Science.gov

Sample records for 900-mile sea voyage

  1. Voyager.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This paper provides an overview of the Voyager Expanded Learning programs. Initially begun with hands-on, activity-based learning experiences centered around academic themes designed to pique children's interest and motivate them to learn, Voyager has expanded from elementary after- and summer-school programs to include K-8 programs designed for…

  2. Chronicles of the Sea: The History and Literature of Man's Voyages.

    ERIC Educational Resources Information Center

    Roderer, Lawrence C.; Lacy, Richard

    In spring 1984, an interdisciplinary course on the history and literature of man's voyages and relationship with the sea was introduced at J. Sargeant Reynolds Community College (JSRCC). The course was team taught from the perspectives of the social sciences and English departments, incorporating fiction and non-fiction sources related to…

  3. Captain Cook's beer: the antiscorbutic use of malt and beer in late 18th century sea voyages.

    PubMed

    Stubbs, Brett J

    2003-01-01

    The custom of allowing British seamen the regular use of fermented liquor is an old one. Ale was a standard article of the sea ration as early as the fourteenth century. By the late eighteenth century, beer was considered to be at once a food (a staple beverage and essential part of the sea diet), a luxury (helping to ameliorate the hardship and irregularity of sea life) and a medicine (conducive to health at sea). In particular, beer and its precursors, wort and malt, were administered with the aim of preventing and curing scurvy. This paper examines the use of malt and beer during late eighteenth century British sea voyages, particularly their use as antiscorbutic agents, focusing on James Cook's three voyages during the period 1768-1780. Cook administered sweet wort (an infusion of malt), beer (prepared from an experimental, concentrated malt extract), and spruce beer (prepared mainly from molasses), among many other items, in his attempts to prevent and to cure scurvy. Despite the inconclusive nature of his own experiments, he reported favourably after his second voyage (1772-1775) on the use of wort as an antiscorbutic sea medicine (for which purpose it is now known to be useless). Cook thereby lent credibility to erroneous medical theories about scurvy, helping to perpetuate the use of ineffective treatments and to delay the discovery of a cure for the disorder. PMID:12810402

  4. Metagenomic sequencing reveals altered metabolic pathways in the oral microbiota of sailors during a long sea voyage

    PubMed Central

    Zheng, Weiwei; Zhang, Ze; Liu, Cuihua; Qiao, Yuanyuan; Zhou, Dianrong; Qu, Jia; An, Huaijie; Xiong, Ming; Zhu, Zhiming; Zhao, Xiaohang

    2015-01-01

    Seafaring is a difficult occupation, and sailors face higher health risks than individuals on land. Commensal microbiota participates in the host immune system and metabolism, reflecting the host's health condition. However, the interaction mechanisms between the microbiota and the host's health condition remain unclear. This study reports the influence of long sea voyages on human health by utilising a metagenomic analysis of variation in the microbiota of the buccal mucosa. Paired samples collected before and after a sea-voyage were analysed. After more than 120 days of ocean sailing, the oral microbial diversity of sailors was reduced by approximately 5 fold, and the levels of several pathogens (e.g., Streptococcus pneumonia) increased. Moreover, 69.46% of the identified microbial sequences were unclassified microbiota. Notably, several metabolic pathways were dramatically decreased, including folate biosynthesis, carbohydrate, lipid and amino acid pathways. Clinical examination of the hosts confirmed the identified metabolic changes, as demonstrated by decreased serum levels of haemoglobin and folic acid, a decreased neutrophil-to-lymphocyte ratio, and increased levels of triglycerides, cholesterol and homocysteine, which are consistent with the observed microbial variation. Our study suggests that oral mucosal bacteria may reflect host health conditions and could provide approaches for improving the health of sailors. PMID:26154405

  5. Metagenomic sequencing reveals altered metabolic pathways in the oral microbiota of sailors during a long sea voyage.

    PubMed

    Zheng, Weiwei; Zhang, Ze; Liu, Cuihua; Qiao, Yuanyuan; Zhou, Dianrong; Qu, Jia; An, Huaijie; Xiong, Ming; Zhu, Zhiming; Zhao, Xiaohang

    2015-01-01

    Seafaring is a difficult occupation, and sailors face higher health risks than individuals on land. Commensal microbiota participates in the host immune system and metabolism, reflecting the host's health condition. However, the interaction mechanisms between the microbiota and the host's health condition remain unclear. This study reports the influence of long sea voyages on human health by utilising a metagenomic analysis of variation in the microbiota of the buccal mucosa. Paired samples collected before and after a sea-voyage were analysed. After more than 120 days of ocean sailing, the oral microbial diversity of sailors was reduced by approximately 5 fold, and the levels of several pathogens (e.g., Streptococcus pneumonia) increased. Moreover, 69.46% of the identified microbial sequences were unclassified microbiota. Notably, several metabolic pathways were dramatically decreased, including folate biosynthesis, carbohydrate, lipid and amino acid pathways. Clinical examination of the hosts confirmed the identified metabolic changes, as demonstrated by decreased serum levels of haemoglobin and folic acid, a decreased neutrophil-to-lymphocyte ratio, and increased levels of triglycerides, cholesterol and homocysteine, which are consistent with the observed microbial variation. Our study suggests that oral mucosal bacteria may reflect host health conditions and could provide approaches for improving the health of sailors. PMID:26154405

  6. Causes and Circumstances of Deaths of Polish Seafarers During Sea Voyages.

    PubMed

    Jaremin; Kotulak; Starnawska; Tomaszunas

    1996-06-01

    Background: The safety of life and work at sea depends, among other things, on the state of health of the members of the crew. Despite preliminary fitness selection, death at sea is still frequent. In the present paper, causes and circumstances of fatal cases at sea in the years 1985-1994 were analyzed for one Polish shipping company. Methods: Analysis was based on medical documentation and reports of accidents prepared by health centers, the employer and the marine judiciary. The effects of work conditions, as well as disease, on the resulting death were taken into account. The data obtained were compared to the mortality in nonseafaring men of productive age. Results: The most frequent causes of deaths were sea catastrophes, circulatory system diseases, injuries, and poisonings (a total of 85%). Next were suicides, "missings," and cerebral apoplexies. Seamen of 50 to 59 years of age died most often, primarily of myocardial infarction. Fatal events occurred in different places (mostly at sea, less frequently in port). Certain onboard occupations were identified as most dangerous for fatal accidents. The shipowner acknowledged 60% of the deaths as accidents at work. The effects of weather conditions, stress, overstrain, and lack of access to qualified medical assistance were analyzed. A relationship between diagnosed disease and death was found only in the case of myocardial infarction and cerebral apoplexy. In scarcely 15% of these cases were preliminary symptoms noticed, while behavioral and personality disturbances were earlier observed in the majority of suicides. Conclusions: The ship has remained one of the most dangerous workplaces, and fatal cases are to a large extent related to specific labor conditions at sea.

  7. C-IMAGE Teachers at Sea Maiden Voyages: Promoting Authentic Scientific Research in the Classroom

    NASA Astrophysics Data System (ADS)

    Hine, A. C.; Greely, T.; Lodge, A.

    2012-12-01

    The Center for Integrated Modeling & Analysis of Gulf Ecosystems (C-IMAGE) is one of eight consortia participating in the BP/Gulf of Mexico Research Initiative. C-IMAGE is a comprehensive research consortium of 13 national and international universities tasked with evaluating the environmental impacts of the 2010 Deepwater Horizon Oil Spill (DWH) on coastal ecosystems, the water column and the sea floor. The associated C-IMAGE research cruises provide a unique opportunity for Florida's K12 science educators to participate in the data collection and collaboration process alongside marine scientists as a member of the scientific crew. The mission of the C-IMAGE cruises is to help to answer several fundamental questions about the DWH event and subsequent impacts on the plankton population, reef and fish communities and the microbial communities. Deep sea sediment samples, plankton and fishes collected during these expeditions are the data sources. Sampling activities include the use of the SIPPER plankton sampler, multi-core sediment system and long line surveys to assess fish health. While at sea teachers participate in the at sea research and serve as the ship to shore communicator via social media (FB, Twitter, daily blogs) and LIVE video conferencing with formal and informal classrooms. Marine scientists, post-docs and graduate students participating in the C-IMAGE cruises collaborate with the teacher on board to communicate the science, technology and life at sea experiences to educational and general audiences. Upon return to shore, teachers will translate their At Sea learning experience to understandable inquiry-based lessons about the science and technology encompassing the northern Gulf of Mexico ecology, the DWH event and subsequent impacts. Lessons developed from the cruises will inform a future series of C-IMAGE Teacher Professional Developments during Phase 2 of Outreach activities. The results from three Gulf of Mexico expeditions (Aug-Nov) will be

  8. Voyager 2 Jupiter encounter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A NASA News Release is presented which contains the following: (1) general release; (2) two views of Voyager 2 flight past Jupiter; (3) Voyager mission summary; (4) Voyager 1 science results; (5) Jupiter science objectives; (6) Jupiter the planet and its satellites; (7) Voyager experiments; (8) planet comparison; (9) a list of Voyager science investigators and (10) the Voyager team.

  9. Voyager backgrounder

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The Voyager spacecraft and experiments are described. The spacecraft description includes the structure and configuration, communications systems, power supplies, computer command subsystems, and the science platform. The experiments discussed are investigations of cosmic rays, low-energy charged particles, magnetic fields, and plasma waves, along with studies in radio astronomy photopolarimetry. The tracking and data acquisition procedures for the missions are presented.

  10. Voyager Cartography

    NASA Technical Reports Server (NTRS)

    Batson, R. M.; Bridges, P. M.; Mullins, K. F.

    1985-01-01

    The Jovian and Saturnian satellites are being mapped at several scales from Voyager 1 and 2 data. The maps include specially formatted color mosaics, controlled photomosaics, and airbrush maps. More than 500 Voyager images of the Jovian and Saturnian satellites were radiometrically processed in preparation for cartographic processing. Of these images, 235 were geometrically transformed to map projections for base mosaic compilations. Special techniques for producing hybrid photomosaic/airbrush maps of Callisto are under investigation. The techniques involve making controlled computer mosaics of all available images with highest resolution images superimposed on lowest resolution images. The mosaics are then improved by airbrushing: seams and artifacts are removed, and image details enhanced that had been lost by saturation in some images. A controlled mosaic of the northern hemisphere of Rhea is complete, as is all processing for a similar mosaic of the equatorial region. Current plans and status of the various series are shown in a table.

  11. Voyager's decade of wonder

    SciTech Connect

    Mclaughlin, W.I. )

    1989-07-01

    The development and implementation of the Voyager missions are reviewed. The interplanetary missions preceding Voyager are discussed, focusing on the technological development leading up to the Voyager spacecraft. The main results from Voyager observations of Jupiter, Saturn, and Uranus are outlined. Also, consideration is given to the prospects for observations of Neptune.

  12. NASA Facts: Voyager

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A news release on NASA's Voyager project is presented. The spacecraft, science instrumentation, experiments and a mission profile are described. A drawing identifying Voyager's major components and instrumentation was included along with diagrams showing the path of Voyager 1 (JST trajectory) past Jupiter, and the path of Voyager 2 (JXT trajectory) during its encounter with Jupiter. An exercise for student involvement was also provided.

  13. Maiden voyage.

    PubMed

    De Santis, Dario

    2011-01-01

    The scientific debate which developed during the eighteenth century, proposed and diffused new theories on the generation not only within the scientific community. Microscopic investigation and various experimental campaigns fostered daring models attempting to unveil the natural phenomena from which life originates. Besides the famous scientific and philosophical works that marked the age, in the second part of the century two pamphlets appeared that well represent the importance of the querelle about embryological systems defining the concept of generation as a voyage within the human body. Lucina sine concubitu and Juno abortans, respectively published in England and in Germany between 1750 and 1760, narrate the odd and imaginary adventures of two doctors who are trying to interrupt and modify the embryos' journey towards the body of the mother. PMID:21936203

  14. Maiden voyage.

    PubMed

    De Santis, Dario

    2011-01-01

    The scientific debate which developed during the eighteenth century, proposed and diffused new theories on the generation not only within the scientific community. Microscopic investigation and various experimental campaigns fostered daring models attempting to unveil the natural phenomena from which life originates. Besides the famous scientific and philosophical works that marked the age, in the second part of the century two pamphlets appeared that well represent the importance of the querelle about embryological systems defining the concept of generation as a voyage within the human body. Lucina sine concubitu and Juno abortans, respectively published in England and in Germany between 1750 and 1760, narrate the odd and imaginary adventures of two doctors who are trying to interrupt and modify the embryos' journey towards the body of the mother.

  15. 46 CFR 188.10-35 - International voyage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in this subchapter shall have the same meaning as that contained in Regulation 2(d), Chapter I of the International Convention for Safety of Life at Sea, 1974, i.e., International voyage means a voyage from a... International Convention for Safety of Life at Sea, 1974, does not apply to vessels “solely navigating the...

  16. Voyager cartography

    NASA Technical Reports Server (NTRS)

    Batson, R. M.; Lee, E. M.; Mullins, K. F.

    1987-01-01

    The Jovian and Saturnian satellites are being mapped at several scales from Voyager 1 and 2 data. The maps are especially formatted color mosaics, controlled photomosaics, and airbrush maps. At 1:5,000,000 scale, mapping of Io, Europa, and Ganymede is complete. At 1:15,000,000 scale, mapping of Io and Europa is complete, and mapping of Ganymede is approximately complete. A controlled mosaic of Rhea has been compiled as a Digital Image Model (DIM) in the same format as is being used for Mars. The mosaic is being formatted for publication as a two-sheet set (Lambert Azimuthal Equal Area, Mercator, and Polar Stereographic projections). Magnetic tape copies of the DIM have been distributed to regional Planetary Image Facilities and other interested users. The DIM has a scale of 1/16 degree/pixel, corresponding to approximately 833 m/pixel on Rhea. Details of the status of the various map series are reported quarterly to Planetary Geology Principal Investigators.

  17. Voyager - Humanity's Farthest Journey

    NASA Video Gallery

    After 33 years, NASA's twin Voyager spacecraft are still going strong and still sending home information. This video features highlights of the Voyager journeys to the outer planets, and looks at t...

  18. Communicating with Voyager

    NASA Technical Reports Server (NTRS)

    Dumas, Larry N.; Hornstein, Robert M.

    1990-01-01

    The Deep Space Network for receiving Voyager 2 data is discussed. The functions of the earth-Voyager radio link are examined, including radiometrics, transmission of commands to the spacecraft, radio sciences, and the transmission of telemetry from the spacecraft to earth. The use of ranging, Doppler, and VLBI measurements to maintain position and velocity data on Voyager 2 is described. Emphasis is placed on the international tracking network for obtaining Voyager 2 data on Neptune and Triton.

  19. Voyager - 35 Years Later

    NASA Video Gallery

    This video drops in on mission control for NASA's Voyager spacecraft asVoyager 1 sends back data from the far reaches of our solar system.Credit: NASA/JPL-Caltech    › Voyager's mission site

  20. Voyager's Last Encounter

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This video describes Voyager 2's encounter with Neptune. Computer animation and actual data convey Voyager's discoveries such as turbulent storms and dark spots in Neptune's atmosphere, six new moons, Neptune's three rings, and the presence of frozen methane on Triton, as researchers at NASA's Jet Propulsion Laboratory describe Voyager's achievements.

  1. 46 CFR 180.10 - Applicability to vessels on an international voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Applicability to vessels on an international voyage. 180... Applicability to vessels on an international voyage. A vessel on an international voyage subject to the International Convention for the Safety of Life at Sea, 1974, (SOLAS) must meet the requirements in subchapter...

  2. Voyage of Discovery

    NASA Video Gallery

    These animations show NASA's Voyager spacecraft encountering Jupiter, Saturn, Uranus and Neptune on their grand tour through the solar system. The artist's renderings were made based on navigationa...

  3. Constraining back-arc basin formation in the eastern Coral Sea: preliminary results from the ECOSAT voyage

    NASA Astrophysics Data System (ADS)

    Seton, M.; Williams, S.; Mortimer, N. N.; Meffre, S.; Moore, J.; Micklethwaite, S.; Zahirovic, S.

