2 (Debris In-Orbit Evaluator) on Board of ISS

NASA Astrophysics Data System (ADS)

Menicucci, Alessandra; Drolshagen, Gerhard; Kuitunen, Juha; Butenko, Yuriy; Mooney, Cathal

2013-08-01

DEBIE2 (Debris-in-orbit-evaluator) was launched in February 2008 as part of the European Technology Exposure Facility (EuTEF) and installed on the exterior of Columbus on ISS. DEBIE2 is an active detector, composed by 3 sensor units able to monitor the sub-micron micro-meteoroid and debris population in space. Each DEBIE sensor consists of a thin aluminium foil coupled with 2 wire grids sensitive to the plasma generated by particles impacting on the foil where also 2 piezoelectric sensors are glued. If the particle penetrates the foil, this can be detected by a third electron plasma detector located just behind the foil. The combination of these information allows to estimate the micro-particles and debris fluxes. EuTEF and DEBIE2 were retrieved after 18 months in flight and returned to Earth with the Space Shuttle Mission STS-128. In this paper, the results of the analysis of in-flight impact data are presented as well as the comparison with the models. The DEBIE2 sensor pointing the Zenith direction, was found to have one wire of the upper grid cut in two pieces by an impact. The postflight analysis focused on this sensor and included optical and SEM/EDX scanning. The results from this inspection will be also presented in this paper.