    2013-12-01

    The eastern Coral Sea region is an underexplored area at the northeastern corner of the Australian plate, where long-lived interaction between the Pacific and Australian plate boundaries has resulted in an intricate assemblage of deep oceanic basins and ridges, continental fragments and volcanic products. A paucity of marine geophysical and geological data from this complex region has resulted in the lack of a clear conceptual framework to describe its formation, ultimately affecting our understanding of the connection between the plate boundaries of the SW Pacific and SE Asia. In particular, the tectonic relationship between two back-arc basins, the Santa Cruz and d'Entrecasteaux Basins, and the South Rennell Trough, has yet to be resolved. In October-November, 2012, we collected 6,200 km of marine magnetic, 6,800 km of gravity and over 13,600 km2 of swath bathymetry data from the eastern Coral Sea onboard the RV Southern Surveyor. A complementary dredging program yielded useful samples from 14 seafloor sites. Our preliminary geochemical interpretation of the dredge samples obtained from the South Rennell Trough reveal volcanic rocks resembling MORB or BABB-type basalts, similar in composition to the recently re-analysed and dated ORSTOM dredges from the area that yielded ~28 Ma MORB-like basalts. Swath bathymetry profiles from the Santa Cruz Basin reveal that the South Rennell Trough extends into this basin, with seafloor spreading fabric being parallel to the trough. Preliminary analysis of the three full and four partial new magnetic anomaly profiles across the Santa Cruz Basin, coupled with limited existing profiles, reveals that the basin may have formed between Chrons 13-18 (~32-38 Ma), with an extinct spreading ridge along the inferred continuation of the South Rennell Trough, consistent with ORSTOM age dates. Our results suggest that the South Rennell Trough is an extinct southwestward propagating spreading ridge, which may have initiated along a pre

  4. Voyager at Uranus: 1986

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The voyager 2 spacecraft begins its initial observations of Uranus November 4, 1985, and makes its final observation February 25, 1996. The data from the infrared interfermometer spectrometer, photopolarimeters, plasma wave, plasma detecter, and ultraviolet spectrometer will be processed to add a large block of infermation to the small amount already known. The trajectory of Voyager 2 is also discussed.

  5. Voyage to Jupiter.

    ERIC Educational Resources Information Center

    Morrison, David; Samz, Jane

    This publication illustrates the features of Jupiter and its family of satellites pictured by the Pioneer and the Voyager missions. Chapters included are: (1) "The Jovian System" (describing the history of astronomy); (2) "Pioneers to Jupiter" (outlining the Pioneer Mission); (3) "The Voyager Mission"; (4) "Science and Scientsts" (listing 11…

  6. The grandest tour - Voyager

    NASA Technical Reports Server (NTRS)

    Murrill, Mary B.

    1993-01-01

    The Voyager mission based on two spacecraft, Voyager 1 and Voyager 2, launched on September 5, 1977 and August 20 1977, respectively, is reviewed. The mission was designed to take advantage of a rare geometric arrangement of Jupiter, Saturn, Uranus, and Neptune that occurs only once every 176 years. Particular attention is given to data on Jupiter's ring and moons, the discovery of active volcanoes on Io, Jovian magnetism, Saturn's atmosphere, Titan and other moons, Uranus and Miranda, Uranian moons and rings, Triton's atmosphere.

  7. Voyager Interstellar Mission (VIM)

    NASA Technical Reports Server (NTRS)

    Rudd, R.; Textor, G.

    1991-01-01

    The DSN (Deep Space Network) mission support requirements for the Voyager Interstellar Mission (VIM) are summarized. The general objectives of the VIM are to investigate the interplanetary and interstellar media and to continue the Voyager program of ultraviolet astronomy. The VIM will utilize both Voyager spacecraft for the period from January 1990 through December 2019. The mission objectives are outlined and the DSN support requirements are defined through the presentation of tables and narratives describing the spacecraft flight profile; DSN support coverage; frequency assignments; support parameters for telemetry, control and support systems; and tracking support responsibility.

  8. Voyager at Neptune: 1989

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Voyager mission has taken advantage of a rare planetary alignment that occurs at intervals of about 175 years and affords an extraordinary opportunity: a grand tour by a single spacecraft of the outer planets Jupiter, Saturn, Uranus, and Neptune. Voyager 2 will fly past Nepture and its large moon Triton on August 24, 1989. The discovery of Neptune, along with its current history is discussed. The imaging challenges, tracking and data acquisition, and the Voyager spacecraft are explained. Data will be gathered on the ring arcs of Neptune, the atmosphere and surface of Neptune, Triton, and Nereid (the smaller moon).

  9. Artist's Concept of Voyager

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This artist's concept of the Voyager spacecraft with its antenna pointing to Earth. The identical Voyager spacecraft are three-axis stabilized systems that use celestial or gyro referenced attitude control to maintain pointing of the high-gain antennas toward Earth. The prime mission science payload consisted of 10 instruments (11 investigations including radio science). Only five investigator teams are still supported, though data are collected for two additional instruments.

  10. Voyages to Saturn

    NASA Technical Reports Server (NTRS)

    Morrison, D.

    1982-01-01

    The Voyager mission to Saturn is explained in detail. A history of Saturn observations from ancient times to the present is given. The Voyager spacecraft and their instruments are described. An overview of planetary astronomy is presented. The text is supplemented by numerous black and white and color photographs. The Saturn satellites are discussed in detail, and preliminary pictorial maps of the satellites are given.

  11. The Voyager magnetometer boom

    NASA Technical Reports Server (NTRS)

    Miller, D. C.

    1979-01-01

    The Voyager spacecraft magnetometer experiment utilizes two sensors on a deployable boom. The boom is an Astromast. The implementation of the Astromast into the Voyager design is described along with the hardware used to hold, latch, and deploy the mast and the tests to demonstrate damping, deployment, and alignments. Several problems encountered are discussed and their solutions are given. Flight deployment and preliminary alignment results are presented. Finally, the design is evaluated in retrospect.

  12. Voyager: Neptune Encounter Highlights

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Voyager encounter data are presented in computer animation (CA) and real (R) animation. The highlights include a view of 2 full rotations of Neptune. It shows spacecraft trajectory 'diving' over Neptune and intercepting Triton's orbit, depicting radiation and occulation zones. Also shown are a renegade orbit of Triton and Voyager's encounter with Neptune's Magnetopause. A model of the spacecraft's complex maneuvers during close encounters of Neptune and Triton is presented. A view from Earth of Neptune's occulation experiment is is shown as well as a recreation of Voyager's final pass. There is detail of Voyager's Image Compensation technique which produces Voyager images. Eighteen images were produced on June 22 - 23, 1989, from 57 million miles away. A 68 day sequence which provides a stroboscopic view - colorization approximates what is seen by the human eye. Real time images recorded live from Voyager on 8/24/89 are presented. Photoclinometry produced the topography of Triton. Three images are used to create a sequence of Neptune's rings. The globe of Neptune and 2 views of the south pole are shown as well as Neptune rotating. The rotation of a scooter is frozen in images showing differential motion. There is a view of rotation of the Great Dark Spot about its own axis. Photoclinometry provides a 3-dimensional perspective using a color mosaic of Triton images. The globe is used to indicate the orientation of Neptune's crescent. The east and west plumes on Triton are shown.

  13. Voyager Saturn encounter press briefing

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The briefing reviewed the mission planning of the Voyager project. The near encounter trajectories of both Voyager spacecraft were examined. The Saturn system is discussed with particular emphasis on Saturn's moons.

  14. Voyager 2 Observes Energetic Electrons

    NASA Video Gallery

    This animation shows the Voyager 2 observations of energetic electrons. Voyager 2 detected a dramatic drop of the flux of electrons as it left the sector region. The intense flux came back as soon ...

  15. Voyager picture of Jupiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA's Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, the first in its three-month-long, close-up investigation of the largest planet. The spacecraft, flying toward a March 5 closest approach, was 35.8 million miles (57.6 million kilometers) from Jupiter and 371.7 million miles (598.2 million kilometers) from Earth when the picture was taken. As the Voyager cameras begin their meteorological surveillance of Jupiter, they reveal a dynamic atmosphere with more convective structure than had previously been thought. While the smallest atmospheric features seen in this picture are still as large as 600 miles (1,000 kilometers) across, Voyager will be able to detect individual storm systems as small as 3 miles (5 kilometers) at closest approach. The Great Red Spot can be seen near the limb at the far right. Most of the other features are too small to be seen in terrestrial telescopes. This picture was transmitted to the Jet Propulsion Laboratory through the Deep Space Network's tracking station at Madrid, Spain. The Voyager Project is managed for NASA by Caltech's Jet Propulsion Laboratory.

  16. Voyager Outreach Compilation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This NASA JPL (Jet Propulsion Laboratory) video presents a collection of the best videos that have been published of the Voyager mission. Computer animation/simulations comprise the largest portion of the video and include outer planetary magnetic fields, outer planetary lunar surfaces, and the Voyager spacecraft trajectory. Voyager visited the four outer planets: Jupiter, Saturn, Uranus, and Neptune. The video contains some live shots of Jupiter (actual), the Earth's moon (from orbit), Saturn (actual), Neptune (actual) and Uranus (actual), but is mainly comprised of computer animations of these planets and their moons. Some of the individual short videos that are compiled are entitled: The Solar System; Voyage to the Outer Planets; A Tour of the Solar System; and the Neptune Encounter. Computerized simulations of Viewing Neptune from Triton, Diving over Neptune to Meet Triton, and Catching Triton in its Retrograde Orbit are included. Several animations of Neptune's atmosphere, rotation and weather features as well as significant discussion of the planet's natural satellites are also presented.

  17. NASA Facts, Voyager.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC. Educational Programs Div.

    This document is one of a series of publications of the National Aeronautics and Space Administration (NASA) on facts about the exploration of Jupiter and Saturn. This NASA mission consists of two unmanned Voyager spacecrafts launched in August and September of 1977, and due to arrive at Jupiter in 1979. An account of the scientific equipment…

  18. Two Voyagers to Saturn

    NASA Astrophysics Data System (ADS)

    1981-08-01

    The pages which follow may be taken as a celebration of the impending encounter of Voyager 2 with Saturn and are a pointer to the richness of data likely to be gathered in the next few days and weeks. Although there may be some to whom the work of these two remarkable spacecraft will be proof of how even more remarkable would have been the Grand Tour of the Solar System planned in the 1960s but executed only in the form of the two Voyagers, to most people the encounters with Jupiter and Saturn will seem exciting enough for the time being. Yet there are Uranus and Neptune to come. This group of scientific articles includes some of the first detailed attempts to make sense of last year's Voyager 1 observations of Saturn-and Nature acknowledges its debt to Dr G. E. Hunt of University College, London for having helped to recruit these articles and to give shape to the ground they cover. The scope is necessarily restricted, for there is hardly a branch of planetary astronomy which has not been changed in some way by the data from Voyager 1-and which is not about to be changed again.

  19. Triton - Voyager's finale

    NASA Technical Reports Server (NTRS)

    Brown, R. H.

    1992-01-01

    The investigation of the Neptunian satellite Triton by the Voyager 2 is described with interpretations of the object's nature and composition. The orbit, seasonal cycle, and southern-hemisphere solstice are described, and the composition of the satellite is discussed. Triton's mass and radius are known, and the objects is made up of about 70 percent rock and organics and 30 percent ice by mass. Triton's interior is warm and geologically active considering its distance from the sun, and large amounts of frozen methane and nitrogen are theorized to contribute to the object's high reflectivity. Also noted in the Voyager color images are creeping ice, cryogenic lava, and dark streaks on the south polar cap from nitrogen gas leaks driven by a type of greenhouse effect. Triton represents a class of satellite that has not been observed previously: a moon-sized body in a retrograde inclined orbit from the class of objects that coalesced to form Neptune.

  20. 46 CFR 185.503 - Voyage plan.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Voyage plan. 185.503 Section 185.503 Shipping COAST...) OPERATIONS Preparations for Emergencies § 185.503 Voyage plan. (a) The master of the following vessels shall prepare a voyage plan: (1) A vessel making an oceans or coastwise voyage; (2) A vessel making a voyage...

  1. Infrared spectrometer for Voyager.

    PubMed

    Hanel, R; Crosby, D; Herath, L; Vanous, D; Collins, D; Creswick, H; Harris, C; Rhodes, M

    1980-05-01

    The Voyager IR investigation uses a Michelson interferometer with a 4.3-cm(-1) spectral resolution in the 80-2500-cm(-1) range and a single-channel radiometer for the visible and near-IR, 5000-30,000-cm(-1). Both devices share a Cassegrain telescope with a 50-cm diam primary mirror and a 0.25 degrees field of view. Design, calibration, and performance are discussed along with a sample spectrum of Jupiter.

  2. The Voyager Interstellar Mission.

    PubMed

    Rudd, R P; Hall, J C; Spradlin, G L

    1997-01-01

    The Voyager Interstellar Mission began on January 1, 1990, with the primary objective being to characterize the interplanetary medium beyond Neptune and to search for the transition region between the interplanetary medium and the interstellar medium. At the start of this mission, the two Voyager spacecraft had already been in flight for over twelve years, having successfully returned a wealth of scientific information about the planetary systems of Jupiter, Saturn, Uranus, and Neptune, and the interplanetary medium between Earth and Neptune. The two spacecraft have the potential to continue returning science data until around the year 2020. With this extended operating lifetime, there is a high likelihood of one of the two spacecraft penetrating the termination shock and possibly the heliopause boundary, and entering interstellar space before that time. This paper describes the Voyager Interstellar Mission--the mission objectives, the spacecraft and science payload, the mission operations system used to support operations, and the mission operations strategy being used to maximize science data return even in the event of certain potential spacecraft subsystem failures. The implementation of automated analysis tools to offset and enable reduced flight team staffing levels is also discussed.

  3. The Voyager Interstellar Mission

    NASA Technical Reports Server (NTRS)

    Rudd, R. P.; Hall, J. C.; Spradlin, G. L.

    1997-01-01

    The Voyager Interstellar Mission began on January 1, 1990, with the primary objective being to characterize the interplanetary medium beyond Neptune and to search for the transition region between the interplanetary medium and the interstellar medium. At the start of this mission, the two Voyager spacecraft had already been in flight for over twelve years, having successfully returned a wealth of scientific information about the planetary systems of Jupiter, Saturn, Uranus, and Neptune, and the interplanetary medium between Earth and Neptune. The two spacecraft have the potential to continue returning science data until around the year 2020. With this extended operating lifetime, there is a high likelihood of one of the two spacecraft penetrating the termination shock and possibly the heliopause boundary, and entering interstellar space before that time. This paper describes the Voyager Interstellar Mission--the mission objectives, the spacecraft and science payload, the mission operations system used to support operations, and the mission operations strategy being used to maximize science data return even in the event of certain potential spacecraft subsystem failures. The implementation of automated analysis tools to offset and enable reduced flight team staffing levels is also discussed.

  4. Voyager Approaches Final Frontier

    NASA Technical Reports Server (NTRS)

    2003-01-01

    An artist's concept illustrates the positions of the Voyager spacecraft in relation to structures formed around our Sun by the solar wind. Also illustrated is the termination shock, a violent region the spacecraft must pass through before reaching the outer limits of the solar system. At the termination shock, the supersonic solar wind abruptly slows from an average speed of 400 kilometers per second to less than 100 kilometer per second (900,000 to less than 225,000 miles per hour). Beyond the termination shock is the solar system's final frontier, the heliosheath, a vast region where the turbulent and hot solar wind is compressed as it presses outward against the interstellar wind that is beyond the heliopause. A bow shock likely forms as the interstellar wind approaches and is deflected around the heliosphere, forcing it into a teardrop-shaped structure with a long, comet-like tail.

    The exact location of the termination shock is unknown, and it originally was thought to be closer to the Sun than Voyager 1 currently is. As Voyager 1 cruised ever farther from the Sun, it confirmed that all the planets are inside an immense bubble blown by the solar wind and the termination shock was much more distant.

  5. Voyager 1 'Blue Movie'

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This is the original Voyager 'Blue Movie' (so named because it was built from Blue filter images). It records the approach of Voyager 1 during a period of over 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storms shows how dynamic the Jovian atmosphere is.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  6. The Voyager Interstellar Mission.

    PubMed

    Rudd, R P; Hall, J C; Spradlin, G L

    1997-01-01

    The Voyager Interstellar Mission began on January 1, 1990, with the primary objective being to characterize the interplanetary medium beyond Neptune and to search for the transition region between the interplanetary medium and the interstellar medium. At the start of this mission, the two Voyager spacecraft had already been in flight for over twelve years, having successfully returned a wealth of scientific information about the planetary systems of Jupiter, Saturn, Uranus, and Neptune, and the interplanetary medium between Earth and Neptune. The two spacecraft have the potential to continue returning science data until around the year 2020. With this extended operating lifetime, there is a high likelihood of one of the two spacecraft penetrating the termination shock and possibly the heliopause boundary, and entering interstellar space before that time. This paper describes the Voyager Interstellar Mission--the mission objectives, the spacecraft and science payload, the mission operations system used to support operations, and the mission operations strategy being used to maximize science data return even in the event of certain potential spacecraft subsystem failures. The implementation of automated analysis tools to offset and enable reduced flight team staffing levels is also discussed. PMID:11540770

  7. Voyager 1 examines Jupiter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    An overview of the Voyager mission to Jupiter, Saturn, and possibly Uranus is presented. Scientific instruments onboard the spacecraft are described as well as methods used for their calibration and evaluation during the cruise phase of the mission. Experiments to be performed cover the following areas: imaging science, radio science, cosmic rays, ultraviolet spectroscopy, photopolarimetry, planetary radio astronomy, magnetic fields, low-energy charged particles, plasma science, and infrared radiometry and spectroscopy. A list of the satellites of Jupiter and their diameters, distances, and periods is included.

  8. Gigapan Voyage for Robotic Recon

    NASA Technical Reports Server (NTRS)

    Lee, Susan Y.; Moorse, Theodore Fitzgerald; Park, Eric J.

    2010-01-01

    Gigapan Voyage (GV) is a self-contained remotely-operable Gigapan capturing system that is currently being developed by the Intelligent Robotics Group (IRG) at NASA Ames Research Center. Gigapan Voyage was primarily designed to be integrated onto Johnson Space Center s Lunar Electric Rovers (LER). While on LER, Gigapan Voyage was used by scientists and astronauts during the 2009 and 2010 Desert RATS field tests. The concept behind Gigapan Voyage is to merge all the sub-components of the commercial GigaPan system into an all-in-one system that can capture, stitch, and display Gigapans in an automated way via a simple web interface. The GV system enables NASA to quickly and easily add remote-controlled Gigapan capturing capability onto rovers with minimal integration effort. Key Words: Geology, NASA, Black Point Lava Flow, Robot, K10, LER, Gigapan Voyage, Desert RATS, Intelligent Robotics Group

  9. 46 CFR 122.503 - Voyage plan.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST... Emergencies § 122.503 Voyage plan. (a) The master of the following vessels shall prepare a voyage plan: (1) A... United States Great Lakes port from a Canadian Great Lakes port. (b) The voyage plan required...

  10. 46 CFR Sec. 2 - Voyage numbers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... voyage No. 1 having the prefixed designation NSA and followed by the General Agents' abbreviated designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change with... General Agent shall affix his abbreviated designation and initial voyage numbers, as NSA-13/XYZ-1....

  11. 46 CFR Sec. 2 - Voyage numbers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... voyage No. 1 having the prefixed designation NSA and followed by the General Agents' abbreviated designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change with... General Agent shall affix his abbreviated designation and initial voyage numbers, as NSA-13/XYZ-1....

  12. 46 CFR Sec. 2 - Voyage numbers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... voyage No. 1 having the prefixed designation NSA and followed by the General Agents' abbreviated designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change with... General Agent shall affix his abbreviated designation and initial voyage numbers, as NSA-13/XYZ-1....

  13. 46 CFR Sec. 2 - Voyage numbers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... voyage No. 1 having the prefixed designation NSA and followed by the General Agents' abbreviated designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change with... General Agent shall affix his abbreviated designation and initial voyage numbers, as NSA-13/XYZ-1....

  14. 46 CFR Sec. 2 - Voyage numbers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... voyage No. 1 having the prefixed designation NSA and followed by the General Agents' abbreviated designation and voyage number, as NSA-1/ABC-1. (b) The continuity of NSA voyage numbers shall not change with... General Agent shall affix his abbreviated designation and initial voyage numbers, as NSA-13/XYZ-1....

  15. 46 CFR 122.503 - Voyage plan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST... Emergencies § 122.503 Voyage plan. (a) The master of the following vessels shall prepare a voyage plan: (1) A... United States Great Lakes port from a Canadian Great Lakes port. (b) The voyage plan required...

  16. 46 CFR Sec. 4 - Voyage terminations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Voyage terminations. Sec. 4 Section 4 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 4 Voyage terminations. (a) All voyages shall terminate at a continental United States port at 2400 hours of the date...

  17. 46 CFR Sec. 3 - Voyage commencements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Voyage commencements. Sec. 3 Section 3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 3 Voyage commencements. (a) All voyages shall commence at 0001 hours of the date on which any of the following...

  18. 46 CFR Sec. 4 - Voyage terminations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Voyage terminations. Sec. 4 Section 4 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 4 Voyage terminations. (a) All voyages shall terminate at a continental United States port at 2400 hours of the date...

  19. 46 CFR Sec. 4 - Voyage terminations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Voyage terminations. Sec. 4 Section 4 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 4 Voyage terminations. (a) All voyages shall terminate at a continental United States port at 2400 hours of the date...

  20. 46 CFR Sec. 4 - Voyage terminations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Voyage terminations. Sec. 4 Section 4 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 4 Voyage terminations. (a) All voyages shall terminate at a continental United States port at 2400 hours of the date...

  1. 46 CFR Sec. 4 - Voyage terminations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Voyage terminations. Sec. 4 Section 4 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 4 Voyage terminations. (a) All voyages shall terminate at a continental United States port at 2400 hours of the date...

  2. 46 CFR Sec. 3 - Voyage commencements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Voyage commencements. Sec. 3 Section 3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 3 Voyage commencements. (a) All voyages shall commence at 0001 hours of the date on which any of the following...

  3. 46 CFR Sec. 3 - Voyage commencements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Voyage commencements. Sec. 3 Section 3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 3 Voyage commencements. (a) All voyages shall commence at 0001 hours of the date on which any of the following...

  4. 46 CFR Sec. 3 - Voyage commencements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Voyage commencements. Sec. 3 Section 3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 3 Voyage commencements. (a) All voyages shall commence at 0001 hours of the date on which any of the following...

  5. 46 CFR Sec. 3 - Voyage commencements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Voyage commencements. Sec. 3 Section 3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY VOYAGE DATA Sec. 3 Voyage commencements. (a) All voyages shall commence at 0001 hours of the date on which any of the following...

  6. Voyager photometry of Europa

    NASA Technical Reports Server (NTRS)

    Buratti, B.; Veverka, J.

    1983-01-01

    The photometric properties of Europa are derived through an analysis of 90 Voyager images with 3-143 deg phase angles in the spectral range from 0.34 to 0.58 microns. It is noted that, at small phase angles, the disk-integrated phase curve shows almost no evidence of an opposition effect. The scattering properties of Europa in general, and of the bright plain and dark mottled terrain types, cannot be represented by a lunar-like photometric law, although an equation which is a linear superposition of a lunar-like scattering law and a Lambert component provides an adequate and simple representation of scattering properties. The plains are photometrically more homogeneous than the mottled terrain, and these two terrain types exhibit an average normal reflectance of 0.71 on both leading and trailing hemispheres and of 0.60 on leading and 0.48 on trailing hemispheres, respectively.

  7. Jupiter and the Voyager mission

    USGS Publications Warehouse

    Soderblom, L.; Spall, Henry

    1980-01-01

    In 1977, the United States launched two unmanned Voyager spacecraft that were to take part in an extensive reconnaissance of the outer planets over a 12-year period visiting the environs of Jupiter, Saturn, Uranus, and Neptune. Their first encounter was with the complex Jupiter planetary system 400 million miles away. Sweeping by Jupiter and its five moons in 1979, the two spacecraft have sent back to Earth an enormous amount of data that will prove to be vital in understanding our solar system. Voyager 1 is scheduled to fly past Saturn on November 13 of this year; Voyager 2, in August of the following year. 

  8. Voyager Encounters Saturn: Scientific Highlights

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Observations generated by Voyager 1's encounter with Saturn are disclosed. Atmospheric conditions, the rings, new moons and the five inner moons are described. Titan, Hyperion and Iapetus are discussed in detail, as is Saturn's magnetosphere.

  9. Planetary radio astronomy from Voyager

    NASA Technical Reports Server (NTRS)

    Alexander, J. K.

    1983-01-01

    The technique of radio astronomy makes it possible for a remote observer to detect the presence of magnetic fields and plasmas in planetary environments. Prior to the flights of the Voyager spacecraft, radio astronomical studies of Jupiter from earth and from earth orbit had correctly predicted the strength and orientation of Jupiter's magnetic field and trapped radiation belts. The Voyager Planetary Radio Astronomy investigations have now provided measurements of the complete spectrum of low frequency radio emissions from both planets. Each Voyager instrument consists of a pair of orthogonal, 10-m, electric monopole antennas which are connected to a step-tuned, superheterodyne receiver operating over the frequency range from 1.2 kHz to 40.5 MHz. The Voyager trajectory provided observations from above both the sunlit and nightside hemispheres of Jupiter. Saturn's nonthermal radio emission has been observed at frequencies as low as 3 kHz and as high as 1.2 MHz.

  10. The Voyager 2 Neptune encounter

    SciTech Connect

    Tsurutani, B.T. )

    1989-10-01

    The findings made by the Voyager 2 Neptune encounter are reviewed. Data on the bowshock, magnetic field, magnetosphere, rings, plasma sheet, aurora, moons, and dust of Neptune are discussed. Findings made concerning Triton are summarized.

  11. Voyager to the Seventh Planet.

    ERIC Educational Resources Information Center

    Gold, Michael

    1986-01-01

    Presents recent findings obtained by the Voyager 2 mission on Uranus. Updates information on the planet's moons, rings, atmosphere, and magnetic field. Illustrations and diagrams of selected aspects of Uranus are included. (ML)

  12. Triumph of the Voyager mission

    USGS Publications Warehouse

    Kerr, R. A.

    1989-01-01

    It had been a long, productive trip. Launched in 1977, the two Voyager spacecraft had visited three giant planets, a dozen major Moons, three ring systems with thousands of rings composed of a myriad of tiny Moonlets. The spacecraft had returned 5 trillion bits of data and over 100,000 photographs. The last encounter in our Solar System by Voyager 2 with Neptune was to be a spectacular finale to the 12-year drama. 

  13. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  14. Solar System Voyage

    NASA Astrophysics Data System (ADS)

    Brunier, Serge

    2002-11-01

    In the last few decades, the exploration of our solar system has revealed fascinating details about the worlds that lie beyond our Earth. This lavishly illustrated book invites the reader on a journey through the solar system. After locating our planetary system in the Universe, Brunier describes the Sun and its planets, the large satellites, asteroids, and comets. Photographs and information taken from the latest space missions allow readers to experience spectacular scenes: the lunar plains scarred by asteroid impacts, the frozen deserts of Mars and Europa, the continuously erupting volcanoes of Io and the giant geysers of Triton, the rings of Saturn and the clouds of Venus and Titan, and the powerful crash of the comet Shoemaker-Levy into Jupiter. Inspired by the extraordinary photographs and incisive text, readers of Solar System Voyage will gain a greater appreciation of the hospitable planet we call home. Serge Brunier is chief editor of the journal Ciel et Espace, a photojournalist, and the author of many nonfiction books aimed at both specialists and the general public. His previous books include Space Odyssey (Cambridge, 2002), Glorious Eclipses with Jean-Pierre Luminet (Cambridge, 2000), and Majestic Universe (Cambridge, 1999).

  15. NASA's Arctic Voyage 2010

    NASA Video Gallery

    NASA's first oceanographic research expedition left Alaska on June 15, 2010. The ICESCAPE mission will head into the Arctic to study sea ice and the changing ocean ecosystem. Listen to the scientis...

  16. Voyager spacecraft images of Jupiter and Saturn.

    PubMed

    Birnbaum, M M

    1982-01-15

    The images of Jupiter and Saturn and their satellites taken by the Voyager spacecraft TV cameras are shown and described. The scientific findings of the Voyager mission instruments and experiments are summarized.

  17. The Voyager Neptune travel guide

    NASA Technical Reports Server (NTRS)

    Kohlhase, Charles (Editor)

    1989-01-01

    The Voyager mission to the giant outer planets of our solar system is described. Scientific highlights include interplanetary cruise, Jupiter, Saturn, Uranus, and their vast satellite and ring systems. Detailed plans are provided for the August 1989 Neptune encounter and subsequent interstellar journey to reach the heliopause. As background, the elements of an unmanned space mission are explained, with emphasis on the capabilities of the spacecraft and the scientific sensors. Other topics include the Voyager Grand Tour trajectory design, deep-space navigation, and gravity-assist concepts. The Neptune flyby is animated through the use of computer-generated, flip-page movie frames that appear in the corners of the publication. Useful historical information is also presented, including facts associated with the Voyager mission. Finally, short summaries are provided to describe the major objectives and schedules for several space missions planned for the remainder of the 20th century.

  18. 46 CFR 80.15 - Ocean voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD... REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body of water seaward of the low water mark such as an ocean or arm thereof, other major bodies of water such...

  19. 46 CFR 80.15 - Ocean voyage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD... REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body of water seaward of the low water mark such as an ocean or arm thereof, other major bodies of water such...

  20. 46 CFR 80.15 - Ocean voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD... REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body of water seaward of the low water mark such as an ocean or arm thereof, other major bodies of water such...

  1. 46 CFR 80.15 - Ocean voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD... REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body of water seaward of the low water mark such as an ocean or arm thereof, other major bodies of water such...

  2. 46 CFR 80.15 - Ocean voyage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Ocean voyage. 80.15 Section 80.15 Shipping COAST GUARD... REGISTRY § 80.15 Ocean voyage. An ocean voyage for the purposes of this part means: A voyage on any body of water seaward of the low water mark such as an ocean or arm thereof, other major bodies of water such...

  3. Jupiter - First stop on Voyager's grand tour

    NASA Technical Reports Server (NTRS)

    Morrison, David

    1989-01-01

    The findings concerning Jupiter that were made by the Voyager missions are briefly reviewed. The ring and three new moons around Jupiter, the live volcanoes on Io, and atmospheric phenomena on Jupiter which were observed by Voyager 1 are described. The discoveries regarding Callisto and Europa made by Voyager 2 are briefly summarized.

  4. Science at Sea.

    ERIC Educational Resources Information Center

    Phillips, Mary Nied

    2001-01-01

    Describes a three-week inservice teacher education program that involves two sessions of preparatory classes ashore in nautical science and oceanography, and concludes with a nine-day sea voyage. (ASK)

  5. Technology Brings Voyagers into Classrooms.

    ERIC Educational Resources Information Center

    Inn, Kristina; And Others

    1995-01-01

    Three articles focus on many classroom activities and experiments inspired by the voyage of two canoes, built of traditional materials, from Hawaii's Hilo Harbor in 1995. Nationwide, students followed daily satellite tracking, accessed the Internet for updated accounts of the canoes, talked directly with navigators, and watched television…

  6. The Voyage of the MIMI.

    ERIC Educational Resources Information Center

    Gibbon, Sam; Hooper, Kristina

    1986-01-01

    The Voyage of MIMI is a major educational project housed at Bank Street College (New York) which is directed toward the development of extensive television, computer software, videodisc, and print materials for use in science and mathematics education in grades 5-7. The first series has been completed, and includes a 13-part dramatic television…

  7. Voyager - a mission for life

    NASA Astrophysics Data System (ADS)

    Williamson, Mark

    2012-12-01

    There may be no such thing as a "job for life" these days, but NASA's Voyager mission to Jupiter, Saturn and beyond has kept hundreds of scientists busy for as much as 35 years. Mark Williamson reveals how researchers stay motivated and scientifically productive during such a long-term project.

  8. "Voyager": An Educational Card Game

    ERIC Educational Resources Information Center

    Smith, David Ryan

    2003-01-01

    "Voyager" is an educational card game involving scientific satellites, developed for use in schools with children aged 9 to 13 years. The idea of the game is to improve pupils' knowledge about the large number of scientific satellites there are in space in a fun way, while also practising numeracy skills. Several copies of the game were produced…

  9. Voyager to Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The NASA Voyager mission to explore planets of the outer solar system is summarized. The mission schedule and profiles for encounters with Jupiter and Saturn, and possibly with Uranus and Pluto are included along with a description of the spacecraft and its trajectories. Scientific investigations to be made and the instruments carried are also discussed.

  10. Voyager program. Voyager 1 encounter at Jupiter, 5 March 1979

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Highlights of Voyager 1 activity during the observatory and far-encounter phases are summarized. Daily sequence of events for the spacecraft during the period of greatest encounter activity (Feb. 26 through Mar. 7) the near-encounter phase is given. Times shown designate the time of signal reception at Deep Space Network stations. Events listed emphasize activities pertaining to the four remote sensing instruments on the scan platforms. However, the other 7 experiments will continuously collect data throughout the encounter period.

  11. The Voyager program at APL

    SciTech Connect

    Mauk, B.H.; Keath, E.P.; Krimigis, S.M. )

    1990-06-01

    An overview is presented of the structure and function of the Applied Physics Laboratory's low-energy charged particle (LECP) instrument used in NASA's Voyager program. The LECP experiment was designed to measure the intensity, energy spectra, composition, angular distributions, and spatial and temporal characteristics of ions and electrons that are encountered by the spacecraft. Scientific findings of previous planetary encounters are noted, and color energy-time spectrograms that summarize the LECP results at each planet are presented and analyzed. Some details of the encounter by Voyager 2 of Neptune are provided, noting that the characteristics of the trajectory that was used provided for close observation of Triton, observations of particle structures, and exploration of Neptune's polar cap. A schematic of Neptune's magnetosphere is provided and analyzed. 11 refs.

  12. Ariel at Voyager Closest Approach

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This picture is part of the highest-resolution Voyager 2 imaging sequence of Ariel, a moon of Uranus about 1,300 kilometers (800 miles) in diameter. The clear-filter, narrow-angle image was taken Jan. 24, 1986, from a distance of 130,000 km (80,000 mi). The complexity of Ariel's surface indicates that a variety of geologic processes have occurred. The numerous craters, for example, are indications of an old surface bombarded by meteoroids over a long period. Also conspicuous at this resolution, about 2.4 km (1.5 mi), are linear grooves (evidence of tectonic activity that has broken up the surface) and smooth patches (indicative of deposition of material). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.

  13. Voyager to the giant planets

    NASA Astrophysics Data System (ADS)

    Smith, B. A.

    The exploration of Jupiter and Saturn by the Pioneer and Voyager probes is reviewed chronologically. Consideration is given to the launching techniques and probe designs; the complex convection patterns in the Jovian atmosphere; the lightning and auroras seen on Jupiter's dark side; the faint Jovian ring; the surfaces of Ganymede, Callisto, and Europa; and the discovery of volcanic activity on Io. The features of Saturn discussed include the earth-like atmospheric jets, the surface and atmosphere of Titan, the orbits of the other satellites, the surface characteristics of Iapetus and Enceladus, the 10,000 ringlets comprising the ring system, the apparent 'spokes' in the rings, and the narrow, knotted F ring. Voyager images of the most significant features are provided.

  14. Take a Voyage of Discovery

    ERIC Educational Resources Information Center

    Texley, Juliana

    2008-01-01

    On December 27, 1831, the "H.M.S. Beagle" left Plymouth Harbor for a round-the-world voyage. On board was would-be botanist Charles Darwin, the best tour guide biology has ever known. In 2009, we will celebrate Darwin's 200th birthday and the 150th anniversary of "The Origin of Species" publication. What better way to prepare for this celebration…

  15. Voyager 1: Encounter with Saturn

    NASA Technical Reports Server (NTRS)

    Panagakos, N.

    1980-01-01

    The history of the Voyager Project is reviewed as well as known facts about Saturn and its satellites. Important results of encounters with Jupiter are summarized. Scientific objectives of the flyby of Saturn involve the planet's atmosphere, rings, and magnetic field interactions with the solar wind and satellites. The search for additional satellites, and various aspects of Titan, Rhea, Dione, Mimas, Iapetus, Hyperion, and Enceladas are also of interest. The instruments developed to obtain these goals are described.

  16. VOYAGER 1 NEAR THE HELIOPAUSE

    SciTech Connect

    Borovikov, S. N.; Pogorelov, N. V.

    2014-03-01

    Recent observations from the Voyager 1 spacecraft show that it is sampling the local interstellar medium (LISM). This is quite surprising because no realistic, steady-state model of the solar wind (SW) interaction with the LISM gives an inner heliosheath width as narrow as ∼30 AU. This includes models that assume a strong redistribution of the ion energy to the tails in the pickup ion distribution function. We show that the heliopause (HP), which separates the SW from the LISM, is not a smooth tangential discontinuity, but rather a surface subject to Rayleigh-Taylor-type instabilities which can result in LISM material penetration deep inside the SW. We also show that the HP flanks are always subject to a Kelvin-Helmholtz instability. The instabilities are considerably suppressed near the HP nose by the heliospheric magnetic field in steady-state models, but reveal themselves in the presence of solar cycle effects. We argue that Voyager 1 may be in one such instability region and is therefore observing plasma densities much higher than those in the pristine SW. These results may explain the early penetration of Voyager 1 into the LISM. They also show that there is a possibility that the spacecraft may start sampling the SW again before it finally leaves the heliosphere.

  17. Voyager 1 View of Callisto

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Voyager 1 took this picture of Callisto during Voyager's approach to Jupiter's outer large satellite in 1979. Both Galileo and Marius discovered Callisto in 1610. In Greek mythology, Callisto was a nymph loved by Zeus and thus hated by Hera. Hera turned her into a bear, which Zeus placed in the heavens as the constellation Ursa Major. Voyager was 350,000 kilometers from Callisto and took this picture that shows features about seven kilometers wide across the surface. Callisto is a little smaller than Ganymede (Callisto is about the size of Mercury) and it seems that it is composed of a mixture of ice and rock (about 40 percent ice and 60 percent rock and iron). The darker color of Callisto (about half as reflective as Ganymede but still twice as bright as the Moon) implies that the upper surface is 'dirty ice' or water- rich rock frozen on Callisto's cold surface (approximately -243 Fahrenheit degrees at the equator). Callisto's atmosphere is mostly carbon dioxide. Far more craters appear on the surface of Callisto than on the surface of Ganymede, leading scientists to believe that Callisto is the oldest of the Galilean satellites. Callisto could date back as far as four billion years ago and has remained relatively unchanged in the history of space.

  18. Voyager 1 Image of Ganymede

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Voyager 1 took this picture of Ganymede from a distance of 1.6 million miles. Ganymede is Jupiter's largest satellite with a radius of approximately 2600 kilometers, about 1.5 times that of Earth's Moon. Ganymede is the seventh and largest of Jupiter's known satellites and is the third of the Galilean moons. Discovered in 1610 by Galileo and Marius, Ganymede is the largest satellite in the Solar System. It was named after the Greek mythical character, Ganymede, a handsome Trojan boy that Zeus took to Olympus to be a cupbearer for the gods (one of the only humans in Greek mythology who became immortal). Ganymede is larger than Mercury but has only half Mercury's mass. It has a bulk density of only two grams per cubic centimeter, almost half that of Earth's Moon. Ganymede is most likely composed of a mixture of rock and ice. The long white filaments resemble rays associated with impacts on the lunar surface. The various colors of different regions probably represent differing surface materials. Several dots of a single color (blue, green, and orange) on the picture are the result of markings on the camera used for pointing determinations and are not physical markings. Voyager scientists discovered that Ganymede has its own magnetosphere embedded inside Jupiter's large one. JPL manages and controls the Voyager Project for NASA's Office of Space Science.

  19. 46 CFR 30.01-6 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Convention for Safety of Life at Sea, 1974 (SOLAS 74) applies, to a port outside that country or the reverse... States, and all lands held by the United States under a protectorate or mandate, whose international... nautical miles from the nearest land in the course of its voyage....

  20. 46 CFR 70.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the International Convention for Safety of Life at Sea, 1974, (SOLAS 74) applies, to a port outside... possessions of the United States and all lands held by the United States under a protectorate or mandate... nautical miles from the nearest land in the course of its voyage....

  1. Astrographic Observations of Pheobe from Voyager 2

    NASA Technical Reports Server (NTRS)

    Jacobson, R. A.

    1996-01-01

    This article provides the reduced astrographic observations of the ninth Saturnian satellite, Pheobe, derived from star-satellite imaging data acquired by the Voyager 2 spacecraft. The data set contains 8 pairs of spacecraft-centered right ascension and declination observations and includes all of the observations used in Voyager encounter operations.

  2. Voyager 2 encounter with the jovian system.

    PubMed

    Stone, E C; Lane, A L

    1979-11-23

    An overview of the Voyager 2 encounter with Jupiter is presented, including a brief discussion of the trajectory, the major sequence modifications performed because of the Jupiter measurements obtained with Voyager 1, and high-lights of the results that are described in the subsequent reports.

  3. 46 CFR 185.503 - Voyage plan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Voyage plan. 185.503 Section 185.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.503 Voyage plan. (a) The master of the following vessels...

  4. 46 CFR 185.503 - Voyage plan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Voyage plan. 185.503 Section 185.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.503 Voyage plan. (a) The master of the following vessels...

  5. 46 CFR 185.503 - Voyage plan.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Voyage plan. 185.503 Section 185.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.503 Voyage plan. (a) The master of the following vessels...

  6. 46 CFR 185.503 - Voyage plan.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Voyage plan. 185.503 Section 185.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) OPERATIONS Preparations for Emergencies § 185.503 Voyage plan. (a) The master of the following vessels...

  7. Voyager Sails into Market for Reading

    ERIC Educational Resources Information Center

    Manzo, Kathleen Kennedy

    2006-01-01

    This article reports how the Voyager Universal Literacy core program, which is sailing successively into the market for reading programs, has been the target of several speculations over its secrets of success. Use of the Voyager Universal Literacy program has since spread to 1,000 districts throughout the country since its introduction into the…

  8. Voyager at Neptune - A preliminary report

    SciTech Connect

    Kaufmann, W.J. Illinois Univ., Urbana )

    1989-12-01

    Data obtained from the Voyager mission to Neptune are discussed. The atmosphere and magnetosphere of Neptune are described. Specific attention is given to Neptune's Great Dark Spot and its systems of thin, dark rings. The Voyager data regarding Neptune's satellites, in particular Triton and Nereid, are examined.

  9. Voyager 2 to make closest encounter with Saturn in August

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The planned Voyager 2 Saturn mission is described. Information about Saturn obtained from the Voyager 1 encounter is summarized. Data on the satellites and rings of Saturn are tabulated. The video programming schedule for the Voyager 2 Saturn encounter is given. The Voyager science team is listed.

  10. 46 CFR 42.05-45 - International voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false International voyage. 42.05-45 Section 42.05-45 Shipping... Definition of Terms Used in This Subchapter § 42.05-45 International voyage. (a) The term international voyage as used in this part shall have the same meaning as the term international voyage in Article...

  11. 46 CFR 42.05-45 - International voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false International voyage. 42.05-45 Section 42.05-45 Shipping... Definition of Terms Used in This Subchapter § 42.05-45 International voyage. (a) The term international voyage as used in this part shall have the same meaning as the term international voyage in Article...

  12. 46 CFR 42.05-45 - International voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false International voyage. 42.05-45 Section 42.05-45 Shipping... Definition of Terms Used in This Subchapter § 42.05-45 International voyage. (a) The term international voyage as used in this part shall have the same meaning as the term international voyage in Article...

  13. 46 CFR 42.05-45 - International voyage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false International voyage. 42.05-45 Section 42.05-45 Shipping... Definition of Terms Used in This Subchapter § 42.05-45 International voyage. (a) The term international voyage as used in this part shall have the same meaning as the term international voyage in Article...

  14. Voyager 1 Red Spot Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This movie shows the portion of Jupiter around the Great Red Spot as it swirls through more than 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storm shows how dynamic the Jovian atmosphere is.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  15. Voyager 2 Jupiter Eruption Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This movie records an eruptive event in the southern hemisphere of Jupiter over a period of 8 Jupiter days. Prior to the event, an undistinguished oval cloud mass cruised through the turbulent atmosphere. The eruption occurs over avery short time at the very center of the cloud. The white eruptive material is swirled about by the internal wind patterns of the cloud. As a result of the eruption, the cloud then becomes a type of feature seen elsewhere on Jupiter known as 'spaghetti bowls'.

    As Voyager 2 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 8 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Violet filter around May 6, 1979. The spacecraft was about 50 million kilometers from Jupiter at that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  16. The Argonne Voyager multimedia server

    SciTech Connect

    Disz, T.; Judson, I.; Olson, R.; Stevens, R.

    1997-07-01

    With the growing presence of multimedia-enabled systems, one will see an integration of collaborative computing concepts into the everyday environments of future scientific and technical workplaces. Desktop teleconferencing is in common use today, while more complex desktop teleconferencing technology that relies on the availability of multipoint (greater than two nodes) enabled tools is now starting to become available on PCs. A critical problem when using these collaboration tools is the inability to easily archive multistream, multipoint meetings and make the content available to others. Ideally one would like the ability to capture, record, playback, index, annotate and distribute multimedia stream data as easily as one currently handles text or still image data. While the ultimate goal is still some years away, the Argonne Voyager project is aimed at exploring and developing media server technology needed to provide a flexible virtual multipoint recording/playback capability. In this article the authors describe the motivating requirements, architecture implementation, operation, performance, and related work.

  17. Voyages Through Time: Everything Evolves

    NASA Astrophysics Data System (ADS)

    Pendleton, Y. J.; Tarter, J. C.; DeVore, E. K.; O'Sullivan, K. A.; Taylor, S. M.

    2001-12-01

    Evolutionary change is a powerful framework for studying our world and our place therein. It is a recurring theme in every realm of science: over time, the universe, the planet Earth, life, and human technologies all change, albeit on vastly different scales. Evolution offers scientific explanations for the age-old question, "Where did we come from?" In addition, historical perspectives of science show how our understanding has evolved over time. The complexities of all of these systems will never reveal a "finished" story. But it is a story of epic size, capable of inspiring awe and of expanding our sense of time and place, and eminently worthy of investigating. This story is the basis of Voyages Through Time. Voyages Through Time (VTT), provides teachers with not only background science content and pedagogy, but also with materials and resources for the teaching of evolution. The six modules, Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, Hominid Evolution, and Evolution of Technology, emphasize student inquiry, and promote the nature of science, as recommended in the NSES and BSL. The modules are unified by the overarching theme of evolution and the meta questions: "What is changing?" "What is the rate of change?" and "What is the mechanism of change?" Determination of student outcomes for the project required effective collaboration of scientists, teachers, students and media specialists. The broadest curricula students outcomes are 1) an enjoyment of science, 2) an understanding of the nature of science, especially the understanding of evidence and re-evaluation, and 3) key science content. The curriculum is being developed by the SETI Institute, NASA Ames Research Center, California Academy of Sciences, and San Francisco State University, and is funded by the NSF (IMD 9730693), with support form Hewlett-Packard Company, The Foundation for Microbiology, Combined Federated Charities, NASA Astrobiology Institute, and NASA Fundamental

  18. Climate windows for Polynesian voyaging to New Zealand and Easter Island.

    PubMed

    Goodwin, Ian D; Browning, Stuart A; Anderson, Atholl J

    2014-10-14

    Debate about initial human migration across the immense area of East Polynesia has focused upon seafaring technology, both of navigation and canoe capabilities, while temporal variation in sailing conditions, notably through climate change, has received less attention. One model of Polynesian voyaging observes that as tradewind easterlies are currently dominant in the central Pacific, prehistoric colonization canoes voyaging eastward to and through central East Polynesia (CEP: Society, Tuamotu, Marquesas, Gambier, Southern Cook, and Austral Islands) and to Easter Island probably had a windward capacity. Similar arguments have been applied to voyaging from CEP to New Zealand against prevailing westerlies. An alternative view is that migration required reliable off-wind sailing routes. We investigate the marine climate and potential voyaging routes during the Medieval Climate Anomaly (MCA), A.D. 800-1300, when the initial colonization of CEP and New Zealand occurred. Paleoclimate data assimilation is used to reconstruct Pacific sea level pressure and wind field patterns at bidecadal resolution during the MCA. We argue here that changing wind field patterns associated with the MCA provided conditions in which voyaging to and from the most isolated East Polynesian islands, New Zealand, and Easter Island was readily possible by off-wind sailing. The intensification and poleward expansion of the Pacific subtropical anticyclone culminating in A.D. 1140-1260 opened an anomalous climate window for off-wind sailing routes to New Zealand from the Southern Austral Islands, the Southern Cook Islands, and Tonga/Fiji Islands.

  19. Climate windows for Polynesian voyaging to New Zealand and Easter Island.

    PubMed

    Goodwin, Ian D; Browning, Stuart A; Anderson, Atholl J

    2014-10-14

    Debate about initial human migration across the immense area of East Polynesia has focused upon seafaring technology, both of navigation and canoe capabilities, while temporal variation in sailing conditions, notably through climate change, has received less attention. One model of Polynesian voyaging observes that as tradewind easterlies are currently dominant in the central Pacific, prehistoric colonization canoes voyaging eastward to and through central East Polynesia (CEP: Society, Tuamotu, Marquesas, Gambier, Southern Cook, and Austral Islands) and to Easter Island probably had a windward capacity. Similar arguments have been applied to voyaging from CEP to New Zealand against prevailing westerlies. An alternative view is that migration required reliable off-wind sailing routes. We investigate the marine climate and potential voyaging routes during the Medieval Climate Anomaly (MCA), A.D. 800-1300, when the initial colonization of CEP and New Zealand occurred. Paleoclimate data assimilation is used to reconstruct Pacific sea level pressure and wind field patterns at bidecadal resolution during the MCA. We argue here that changing wind field patterns associated with the MCA provided conditions in which voyaging to and from the most isolated East Polynesian islands, New Zealand, and Easter Island was readily possible by off-wind sailing. The intensification and poleward expansion of the Pacific subtropical anticyclone culminating in A.D. 1140-1260 opened an anomalous climate window for off-wind sailing routes to New Zealand from the Southern Austral Islands, the Southern Cook Islands, and Tonga/Fiji Islands. PMID:25267611

  20. Climate windows for Polynesian voyaging to New Zealand and Easter Island

    PubMed Central

    Goodwin, Ian D.; Browning, Stuart A.; Anderson, Atholl J.

    2014-01-01

    Debate about initial human migration across the immense area of East Polynesia has focused upon seafaring technology, both of navigation and canoe capabilities, while temporal variation in sailing conditions, notably through climate change, has received less attention. One model of Polynesian voyaging observes that as tradewind easterlies are currently dominant in the central Pacific, prehistoric colonization canoes voyaging eastward to and through central East Polynesia (CEP: Society, Tuamotu, Marquesas, Gambier, Southern Cook, and Austral Islands) and to Easter Island probably had a windward capacity. Similar arguments have been applied to voyaging from CEP to New Zealand against prevailing westerlies. An alternative view is that migration required reliable off-wind sailing routes. We investigate the marine climate and potential voyaging routes during the Medieval Climate Anomaly (MCA), A.D. 800–1300, when the initial colonization of CEP and New Zealand occurred. Paleoclimate data assimilation is used to reconstruct Pacific sea level pressure and wind field patterns at bidecadal resolution during the MCA. We argue here that changing wind field patterns associated with the MCA provided conditions in which voyaging to and from the most isolated East Polynesian islands, New Zealand, and Easter Island was readily possible by off-wind sailing. The intensification and poleward expansion of the Pacific subtropical anticyclone culminating in A.D. 1140–1260 opened an anomalous climate window for off-wind sailing routes to New Zealand from the Southern Austral Islands, the Southern Cook Islands, and Tonga/Fiji Islands. PMID:25267611

  1. Voyager 1 encounter with the jovian system.

    PubMed

    Stone, E C; Lane, A L

    1979-06-01

    An overview of the Voyager 1 encounter with Jupiter is presented, including a brief discussion of the characteristics of the spacecraft and trajectory and highlights of the results which are described in the subsequent reports.

  2. Voyager 2 encounter with the saturnian system.

    PubMed

    Stone, E C; Miner, E D

    1982-01-29

    An overview of the Voyager 2 encounter with Saturn is presented, including a brief discussion of the trajectory, the planned observations, and highlights of the results described in the subsequent reports.

  3. Voyager 1 encounter with the saturnian system.

    PubMed

    Stone, E C; Miner, E D

    1981-04-10

    An overview of the Voyager 1 encounter with Saturn is presented, including a brief discussion of the flight, trajectory, science plan formulation, and highlights of the results described in the subsequent reports.

  4. Voyager: Perils of advanced planning, 1960 - 1967

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Contract proposals; phased project planning; budgetary problems; Saturn 1 B-Centaur versus Saturn V; mission guidelines and management assignments; and the origins of the Voyager project are discussed.

  5. Voyager 1 Explores the "Magnetic Highway"

    NASA Video Gallery

    This set of animations show NASA's Voyager 1 spacecraft exploring a new region in our solar system called the "magnetic highway." In this region, the sun's magnetic field lines are connected to int...

  6. Voyager Observations in the Heliosheath and Beyond

    NASA Astrophysics Data System (ADS)

    Stone, E. C.

    2016-07-01

    Now at ˜136 AU, Voyager 1 has been observing the intensity, composition, pitch-angle anisotropies, and transient perturbations of the local interstellar galactic cosmic rays over the last four years. During this time, Voyager 2 has continued to observe the spectral evolution of anomalous cosmic rays and the solar modulation of galactic cosmic rays in the heliosheath and is now at ˜112 AU. An overview and update of these and other observations will be presented.

  7. Voyager 2 and the Uranian rings

    SciTech Connect

    Porco, C.C.

    1986-12-01

    Voyager 2 data on the Uranian disk system are presented and examined. The disk system consists of nine narrow rings, ranging in width from a few km to about 100 km. The Uranian rings are eccentric, inclined to the planet's equatorial plane, and precessing. The Uranian ring characteristics detected in the Voyager data are described and compared with those of the Saturn rings. The origin and maintenance of the rings are discussed, and the particle distribution in the ring system is studied.

  8. Ancient Voyaging and Polynesian Origins

    PubMed Central

    Soares, Pedro; Rito, Teresa; Trejaut, Jean; Mormina, Maru; Hill, Catherine; Tinkler-Hundal, Emma; Braid, Michelle; Clarke, Douglas J.; Loo, Jun-Hun; Thomson, Noel; Denham, Tim; Donohue, Mark; Macaulay, Vincent; Lin, Marie; Oppenheimer, Stephen; Richards, Martin B.

    2011-01-01

    The “Polynesian motif” defines a lineage of human mtDNA that is restricted to Austronesian-speaking populations and is almost fixed in Polynesians. It is widely thought to support a rapid dispersal of maternal lineages from Taiwan ∼4000 years ago (4 ka), but the chronological resolution of existing control-region data is poor, and an East Indonesian origin has also been proposed. By analyzing 157 complete mtDNA genomes, we show that the motif itself most likely originated >6 ka in the vicinity of the Bismarck Archipelago, and its immediate ancestor is >8 ka old and virtually restricted to Near Oceania. This indicates that Polynesian maternal lineages from Island Southeast Asia gained a foothold in Near Oceania much earlier than dispersal from either Taiwan or Indonesia 3–4 ka would predict. However, we find evidence in minor lineages for more recent two-way maternal gene flow between Island Southeast Asia and Near Oceania, likely reflecting movements along a “voyaging corridor” between them, as previously proposed on archaeological grounds. Small-scale mid-Holocene movements from Island Southeast Asia likely transmitted Austronesian languages to the long-established Southeast Asian colonies in the Bismarcks carrying the Polynesian motif, perhaps also providing the impetus for the expansion into Polynesia. PMID:21295281

  9. Voyages Through Time: Everything Evolves

    NASA Astrophysics Data System (ADS)

    Fisher, Jane; Tarter, Jill; Devore, Edna; Pendleton, Yvonne; O'Sullivan, Kathleen; Burke, Meg

    2004-06-01

    The SETI Institute, the California Academy of Sciences, NASA Ames Research Center, and San Francisco State University have developed standards-based curriculum materials for a one-year high school integrated science course centered on the unifying theme of evolution. Scientists, teachers, curriculum writers, and media specialists are currently finalizing six modules that integrate astronomical, geological, and biological sciences as well as the history of science and technology. The sequence of lessons in each module is designed to promote students' understanding and skills as defined by the National Science Education Standards and Benchmarks for Science Literacy. The modules cover: Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, Hominid Evolution, and the Evolution of Technology. The core lessons for all six modules are provided via CD-ROM, including instructional guidelines, science background information, and additional resources (print, audiovisual, software, WWW sites, and databases). These products will be published as a complete set for use as a yearlong science course and will also be available as individual modules for use in discipline-based courses. Evolutionary change is a powerful framework for studying our world and our place therein. It is a story of epic size, capable of inspiring awe and of expanding our sense of time and place. This story is the basis of Voyages Through Time.

  10. Voyages Through Time: Everything Evolves

    NASA Astrophysics Data System (ADS)

    Tarter, Jill; Pendleton, Y.; DeVore, E.; O'Sullivan, K.; Taylor, S.

    The SETI Institute, the California Academy of Sciences, and NASA Ames Research Center are developing standards-based curriculum materials for a one-year high school science course centered on the unifying theme of evolution. Scientists, teachers, curriculum writers, and media specialists are currently developing six modules that integrate astronomical, geological, and biological sciences as well as the history of science and technology. The sequence of lessons in each module will be designed to promote students' understanding and skills as defined by the National Science Education Standards and Benchmarks for Science Literacy. The modules cover: Cosmic Evolution, Planetary Evolution, Origin of Life, Diversification of Life, Hominid Evolution, and the Evolution of Technology. The core lessons for all six modules will be provided via CD-ROM, including instructional guidelines, science background information, and additional resources (print, audiovisual, software, WWW sites, databases, and telecommunications projects). These products will be published as a complete set for use as a year-long science course and will also be available as individual modules for use in discipline-based courses. Evolutionary change is a powerful framework for studying our world and our place therein. It is a story of epic size, capable of inspiring awe and of expanding our sense of time and place. This story is the basis of Voyages Through Time.

  11. Voyager planetary radio astronomy studies

    NASA Technical Reports Server (NTRS)

    Staelin, David H.; Eikenberry, Stephen S.

    1993-01-01

    Analysis of nonthermal radio emission data obtained by the Planetary Radio Astronomy (PRA) spectrometers on the Voyager 1 and 2 spacecraft was performed. This PRA data provided unique insights into the radio emission characteristics of the outer planets because of PRA's unique spectral response below the terrestrial ionospheric plasma frequency and its unprecedented proximity to the source. Of those results which were documented or published, this final report surveys only the highlights and cites references for more complete discussions. Unpublished results for Uranus, Neptune, and theoretical Ionian current distributions are presented at greater length. The most important conclusion to be drawn from these observations is that banded spectral emission is common to the radio emission below 1-2 MHz observed from all four Jovian planets. In every case multiple spectral features evolve on time scales of seconds to minutes. To the extent these features drift in frequency, they appear never to cross one another. The Neptunian spectral features appear to drift little or not at all, their evolution consisting principally of waxing and waning. Since other evidence strongly suggests that most or all of this radio emission is occurring near the local magnetospheric electron cyclotron frequency, this implies that this emission preferentially occurs at certain continually changing planetary radii. It remains unknown why certain radii might be favored, unless radial electric field components or other means serve to differentiate radially the magnetospheric plasma density, particle energy vectors, or particle coherence. Calculation of the spatial distribution and intensity of the Io-generated magnetospheric currents are also presented; these currents may be limited principally by wave impedance and local field strengths.

  12. Voyager 2 in the Vicinity of the Termination Shock with Voyager 1 Well Beyond

    NASA Astrophysics Data System (ADS)

    Stone, E. C.

    2007-12-01

    Voyager 2 began observing intense inward streaming of MeV ions from the termination shock in 2005 and has recently observed plasma oscillations excited by electron beams from the shock. Such beams occur on field lines that are tangential to planetary bow shocks, and Gurnett and Kurth proposed a similar topology for oscillations observed by Voyager 1 upstream of the termination shock. This suggests that Voyager 2 is now directly connected along the magnetic field to the shock, consistent with increasing intensities of sub-MeV ions. MHD models by Opher et al. and Pogorelov et al. indicate that direct connection along the spiral magnetic field to the non-spherical shock occurs when Voyager 2 is within ~3 AU from the shock. This suggests that if the shock moves steadily inward at >30 km/s, Voyager 2 may enter the heliosheath this year at a radial distance of <85 AU. The Voyager 2 data at the shock combined with Voyager 1 data at 105 AU in the heliosheath should help address questions such as the plasma flow immediately upstream of the shock and in the heliosheath, the source of anomalous cosmic rays and their relationship to the lower energy ions from the shock, the gradients of cosmic rays in the heliosheath, the effects of transients at the shock and beyond, and the north-south asymmetries in the shock and heliosheath

  13. 46 CFR 185.280 - Official Logbook for foreign voyages.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... wages due to a seaman who dies during the voyage and the gross amount of all deductions to be made from the wages; (ii) The sale of the property of a seaman who dies during the voyage, including a...

  14. 46 CFR 185.280 - Official Logbook for foreign voyages.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... wages due to a seaman who dies during the voyage and the gross amount of all deductions to be made from the wages; (ii) The sale of the property of a seaman who dies during the voyage, including a...

  15. Voyager high gain antenna calibration and pointing

    NASA Technical Reports Server (NTRS)

    Jahanshahi, M. H.

    1979-01-01

    A mathematical description of the data reduction technique used in analyzing Voyager calibration data is presented. To achieve the required telecommunication link performance, highly accurate pointing of the Voyager high gain antenna boresight relative to earth is necessary. To provide the optimum pointing, in-flight calibrations of the high gain antenna pointing mechanism are regularly made, and the design of the calibration and the antenna error models is delineated. It is shown that due to the use of wide angle sun sensors for celestial attitude control, the Voyager antenna error model differs from those of previous missions. Results of the in-flight calibrations and their implementation in improving the antenna pointing are also presented.

  16. Optical navigation during the Voyager Neptune encounter

    NASA Technical Reports Server (NTRS)

    Riedel, J. E.; Owen, W. M., Jr.; Stuve, J. A.; Synnott, S. P.; Vaughan, R. M.

    1990-01-01

    Optical navigation techniques were required to successfully complete the planetary exploration phase of the NASA deep-space Voyager mission. The last of Voyager's planetary encounters, with Neptune, posed unique problems from an optical navigation standpoint. In this paper we briefly review general aspects of the optical navigation process as practiced during the Voyager mission, and discuss in detail particular features of the Neptune encounter which affected optical navigation. New approaches to the centerfinding problem were developed for both stars and extended bodies, and these are described. Results of the optical navigation data analysis are presented, as well as a description of the optical orbit determination system and results of its use during encounter. Partially as a result of the optical navigation processing, results of scientific significance were obtained. These results include the discovery and orbit determination of several new satellites of Neptune and the determination of the size of Triton, Neptune's largest moon.

  17. 46 CFR 46.05-20 - Great Lakes voyage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Great Lakes voyage. 46.05-20 Section 46.05-20 Shipping... VESSELS Definitions Used in This Part § 46.05-20 Great Lakes voyage. A Great Lakes voyage is any voyage from a United States port or place on the Great Lakes to another United States port or place on...

  18. What's new, Voyager: The discoveries continue

    NASA Technical Reports Server (NTRS)

    Miner, Ellis D.

    1995-01-01

    The twin Voyager spacecraft, launched nearly two decades ago, continue to operate and are now searching for the edge of our solar system, the heliopause. Voyager's giant-planet flybys of Jupiter, Saturn, Uranus, and Neptune have provided data that are likely to remain the definitive data set for the foreseeable future and have led to many ongoing discoveries. As the spacecraft move toward the heliopause, they are also providing data on the structure of the heliosphere. This article discusses the discoveries resulting from the flyby and heliosphere data that have been made within the past five years.

  19. Voyager Reading Programs. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2010

    2010-01-01

    "Voyager Passport"[TM] is a supplemental reading intervention system for students in grades K-5. "Voyager Passport Reading Journeys"[TM] is a reading intervention program designed for adolescents who struggle with reading. The "Voyager Universal Literacy System"[R] is a K-3 reading program that includes a core reading curriculum; a progress…

  20. 46 CFR 4.05-15 - Voyage records, retention of.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Voyage records, retention of. 4.05-15 Section 4.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC MARINE CASUALTIES AND INVESTIGATIONS Notice of Marine Casualty and Voyage Records § 4.05-15 Voyage records, retention of. (a) The owner, agent, master, or...

  1. 46 CFR 175.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Vessels on an international voyage. 175.120 Section 175... 100 GROSS TONS) GENERAL PROVISIONS § 175.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with...

  2. 46 CFR 175.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Vessels on an international voyage. 175.120 Section 175... 100 GROSS TONS) GENERAL PROVISIONS § 175.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with...

  3. 46 CFR 175.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Vessels on an international voyage. 175.120 Section 175... 100 GROSS TONS) GENERAL PROVISIONS § 175.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with...

  4. 46 CFR 188.10-35 - International voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false International voyage. 188.10-35 Section 188.10-35... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-35 International voyage. (a) This section describes those voyages which are considered to be “international voyages” for the purposes of...

  5. 46 CFR 175.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Vessels on an international voyage. 175.120 Section 175... 100 GROSS TONS) GENERAL PROVISIONS § 175.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with...

  6. 46 CFR 188.10-35 - International voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false International voyage. 188.10-35 Section 188.10-35... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-35 International voyage. (a) This section describes those voyages which are considered to be “international voyages” for the purposes of...

  7. 46 CFR 188.10-35 - International voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false International voyage. 188.10-35 Section 188.10-35... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-35 International voyage. (a) This section describes those voyages which are considered to be “international voyages” for the purposes of...

  8. 46 CFR 114.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Vessels on an international voyage. 114.120 Section 114... PROVISIONS § 114.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with the applicable requirements of SOLAS...

  9. 46 CFR 114.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Vessels on an international voyage. 114.120 Section 114... PROVISIONS § 114.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with the applicable requirements of SOLAS...

  10. 46 CFR 188.10-35 - International voyage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false International voyage. 188.10-35 Section 188.10-35... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-35 International voyage. (a) This section describes those voyages which are considered to be “international voyages” for the purposes of...

  11. 46 CFR 175.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Vessels on an international voyage. 175.120 Section 175... 100 GROSS TONS) GENERAL PROVISIONS § 175.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with...

  12. 46 CFR 114.120 - Vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Vessels on an international voyage. 114.120 Section 114... PROVISIONS § 114.120 Vessels on an international voyage. A mechanically propelled vessel that carries more than 12 passengers on an international voyage must comply with the applicable requirements of SOLAS...

  13. 15 CFR 970.2502 - Post voyage report.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 3 2014-01-01 2014-01-01 false Post voyage report. 970.2502 Section 970.2502 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued....2502 Post voyage report. Within 30 days of the conclusion of each exploration voyage, the United...

  14. Enhancing Resilience in Youth through a 10-Day Developmental Voyage

    ERIC Educational Resources Information Center

    Hayhurst, Jill; Hunter, John A.; Kafka, Sarah; Boyes, Mike

    2015-01-01

    The present study sought to examine the potential for resilience to be enhanced in a group of youth participating in a developmental voyage, and to identify the factors that contribute to increased resilience following the voyage. Two studies are reported. Study 1 revealed that voyage participants experienced increased resilience over the course…

  15. Radio science with voyager at jupiter: initial voyager 2 results and a voyager 1 measure of the io torus.

    PubMed

    Eshleman, V R; Tyler, G L; Wood, G E; Lindal, G F; Anderson, J D; Levy, G S; Croft, T A

    1979-11-23

    Voyager 2 radio signals were observed essentially continuously during a grazing occultation of the spacecraft by the southern limb of Jupiter. Intensity data show a classic atmospheric occultation profile and the effects of turbulence and ionospheric focusing and defocusing. No reliable profile of the neutral atmosphere has yet been obtained, primarily because of a combination of large trajectory uncertainties and error multiplication effects associated with the grazing geometry of the Voyager 2 occultation. Analysis of the dispersive ionospheric refraction data yields preliminary profiles for the topside ionosphere at 66.7 degrees S (entry in the evening) and 50.1 degrees S (exit in the morning) that are reversed with respect to corresponding Voyager 1 profiles in terms of plasma concentration at a fixed altitude. Plasma scale heights and temperatures of 880 kilometers, 1200 K and 1040 kilometers, 1600 K were obtained for morning and evening conditions, respectively. Preliminary reduction of the pre-encounter occultation of Voyager 1 by the Io torus yields an average plasma density of about 1000 electrons per cubic centimeter.

  16. The Second Voyage of the Mimi.

    ERIC Educational Resources Information Center

    Bank Street Coll. of Education, New York, NY.

    This book includes 12 units that have been adapted from the television series "Voyage of the Mimi." Each unit includes the episode, an activity, and an expedition. The episodes introduce and accompany each episode of the television series. The activity is an extension of that episode which can be done in the classroom. Mapping skills, foreign…

  17. 46 CFR 122.503 - Voyage plan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS OPERATIONS Preparations...

  18. 46 CFR 122.503 - Voyage plan.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS OPERATIONS Preparations...

  19. 46 CFR 122.503 - Voyage plan.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Voyage plan. 122.503 Section 122.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS OPERATIONS Preparations...

  20. Voyager 2's encounter with Neptune

    NASA Technical Reports Server (NTRS)

    Mclaughlin, William I.

    1990-01-01

    The results of Voyager 2 observations of Neptune are reviewed. Observations of Neptune's Great Dark Spot, rotation atmosphere, magnetic field, rings, and satellites are discussed. Also, observations of Triton are considered, noting the presence of geyser activity on the satellite. Several photographs of features on both Neptune and Triton are presented.

  1. The Voyager flights to Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    1982-01-01

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

  2. The Hemispheric Roots of the Columbian Voyages.

    ERIC Educational Resources Information Center

    Shaffer, Lynda N.

    1991-01-01

    Urges that the search for origins of European exploration extend to Africa and East Asia and their international trade. Cites contributions of India and the Arabs, Chinese, and Malaysians. Emphasizes the importance of mathematics, navigation, and sailing technology. Argues that without these contributions the European voyages would not have been…

  3. Voyager electronic parts radiation program, volume 1

    NASA Technical Reports Server (NTRS)

    Stanley, A. G.; Martin, K. E.; Price, W. E.

    1977-01-01

    The Voyager spacecraft is subject to radiation from external natural space, from radioisotope thermoelectric generators and heater units, and from the internal environment where penetrating electrons generate surface ionization effects in semiconductor devices. Methods for radiation hardening and tests for radiation sensitivity are described. Results of characterization testing and sample screening of over 200 semiconductor devices in a radiation environment are summarized.

  4. Planetary radio astronomy observations from Voyager 2 near Jupiter

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Pearce, J. B.; Riddle, A. C.; Alexander, J. K.; Desch, M. D.; Kaiser, M. L.; Thieman, J. R.; Carr, T. D.; Gulkis, S.; Boischot, A.

    1979-01-01

    The Voyager 2 Planetary Radio Astronomy experiment to Jupiter has confirmed and extended to higher zenomagnetic latitudes results from the identical experiment carried by Voyager 1. The kilometric emissions discovered by Voyager 1 often extended to 1 megahertz or higher on Voyager 2 and often consisted of negatively, or less frequently, positively drifting narrowband bursts. On the basis of tentative identification of plasma wave emissions similar to those detected by Voyager 1, the plasma torus associated with Io appeared somewhat denser to Voyager 2 than it did to Voyager 1. The paper reports on quasi-periodic sinusoidal or impulsive bursts in the broadcast band range of wavelengths (800 to 1800 kHz). A Faraday effect appears at decametric frequencies, which probably results from propagation of the radiation near its sources on Jupiter. Finally, the occurrence of decametric emission in homologous arc families is discussed.

  5. Planetary radio astronomy observations from voyager 2 near jupiter.

    PubMed

    Pearce, J B; Riddle, A C; Warwick, J W; Alexander, J K; Desch, M D; Kaiser, M L; Thieman, J R; Carr, T D; Gulkis, S; Boischot, A; Leblanc, Y; Pedersen, B M; Staelin, D H

    1979-11-23

    The Voyager 2 Planetary Radio Astronomy experiment to Jupiter has confirmed and extended to higher zenomagnetic latitudes results from the identical experiment carried by Voyager 1. The kilometric emissions discovered by Voyager 1 often extended to 1 megahertz or higher on Voyager 2 and often consisted of negatively or, less frequently, positively drifting narrowband bursts. On the basis of tentative identification of plasma wave emissions similar to those detected by Voyager 1, the plasma torus associated with Io appeared somewhat denser to Voyager 2 than it did to Voyager 1. We report here on quasiperiodic sinusoidal or impulsive bursts in the broadcast band range of wavelengths (800 to 1800 kilohertz). A Faraday effect appears at decametric frequencies, which probably results from propagation of the radiation near its sources on Jupiter. Finally, we discuss the occurrence of decametric emission in homologous arc families.

  6. On whether or not voyager 1 has crossed the heliopause

    SciTech Connect

    Fisk, L. A.; Gloeckler, G.

    2014-07-01

    The Voyager 1 spacecraft is currently in the vicinity of the heliopause, which separates the heliosphere from the local interstellar medium. There has been a precipitous decrease in particles accelerated in the heliosphere, and a substantial increase in galactic cosmic rays (GCRs), suggesting easy escape of the former across the heliopause, and entry of the latter. The question is, has Voyager 1 actually crossed the heliopause and is it now in the interstellar medium? We contend that the evidence is inconclusive. The direction of the magnetic field observed by Voyager 1 is unchanged from the direction of the heliospheric magnetic field, and different from the expected direction of the interstellar magnetic field. However, the plasma density, which is measured from observations of plasma waves, is similar to the expected interstellar density and much larger than the solar wind plasma density observed by Voyager 2 (which has a working plasma detector) at smaller heliocentric distances than Voyager 1. In this paper, an analytic model is presented that is based upon and is consistent with all Voyager observations, and in which the higher plasma densities measured by Voyager 1 are due simply to compressed solar wind. Thus both the magnetic field and the plasma density observations are consistent with Voyager 1 still remaining well within the heliosheath. The model has a simple test: Voyager 1 should encounter a magnetic sector boundary crossing, where the behavior of particles accelerated in the heliosphere and the GCRs will be different from what Voyager 1 is now observing.

  7. Voyager 2 plasma wave observations at saturn.

    PubMed

    Scarf, F L; Gurnett, D A; Kurth, W S; Poynter, R L

    1982-01-29

    The first inbound Voyager 2 crossing of Saturn's bow shock [at 31.7 Saturn radii (RS), near local noon] and the last outbound crossing (at 87.4 RS, near local dawn) had similar plasma wave signatures. However, many other aspects of the plasma wave measurements differed considerably during the inbound and outbound passes, suggesting the presence of effects associated with significant north-south or noon-dawn asymmetries, or temporal variations. Within Saturn's magnetosphere, the plasma wave instrument detected electron plasma oscillations, upper hybrid resonance emissions, half-gyrofrequency harmonics, hiss and chorus, narrowband electromagnetic emissions and broadband Saturn radio noise, and noise bursts with characteristics of static. At the ring plane crossing, the plasma wave instrument also detected a large number of intense impulses that we interpret in terms of ring particle impacts on Voyager 2.

  8. Voyager 2 plasma wave observations at Saturn

    NASA Astrophysics Data System (ADS)

    Scarf, F. L.; Gurnett, D. A.; Kurth, W. S.; Poynter, R. L.

    1982-01-01

    The first inbound Voyager 2 crossing of Saturn's bow shock (at 31.7 Saturn radii near local noon) and the last outbound crossing (at 87.4 Saturn radii near local dawn) had similar plasma wave signatures. However, many other aspects of the plasma wave measurements differed considerably during the inbound and outbound passes, suggesting the presence of effects associated with significant north-south or noon-dawn asymmetries, or temporal variations. Within Saturn's magnetosphere, the plasma wave instrument detected electron plasma oscillations, upper hybrid resonance emissions, half-gyrofrequency harmonics, hiss and chorus, narrowband electromagnetic emissions and broadband Saturn radio noise, and noise bursts with characteristics of static. At the ring plane crossing, the plasma wave instrument also detected a large number of intense impulses that were interpreted in terms of ring particle impacts on Voyager 2.

  9. The Neptune System in Voyager's Afterglow.

    PubMed

    Kerr, R A

    1989-09-29

    Any time the view of a planet leaps from a fuzzy dot accompanied by two pinpoints of light to the riveting details of swirling clouds, rings, cratered moonlets, and even individual dust particles, planetary science is going to be in for some upheaval. Voyager 2's encounter with Neptune was no exception. Something as seemingly innocuous as an hour or two shift in the new length of a Neptunian day is giving meteorologists and physicists fits. And Neptune's canted, complex magnetic field found by Voyager knocks into a cocked hat most ideas about why a similar field at Uranus was unique. But there were more reassuring discoveries as well. Here are samplings of both sorts of findings.

  10. Voyager 2 radio observations of uranus.

    PubMed

    Warwick, J W; Evans, D R; Romig, J H; Sawyer, C B; Desch, M D; Kaiser, M L; Alexander, J K; Carr, T D; Staelin, D H; Gulkis, S; Poynter, R L; Aubier, M; Boischot, A; Leblanc, Y; Lecacheux, A; Pedersen, B M; Zarka, P

    1986-07-01

    Within distances to Uranus of about 6 x 10(6) kilometers (inbound) and 35 x 10(6) kilometers (outbound), the planetary radio astronomy experiment aboard Voyager 2 detected a wide variety of radio emissions. The emission was modulated in a period of 17.24 +/- 0.01 hours, which is identified as the rotation period of Uranus' magnetic field. Of the two poles where the axis of the off-center magnetic dipole (measured by the magnetometer experiment aboard Voyager 2) meets the planetary surface, the one closer to dipole center is now located on the nightside of the planet. The radio emission generally had maximum power and bandwidth when this pole was tipped toward the spacecraft. When the spacecraft entered the nightside hemisphere, which contains the stronger surface magnetic pole, the bandwidth increased dramatically and thereafter remained large. Dynamically evolving radio events of various kinds embedded in these emissions suggest a Uranian magnetosphere rich in magnetohydrodynamic phenomena.

  11. Planning the Voyager spacecraft's mission to Uranus

    NASA Technical Reports Server (NTRS)

    Plagemann, Stephen H.

    1987-01-01

    The application of the systems engineering process to the planning of the Voyager spacecraft mission is described. The Mission Planning Office prepared guidelines that controlled the use of the project and multimission resources and spacecraft consumables in order to obtain valuable scientific data at an acceptable risk level. Examples of mission planning which are concerned with the design of the Deep Space Network antenna, the uplink window for transmitting computer command subsystem loads, and the contingency and risk assessment functions are presented.

  12. Ganymede - Comparison of Voyager and Galileo Resolution

    NASA Technical Reports Server (NTRS)

    1996-01-01

    These images demonstrate the dramatic improvement in the resolution of pictures that NASA's Galileo spacecraft is returning compared to previous images of the Jupiter system. The frame at left was taken by the Voyager 2 spacecraft when it flew by in 1979, with a resolution of about 1.3 kilometers (0.8 mile) per pixel. The frame at right showing the same area was captured by Galileo during its first flyby of Ganymede on June 27, 1996; it has a resolution of about 74 meters (243 feet) per pixel, more than 17 times better than that of the Voyager image. In the Voyager frame, line-like bright and dark bands can be seen but their detailed structure and origin are not clear. In the Galileo image, each band is now seen to be composed of many smaller ridges. The structure and shape of the ridges permit scientists to determine their origin and their relation to other terrains, helping to unravel the complex history of the planet-sized moon. In each of these frames, north is to the top, and the sun illuminates the surface from the lower left nearly overhead (about 77 degrees above the horizon). The area shown, at latitude 10 degrees north, 167 degrees west, is about 35 by 55 kilometers (25 by 34 miles). The image was taken June 27 when Galileo was 7,448 kilometers (4.628 miles) away from Ganymede. The Jet Propulsion Laboratory manages the Galileo mission for NASA's Office of Space Science.

  13. Voyager 2 Movie of Saturn's Moon: Phoebe

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Voyager 2 took this photo sequence of Saturn's outer satellite, Phoebe, on Sept. 4, 1981, from 2.2 million kilometers (1.36 million miles) away. The top image is the normal version and the bottom is an enhanced version to increase resolution. This sequence lasts 23.4 hours and contains 35 images. The early images were taken about 43 minutes apart, while the later ones are about 29 minutes apart. There are two significant gaps in the sequence: images 7 and 8 are separated by 2.3 hours and images 19 and 20 are separated by 2.8 hours.

    Because the sunlight is coming from the left, mountains and ridges can best be seen as they reflect the sunlight near the terminator (right side of Phoebe). Other intrinsically bright spots can be seen rotating across the whole disk. In this time-lapse sequence, Phoebe appears to be a lumpy spheroid with possible large mountains sometimes showing on the limb (left side of Phoebe). The photos show that Phoebe is about 220 kilometers (132 miles) in diameter. Its rotation period (length of day) was determined from this set of images to be 9.4 hours (see Thomas, P., et al, 'Phoebe: Voyager 2 Observations', Journal of Geophysical Research, vol. 88, p. 8736, 1 November 1983).

    These images were processed by the Multimission Image Processing Laboratory of the Jet Propulsion Laboratory. The Voyager Project is managed for NASA by the Jet Propulsion Laboratory.

  14. Voyager telecommunications - The broadcast from Jupiter

    NASA Technical Reports Server (NTRS)

    Edelson, R. E.; Madsen, B. D.; Davis, E. K.; Garrison, G. W.

    1979-01-01

    The means by which the data collected by the Voyager 1 mission to Jupiter were returned to earth are presented. Radio links between the earth and the spacecraft are used for the transmission of both imaging and nonimaging telemetry from the spacecraft and commands from the earth and for radiometric observations of the spacecraft and its environment. Features which have lead to vast improvements in the capability of the Voyager telecommunications system over that of previous space probes include the use of X-band rather than S-band telemetry, a dual power X-band traveling wave tube amplifier, a 3.7 m spacecraft antenna and a single channel telemetry system with concatenated coding. Communications equipment at the three ground complexes of the Deep Space Network for telemetry reception includes 64 m steerable antennas, cryogenic maser preamplifiers and a phase-lock loop receiver. Voyager 1 has met or exceeded all of its telecommunications requirements, providing a 98% data return and a total of 2 x 10 to the 11th data bits during the Jupiter encounter.

  15. Voyager 2's encounter with the gas giants

    NASA Astrophysics Data System (ADS)

    Miner, E. D.

    1990-07-01

    The findings made by Voyager 2 as it passed by the gas giants are reviewed. The unexpected problems that had to be overcome during the mission, including receiver failure and scan platform problems, are described. The scientific instrumentation aboard Voyager is briefly examined, and the major types of Voyager scientific investigations and principal investigators are listed. The scientific findings regarding the atmospheres, thermal properties, electromagnetic environments, ring systems, satellite surfaces, body properties, and bulk properties are examined.

  16. View of Callisto from Voyager and Galileo

    NASA Technical Reports Server (NTRS)

    1996-01-01

    View of Callisto, most distant of the four large moons of Jupiter. This mosaic was prepared from images obtained by three spacecraft: Voyager 1 (left side), Galileo (middle), and Voyager 2 data (right side). The Voyager data were taken in 1979 but left a 'gap' centered at longitude 290 degrees in the trailing hemisphere of Callisto. The Galileo Solid-State Imaging system photographed this area on its second orbit around Jupiter on 9 September, 1996 Universal Time. The resolution of the Galileo data is 4.3 kilometers/pixel (2.7 miles), meaning that the smallest visible feature is about 12 kilometers (7 miles) across. North is to the top of the picture.

    Features of interest in the new Galileo data include a dark, smooth area in the northern latitudes (upper third) which appears to mantle older terrain. This could be dark ejecta from a small impact crater. Also visible is a fresh, sharp-rimmed crater some 90 km (56 miles) across named Igaluk (center left third of picture), and a bright zone in the south polar area (bottom of image) which could be an impact scar.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  17. Voyager telecommunications: the broadcast from jupiter.

    PubMed

    Edelson, R E; Madsen, B D; Davis, E K; Garrison, G W

    1979-06-01

    Sweeping past Jupiter, the Voyager 1 spacecraft presages a new era in the exploration of the solar system. Not since the TV return from Apollo has a spacecraft returned information of such volume and pictures of such startling clarity. Yet this feat was accomplished from a distance 1770 times as great as that of the lunar adventure. The communication system responsible for this remarkable achievement is a oompilation of elements ranging from tiny integrated circuits to enormous ground antennas. This article seeks to describe the way in which data are returned from these fascinating, faraway bodies and to convey the excitement of the engineering work that supports our scientific endeavors.

  18. Sequencing Voyager II for the Uranus encounter

    NASA Technical Reports Server (NTRS)

    Morris, R. B.

    1986-01-01

    The process of developing the programmed sequence of events necessary for the Voyager 2 spacecraft to return desired data from its Uranus encounter is discussed. The major steps in the sequence process are reviewed, and the elements of the Mission Sequence Software are described. The design phase and the implementation phase of the sequence process are discussed, and the Computer Command Subsystem architecture is examined in detail. The software's role in constructing the sequences and converting them into onboard programs is elucidated, and the problems unique to the Uranus encounter sequences are considered.

  19. Voyager imaging of Triton's clouds and hazes

    NASA Technical Reports Server (NTRS)

    Rages, Kathy; Pollack, James B.

    1992-01-01

    Results are presented from a detailed analysis of Voyager images of Triton obtained at the highest solar phase angles; these have been fit to Mie scattering models in order to obtain the mean particle sizes, number densities, and the vertical extent of the two different scattering components of the Triton atmosphere. The 0.001-0.01 optical depths of about 0.17 micron particles are vertically distributed with scale heights of about 10 km throughout Triton. A number of properties of the haze particles in question suggest that they are composed of photochemically produced gases which have condensed in the cold lower atmosphere of Triton.

  20. This view of Jupiter was taken by Voyager 1

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This view of Jupiter was taken by Voyager 1. This image was taken through color filters and recombined to produce the color image. This photo was assembled from three black and white negatives by the Image Processing Lab at Jet Propulsion Laboratory. JPL manages and controls the VOyager project for NASA's Office of Space Science.

  1. 15 CFR 970.2502 - Post voyage report.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE GENERAL REGULATIONS OF THE ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Pre-license Exploration § 970.2502 Post voyage report. Within 30 days of the conclusion of each exploration voyage, the United...

  2. Getting Your Sea Legs

    PubMed Central

    Stoffregen, Thomas A.; Chen, Fu-Chen; Varlet, Manuel; Alcantara, Cristina; Bardy, Benoît G.

    2013-01-01

    Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning. PMID:23840560

  3. Going from lectures to expeditions: Creating a virtual voyage in undergraduate ocean science education

    NASA Astrophysics Data System (ADS)

    Reed, D.; Garfield, N.; Locke, J.; Anglin, J.; Karl, H.; Edwards, B.

    2003-04-01

    The WWW provides for new collaborations in distributed learning in higher education. The lead author has developed a highly successful online course at the undergraduate level with an enrollment of more than 300 non-science majors each year, We are currently initiating a new focus for the course by emphasizing sea-going research, primarily in the northeastern Pacific Ocean, through the development of a virtual oceanographic voyage over the WWW. The "virtual voyage" courseware combines elements of experiential learning with anytime, anywhere access of the WWW to stimulate inquiry-based learning in the ocean sciences. The first leg of the voyage is currently being synthesized from contemporary ocean research sponsored by a collaboration of U.S. government agencies, including NSF, NOAA, and the USGS. The initial portion of this effort involves transforming portions of USGS Circular 1198, Beyond the Golden Gate -- Oceanography, Geology, Biology, and Environmental Issues in the Gulf of the Farallones, into an interactive expedition by which students participate as scientists aboard a research vessel departing from San Francisco. Virtual experiments on the voyage are patterned after research cruises over the past decade in two national marine sanctuaries and include the technologies of data acquisition and data analysis, as well as providing insight into the methodologies of working marine scientists. Real-time data for monitoring the marine environment are embedded into several modules; for example, students will analyze data from offshore buoys and satellite imagery to assess ocean conditions prior to departing from port. Multibeam sonar is used to create seafloor maps near the Golden Gate Bridge and sediment cores provide evidence of sea-level change in the region. Environmental studies in the region include locating canisters of low-level radioactive waste and assessing potential sites for the disposal for dredged materials from the San Francisco Bay. Upon completion

  4. Idealized Voyager Jovian magnetosphere shape and field

    SciTech Connect

    Engle, I.M. )

    1991-05-01

    A magnetic field arising from the Jovian equatorial sheet current deduced from Voyager 1 and 2 observations has been added to a planetary dipole field to provide a model of magnetic field inside the magnetopause. This internal field was used to calculate the magnetopause surface in a cyclic process. During each cycle, the surface was calculated, and the resulting field due to currents on the magnetopause was calculated for inclusion in the total field used to calculate the next-order surface. The resulting magnetopause is, as anticipated, flatter in shape than one resulting primarily from a dipole internal field source, but not dissimilar in overall height-to-width configuration to that of the magnetopause calculated for the larger inflated magnetopause observed by Pioneer 10. An array of magnetic field values for locations internal and external to the magnetopause due to currents on the surface has been computed by integrating over the entire magnetopause. A model for the total magnetospheric field of this semi-inflated magnetosphere has been constructed by adding this latter contribution to the internal source fields to obtain a global model of a semi-inflated Jovianlike magnetospheric field. The magnitude of the contribution of the surface currents to the total magnetic field in the region of the orbits of the Galilean satellites is calculated to be considerably larger for this Voyager model than for the Pioneer model.

  5. Voyager disk-integrated photometry of triton.

    PubMed

    Hillier, J; Helfenstein, P; Verbiscer, A; Veverka, J; Brown, R H; Goguen, J; Johnson, T V

    1990-10-19

    Hapke's photometric model has been combined with a plane-parallel thin atmospheric haze model to describe Voyager whole-disk observations of Triton, in the violet (0.41 microm), blue (0.48 microm), and green (0.56 microm) wavelength bands, in order to obtain estimates of Triton's geometric albedo, phase integral, and Bond albedo. Phase angle coverage in these filters ranging from approximately 12 degrees to 159 degrees was obtained by combining narrow- and wide-angle camera images. An upturn in the data at the highest phase angles observed can be explained by including scattering in a thin atmospheric haze layer with optical depths systematically decreasing with wavelength from approximately 0.06 in the violet to 0.03 for the green filter data. The geometric albedo, phase integral, and spherical albedo of Triton in each filter corresponding to our best fit Hapke parameters yield an estimated Bond albedo of 0.82 +/- 0.05. If the 14-microbar N(2) atmosphere detected by Voyager is in vapor equilibrium with the surface (therefore implying a surface temperature of 37.5 K), our Bond albedo implies a surface emissivity of 0.59 +/- 0.16.

  6. Voyager absolute far-ultraviolet spectrophotometry of hot stars

    NASA Technical Reports Server (NTRS)

    Holberg, J. B.; Forrester, W. T.; Shemansky, D. E.; Barry, D. C.

    1982-01-01

    Voyager observations in the 912-1200 A spectral region are used to indirectly intercompare absolute stellar spectrophotometry from previous experiments. Measurements of hot stars obtained by the Voyager 1 and 2 ultraviolet spectrometers show considerably higher 912-1200 A continuum fluxes than the recent observations of Brune et al. (1979) and Carruthers et al. (1981). The intercomparisons show all observations in basic agreement near 1200 A. The Carruthers et al. flux measurements are preferred down to 1050 A at which point the Voyager and Brune et al. values are respectively 60% higher and 60% lower. Below 1050 A the diasgreement among the observations becomes very large and the fluxes predicted by model atmospheres have been adopted. The pure hydrogen line-blanketed model atmosphere calculations of Wesemael et al. 1980) in comparison with Voyager observations of HZ 43 are used to adjust the Voyager calibration below 1050 A. This adjusted Voyager calibration, which is in good agreement with current model atmosphere fluxes for both early-type stars and DA white dwarfs, will be used for Voyager astronomical observations.

  7. Voyager 1 Jupiter Southern Hemisphere Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This movie shows a portion of Jupiter in the southern hemisphere over 17Jupiter days. Above the white belt, notice the series of atmospheric vortices headed west. Even these early approach frames show wild dynamics in the roiling environment south of the white belt. Notice the small tumbling white cloud near the center.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 17 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Blue filter around Feb. 1, 1979. The spacecraft was about 37 million kilometers from Jupiter at that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  8. Plasma conditions inside Io's orbit - Voyager measurements

    NASA Astrophysics Data System (ADS)

    Bagenal, F.

    1985-01-01

    The Voyager 1 ion data that were obtained inside the orbit of Io allow accurate determination of convective velocity, temperature, and density of the major ionic species (S+, O+, S2+ and O2+ ions). The irregular radial profiles of ion temperature and flux tube content are not consistent with simple models of radial transport of plasma from a source near Io. The evidence of a source of ions well inside Io's orbit is provided by the detection of molecular (SO2+) ions at 5.3 RJ, the prevalence of non-Maxwellian tails to the ion distribution functions, the persistent presence of oxygen ions throughout the inner torus, and a 1 - 3% lag behind corotation outside 5.4 RJ.

  9. Color Voyager 2 Image Showing Crescent Uranus

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This image shows a crescent Uranus, a view that Earthlings never witnessed until Voyager 2 flew near and then beyond Uranus on January 24, 1986. This planet's natural blue-green color is due to the absorption of redder wavelengths in the atmosphere by traces of methane gas. Uranus' diameter is 32,500 miles, a little over four times that of Earth. The hazy blue-green atmosphere probably extends to a depth of around 5,400 miles, where it rests above what is believed to be an icy or liquid mixture (an 'ocean') of water, ammonia, methane, and other volatiles, which in turn surrounds a rocky core perhaps a little smaller than Earth.

  10. Voyager disk-integrated photometry of Triton

    NASA Technical Reports Server (NTRS)

    Hillier, J.; Helfenstein, P.; Verbiscer, A.; Veverka, J.; Brown, R. H.; Goguen, J.; Johnson, T. V.

    1990-01-01

    Hapke's (1981) photometric model has been combined with a plane-parallel thin atmospheric haze model to describe Voyager whole-disk observations of Triton, in the violet, blue, and green wavelength bands, in order to obtain estimates of Triton's geometric albedo, phase integral, and Bond albedo. Phase angle coverage in these filters ranging from about 12 to 159 deg was obtained by combining narrow- and wide-angle camera images. An upturn in the data at the highest phase angles observed can be explained by including scattering in a thin atmospheric haze layer with optical depths systematically decreasing with wavelength from about 0.06 in the violet to 0.03 for the green filter data.

  11. Uruk Sulcus Mosaic - Galileo over Voyager Data

    NASA Technical Reports Server (NTRS)

    1996-01-01

    A mosaic of four Galileo images of the Uruk Sulcus region on Ganymede (Latitude 11 N, Longitude: 170 W) is shown overlayed on the data obtained by the Voyager 2 spacecraft in 1979. North is to the top of the picture, and the sun illuminates the surface from the lower left, nearly overhead. The area shown is about 120 by 110 kilometers (75 by 68 miles) in extent and the smallest features that can be discerned are 74 meters (243 feet) in size in the Galileo images and 1.3 kilometers (0.8 miles) in the Voyager data. The higher resolution Galileo images unveil the details of parallel ridges and troughs that are principal features in the brighter regions of Ganymede. High photometric activity (large light contrast at high spatial frequencies) of this ice-rich surface was such that the Galileo camera's hardware data compressor was pushed into truncating lines. The north-south running gap between the left and right halves of the mosaic is a result of line truncation from the normal 800 samples per line to about 540. The images were taken on 27 June, 1996 Universal Time at a range of 7,448 kilometers (4,628 miles) through the clear filter of the Galileo spacecraft's imaging system.

    Launched in October 1989, Galileo entered orbit around Jupiter on December 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  12. Jules Verne Voyager, Jr: An Interactive Map Tool for Teaching Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Hamburger, M. W.; Meertens, C. M.

    2010-12-01

    We present an interactive, web-based map utility that can make new geological and geophysical results accessible to a large number and variety of users. The tool provides a user-friendly interface that allows users to access a variety of maps, satellite images, and geophysical data at a range of spatial scales. The map tool, dubbed 'Jules Verne Voyager, Jr.', allows users to interactively create maps of a variety of study areas around the world. The utility was developed in collaboration with the UNAVCO Consortium for study of global-scale tectonic processes. Users can choose from a variety of base maps (including "Face of the Earth" and "Earth at Night" satellite imagery mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others), add a number of geographic and geophysical overlays (coastlines, political boundaries, rivers and lakes, earthquake and volcano locations, stress axes, etc.), and then superimpose both observed and model velocity vectors representing a compilation of 2933 GPS geodetic measurements from around the world. A remarkable characteristic of the geodetic compilation is that users can select from some 21 plates' frames of reference, allowing a visual representation of both 'absolute' plate motion (in a no-net rotation reference frame) and relative motion along all of the world's plate boundaries. The tool allows users to zoom among at least three map scales. The map tool can be viewed at http://jules.unavco.org/VoyagerJr/Earth. A more detailed version of the map utility, developed in conjunction with the EarthScope initiative, focuses on North America geodynamics, and provides more detailed geophysical and geographic information for the United States, Canada, and Mexico. The ‘EarthScope Voyager’ can be accessed at http://jules.unavco.org/VoyagerJr/EarthScope. Because the system uses pre-constructed gif images and overlays, the system can rapidly create and display maps to a large number of users

  13. Energetic Particles at Voyager 1 in the Interstellar Medium and Voyager 2 in the Heliosheath

    NASA Astrophysics Data System (ADS)

    Decker, Robert; Roelof, Edmond; Krimigis, Stamatios; Hill, Matthew

    Voyager 1 (at 128 AU, N35(°) lat. in mid-2014) evidently made a transition from the heliosheath into the local interstellar medium on or about doy 238 of 2012 at 121.6 AU. Prior to the doy 238 transition, Voyager 1 passed through two partial “depletion regions” during 2012 doys 210-215 and 226-234. In the depletion regions, intensities of charged particles of heliospheric origin (suprathermal ions, ACRs, low-energy electrons) decreased, while those of galactic origin (GCR ions and electrons) increased, and the magnetic field intensity increased but its direction remained close to that measured in the heliosheath. Low-energy helosheath electrons 26-70 keV begin decreasing ≈2012.5, dropped sharply at the 1st GCR increase, made a weak recovery between 1st and 2nd GCR increase, and dropped to background levels after 2nd GCR increase. After 2012/238 the intensity decreases of protons 3-30 MeV showed pancake-like pitch-angle distributions. At Voyager 2 (at 105 AU, S31(°) lat.), which is still in the heliosheath, low-energy ions from at least 0.03 to 30 MeV showed increasing 1st order anisotropies during the period 2013.0-2013.3 that are directed in the +T direction, i.e., away from the heliosheath nose toward its flank from the perspective of Voyager 2 (at a longitude ≈45(°) from the nose). Both the intensities and associated partial pressures of low-energy heliosheath ions had decreased at Voyager 2 since its termination shock crossing on 2007/242. Intensities of suprathermal ions ≈100 keV, which dropped by a factor ≈7 from the shock crossing to 2013.3, have since increased by a factor ≈2, apparently in response to a transient disturbance that is also associated with the enhanced tangential streaming of energetic ions in the +T direction.

  14. Hybridity, race, and science: the voyage of the Zaca, 1934-1935.

    PubMed

    Anderson, Warwick

    2012-06-01

    In 1929 and 1934-1935, the physical anthropologist Harry L. Shapiro voyaged in the South Seas on the Mahina-l-Te-Pua and the Zaca, measuring mixed-race islanders, including the descendants of the Bounty mutineers on Pitcairn Island. His research in Polynesian hybridity reflects the growing cultural and scientific investment of the United States in the Pacific during this period. Shapiro's oceanic adventures and intimate encounters prompted him to discount typological speculation and emphasize instead the liberal Boasian program in physical anthropology, giving him the confidence to refigure his evaluations of racial difference. The seaborne investigatory enterprise came to influence U.S. racial thought, adding impetus to the condemnation of racism in science. On his return from the South Seas, Shapiro tried to get his fellow physical anthropologists to issue a manifesto opposing the harnessing of their science to racial discrimination and prejudice.

  15. The voyager 2 encounter with the uranian system.

    PubMed

    Stone, E C; Miner, E D

    1986-07-01

    An overview of the Voyager 2 encounter with Uranus is presented, inclding a brief discussion of the trajectory and the planned observations as well as the highlights of the results described in the 11 companion papers.

  16. Saturn radio emission and the solar wind - Voyager-2 studies

    SciTech Connect

    Desch, M.D.; Rucker, H.O.

    1985-01-01

    Voyager 2 data from the Plasma Science experiment, the Magnetometer experiment and the Planetary Radio Astronomy experiment were used to analyze the relationship between parameters of the solar wind/interplanetary medium and the nonthermal Saturn radiation. Solar wind and interplanetary magnetic field properties were combined to form quantities known to be important in controlling terrestrial magnetospheric processes. The Voyager 2 data set used in this investigation consists of 237 days of Saturn preencounter measurements. However, due to the immersion of Saturn and the Voyager 2 spacecraft into the extended Jupiter magnetic tail, substantial periods of the time series were lacking solar wind data. To cope with this problem a superposed epoch method (CHREE analysis) was used. The results indicate the superiority of the quantities containing the solar wind density in stimulating the radio emission of Saturn - a result found earlier using Voyager 1 data - and the minor importance of quantities incorporating the interplanetary magnetic field. 10 references.

  17. Voyager's discoveries mount on final rush to Neptune

    SciTech Connect

    Smith, B.A.

    1989-08-01

    On its final approach to Neptune, Voyager 2 detected not only two new moons, designated 1989N5 and 1989N6, but shadows cast by high cyrrus-type clouds on a lower cloud deck in the planet's south polar region. Voyager scientists have also been carefully watching for massive features in Neptune's unexpectedly dynamic atmosphere; such similarities were noted between Jupiter's Great Red Spot and Neptune's Great Dark Spot, a feature comparable to the earth in size, as a 20-22 deg south latitude location. Voyager is programmed to fly about 25,000 miles above Triton on its way out of the plane of the ecliptic. Voyager will be imaging Triton during the end of a 100-year cycle in which its south pole has been subjected to increased solar heating.

  18. Voyager: Exploratory Analysis via Faceted Browsing of Visualization Recommendations.

    PubMed

    Wongsuphasawat, Kanit; Moritz, Dominik; Anand, Anushka; Mackinlay, Jock; Howe, Bill; Heer, Jeffrey

    2016-01-01

    General visualization tools typically require manual specification of views: analysts must select data variables and then choose which transformations and visual encodings to apply. These decisions often involve both domain and visualization design expertise, and may impose a tedious specification process that impedes exploration. In this paper, we seek to complement manual chart construction with interactive navigation of a gallery of automatically-generated visualizations. We contribute Voyager, a mixed-initiative system that supports faceted browsing of recommended charts chosen according to statistical and perceptual measures. We describe Voyager's architecture, motivating design principles, and methods for generating and interacting with visualization recommendations. In a study comparing Voyager to a manual visualization specification tool, we find that Voyager facilitates exploration of previously unseen data and leads to increased data variable coverage. We then distill design implications for visualization tools, in particular the need to balance rapid exploration and targeted question-answering.

  19. 33 CFR 151.2055 - Deviation from planned voyage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... United States § 151.2055 Deviation from planned voyage. As long as ballast water exchange (BWE) is an... (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL...

  20. 33 CFR 151.2055 - Deviation from planned voyage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... United States § 151.2055 Deviation from planned voyage. As long as ballast water exchange (BWE) is an... (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL...

  1. 33 CFR 151.2055 - Deviation from planned voyage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... United States § 151.2055 Deviation from planned voyage. As long as ballast water exchange (BWE) is an... (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL...

  2. 15 CFR 970.2502 - Post voyage report.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Pre-license Exploration § 970... citizen engaging in the voyage shall submit to NOAA a report containing any environmental data...

  3. IS VOYAGER 1 INSIDE AN INTERSTELLAR FLUX TRANSFER EVENT?

    SciTech Connect

    Schwadron, N. A.; McComas, D. J.

    2013-12-01

    Plasma wave observations from Voyager 1 have recently shown large increases in plasma density, to about 0.1 cm{sup –3}, consistent with the density of the local interstellar medium. However, corresponding magnetic field observations continue to show the spiral magnetic field direction observed throughout the inner heliosheath. These apparently contradictory observations may be reconciled if Voyager 1 is inside an interstellar flux transfer event—similar to flux transfer events routinely seen at the Earth's magnetopause. If this were the case, Voyager 1 remains inside the heliopause and based on the Voyager 1 observations we can determine the polarity of the interstellar magnetic field for the first time.

  4. VOYAGER OBSERVATIONS OF THE DIFFUSE FAR-ULTRAVIOLET RADIATION FIELD

    SciTech Connect

    Murthy, Jayant; Henry, Richard Conn; Holberg, Jay B.

    2012-03-01

    The two Voyager spacecraft have completed their planetary exploration mission and are now probing the outer realms of the heliosphere. The Voyager ultraviolet spectrometers continued to operate well after the Voyager 2 Neptune encounter in 1989. We present a complete database of diffuse radiation observations made by both Voyagers: a total of 1943 spectra (500-1600 A) scattered throughout the sky. These include observations of dust-scattered starlight, emission lines from the hot interstellar medium, and a number of locations where no diffuse radiation was detected, with the very low upper limit of about 25 photons cm{sup -2} s{sup -1} sr{sup -1} A{sup -1}. Many of these observations were from late in the mission when there was significantly less contribution from interplanetary emission lines and thus less contamination of the interstellar signal.

  5. 46 CFR 122.280 - Official logbook for foreign voyages.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... seaman, the following information required by 46 U.S.C. 10702: (i) The wages due to a seaman who dies... the property of a seaman who dies during the voyage, including a statement of each article sold...

  6. Erratum: Voyager Color Photometry of Saturn's Main Rings

    NASA Technical Reports Server (NTRS)

    Estrada, Paul R.; Cuzzi, Jeffrey N.; Showalter, Mark R.; DeVincenzi, Donald (Technical Monitor)

    2002-01-01

    We correct a calibration error in our earlier analysis of Voyager color observations of Saturn's main rings at 14 deg phase angle and present thoroughly revised and reanalyzed radial profiles of the brightness of the main rings in Voyager G, V, and UV filters, and ratios of these brightnesses. These results are consistent with more recent HST results at 6 deg phase angle, once allowance is made for plausible phase reddening of the rings. Unfortunately, the Voyager camera calibration factors are simply not sufficiently well known for a combination of the Voyager and HST data to be used to constrain the phase reddening quantitatively. However, some interesting radial variations in reddening between 6-14 deg phase angles are hinted at. We update a ring-and-satellite color vs. albedo plot from Cuzzi and Estrada in several ways. The A and B rings are still found to be in a significantly redder part of color-albedo space than Saturn's icy satellites.

  7. 15 CFR 970.2502 - Post voyage report.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Pre-license Exploration § 970... citizen engaging in the voyage shall submit to NOAA a report containing any environmental data...

  8. 15 CFR 970.2502 - Post voyage report.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Pre-license Exploration § 970... citizen engaging in the voyage shall submit to NOAA a report containing any environmental data...

  9. Nick Sagan Reflects on Voyager 1 and the Golden Record

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2013-10-01

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

  10. The Voyager Spacecraft. [Jupiter-Saturn mission investigations

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The configuration of the Voyager spacecraft is described as well as the subsystems for power, temperature control, attitude control, and propulsion. Major features of Jupiter and Saturn including their atmospheres, surfaces, and natural satellites are discussed. The 13 onboard experiments and their scientific objectives are explained. Other aspects covered include tracking, data acquisition, and the mission control and computing center. Members of the Voyager team and subcontractors are listed.

  11. Triton and Nereid astrographic observations from Voyager 2

    NASA Technical Reports Server (NTRS)

    Jacobson, R. A.

    1991-01-01

    This article describes the reduced astrographic observations of Triton and Nereid derived from Voyager 2 imaging data. The data set contains 496 sets of spacecraft-centered fight ascension and declination observations and includes all of the observations used in Voyager encounter operations. The details of the conversion process from imaging to astrographic observations are given. The effect of using the astrographic rather than imaging form in ephemeris improvement is evaluated.

  12. The helium abundance of Jupiter from Voyager

    NASA Technical Reports Server (NTRS)

    Gautier, D.; Conrath, B.; Flasar, F. M.; Hanel, R. A.; Kunde, V. G.; Chedin, A.; Scott, N.

    1980-01-01

    Full disk measurements recorded 31 days before the Voyager 1 encounter with Jupiter by the radiometer of the infrared instrument, IRIS, indicate a geometric albedo of 0.274 + or - 0.013. Combining this measurement with the Pioneer derived phase integral of 1.25 and our error estimate of 0.1 yields a Jovian Bond albedo of 0.343 + or - 0.032. Infrared spectra recorded at the same time by the Michelson interferometer, along with a model extrapolation to low wave numbers not covered by the instrument, yield a thermal emission of (1.359 + or - 0.014) .001 W cm to the (-2) power. As in the case of the albedo measurement, the quoted errors in the emission measurement reflect estimates of systematic effects and are uncertain while the random component is negligible. From these measurements the internal heat flux of Jupiter is estimated to be (5.444 + or - 0.425) .0001 W cm to the (-2) power, and the energy balance defined as the ratio of emitted thermal to absorbed solar energy is 1.668 + or - 0.085.

  13. Voyager spacecraft images of Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Birnbaum, M. M.

    1982-01-01

    The Voyager imaging system is described, noting that it is made up of a narrow-angle and a wide-angle TV camera, each in turn consisting of optics, a filter wheel and shutter assembly, a vidicon tube, and an electronics subsystem. The narrow-angle camera has a focal length of 1500 mm; its field of view is 0.42 deg and its focal ratio is f/8.5. For the wide-angle camera, the focal length is 200 mm, the field of view 3.2 deg, and the focal ratio of f/3.5. Images are exposed by each camera through one of eight filters in the filter wheel on the photoconductive surface of a magnetically focused and deflected vidicon having a diameter of 25 mm. The vidicon storage surface (target) is a selenium-sulfur film having an active area of 11.14 x 11.14 mm; it holds a frame consisting of 800 lines with 800 picture elements per line. Pictures of Jupiter, Saturn, and their moons are presented, with short descriptions given of the area being viewed.

  14. New Voyager radio spectrograms of Uranus

    NASA Technical Reports Server (NTRS)

    Calvert, W.; Tsintikidis, D.

    1990-01-01

    New, high-resolution spectrograms of the Voyager-2 radio observations at Uranus were produced from the original, six-second Planetary Radio Astronomy (PRA) data and these show a number of new features which were not obvious in previous versions. Among these new features are the detailed structure of the so-called broadband-bursty (b-bursty) emissions, unexpected sloping striations in the smooth high-frequency (SHF) component, and the overlap of these two components during the first rotation after closest approach. In addition, a slightly different planetary rotation rate from the b-bursty emissions, was found, and at the initial onset of the SHF component, what appears to be the shadow of a Uranian plasmasphere. These new spectrograms were prepared using a special dithering algorithm to show signal strengths as gray shadings, and the data were also manually cleaned to suppress noise and interference. This produced spectrograms of exceptional quality and certain details of their production on a stand-alone personal computer are also discussed.

  15. Voyager investigation of the cosmic diffuse background: Observations of rocket-studied locations with Voyager

    NASA Technical Reports Server (NTRS)

    Henry, Richard C.

    1994-01-01

    Attachments to this final report include 2 papers connected with the Voyager work: 'Voyager Observations of Dust Scattering Near the Coalsack Nebula' and 'Search for the Intergalactic Medium'. An appendix of 12 one-page write-ups prepared in connection with another program, UVISI, is also included. The one-page write-ups are: (1) Sky survey of UV point sources to 600 times fainter than previous (TD-1) survey; (2) Diffuse galactic light: starlight scattered from dust at high galactic latitude; (3) Optical properties of interstellar grains; (4) Fluorescence of molecular hydrogen in the interstellar medium; (5) Line emission from hot interstellar medium and/or hot halo of galaxy; (6) Integrated light of distant galaxies in the ultraviolet; (7) Intergalactic far-ultraviolet radiation field; (8) Radiation from recombining intergalactic medium; (9) Radiation from re-heating of intergalactic medium following recombination; (10) Radiation from radiative decay of dark matter candidates (neutrino, etc.); (11) Reflectivity of the asteroids in the Ultraviolet; and (12) Zodiacal light.

  16. From convicts to colonists: the health of prisoners and the voyage to Australia, 1823-53.

    PubMed

    Foxhall, Katherine

    2011-01-01

    From 1815, naval surgeons accompanied all convict voyages from Britain and Ireland to the Australian colonies. As their authority grew, naval surgeons on convict ships increasingly used their medical observations about the health of convicts to make pointed and sustained criticisms of British penal reforms. Beyond their authority at sea, surgeons' journals and correspondence brought debates about penal reform in Britain into direct conversation with debates about colonial transportation. In the 1830s, naval surgeons' claims brought them into conflict with their medical colleagues on land, as well as with the colonial governor, George Arthur. As the surgeons continued their attempts to combat scurvy, their rhetoric changed. By the late 1840s, as convicts' bodies betrayed the disturbing effects of separate confinement as they boarded the convict ships, surgeons could argue convincingly that the voyage itself was a space that could medically, physically and spiritually reform convicts. By the mid-1840s, surgeons took the role of key arbiters of convicts' potential contribution to the Australian colonies.

  17. From Convicts to Colonists: the Health of Prisoners and the Voyage to Australia, 1823 – 1853

    PubMed Central

    Foxhall, Katherine

    2012-01-01

    From 1815, naval surgeons accompanied all convict voyages from Britain and Ireland to the Australian colonies. As their authority grew, naval surgeons on convict ships increasingly used their medical observations about the health of convicts to make pointed and sustained criticisms of British penal reforms. Beyond their authority at sea, surgeons’ journals and correspondence brought debates about penal reform in Britain into direct conversation with debates about colonial transportation. In the 1830s, naval surgeons’ claims brought them into direct conflict with their medical colleagues on land, as well as with the colonial governor, George Arthur. As the surgeons continued their attempts to combat scurvy, their rhetoric changed. By the late 1840s, as convicts’ bodies betrayed the disturbing effects of separate confinement as they boarded the convict ships, surgeons could argue convincingly that the voyage itself was a space that could medically, physically, and spiritually reform convicts. By the mid 1840s, surgeons took the role of key arbiters of convicts’ potential contribution to the Australian colonies. PMID:21584986

  18. Magnetic field studies by voyager 2: preliminary results at saturn.

    PubMed

    Ness, N F; Acuna, M H; Behannon, K W; Burlaga, L F; Connerney, J E; Lepping, R P; Neubauer, F M

    1982-01-29

    Further studies of the Saturnian magnetosphere and planetary magnetic field by Voyager 2 have substantiated the earlier results derived from Voyager 1 observations in 1980. The magnetic field is primarily that of a centered dipole (moment = 0.21 gauss-RS(3); where one Saturn radius, RS, is 60,330 kilometers) tilted approximately 0.8 degrees from the rotation axis. Near closest approach to Saturn, Voyager 2 traversed a kronographic longitude and latitude range that was complementary to that of Voyager 1. Somewhat surprisingly, no evidence was found in the data or the analysis for any large-scale magnetic anomaly in the northern hemisphere which could be associated with the periodic modulation of Saturnian kilometric radiation radio emissions. Voyager 2 crossed the magnetopause of a relatively compressed Saturnian magnetosphere at 18.5 RS while inbound near the noon meridian. Outbound, near the dawn meridian, the magnetosphere had expanded considerably and the magnetopause boundary was not observed until the spacecraft reached 48.4 to 50.9 RS and possibly beyond. Throughout the outbound magnetosphere passage, a period of 46 hours (4.5 Saturn rotations), the field was relatively steady and smooth showing no evidence for any azimuthal asymmetry or magnetic anomaly in the planetary field. We are thus left with a rather enigmatic situation to understand the basic source of Saturnian kilometric radiation modulation, other than the small dipole tilt.

  19. Infrared observations of the saturnian system from voyager 2.

    PubMed

    Hanel, R; Conrath, B; Flasar, F M; Kunde, V; Maguire, W; Pearl, J; Pirraglia, J; Samuelson, R; Cruikshank, D; Gautier, D; Gierasch, P; Horn, L; Ponnamperuma, C

    1982-01-29

    During the passage of Voyager 2 through the Saturn system, infrared spectral and radiometric data were obtained for Saturn, Titan, Enceladus, Tethys, Iapetus, and the rings. Combined Voyager 1 and Voyager 2 observations of temperatures in the upper troposphere of Saturn indicate a seasonal asymmetry between the northern and southern hemispheres, with superposed small-scale meridional gradients. Comparison of high spatial resolution data from the two hemispheres poleward of 60 degrees latitude suggests an approximate symmetry in the small-scale structure, consistent with the extension of a symmetric system of zonal jets into the polar regions. Longitudinal variations of 1 to 2 K are observed. Disk- averaged infrared spectra of Titan show little change over the 9-month interval between Voyager encounters. By combining Voyager 2 temperature measurements with ground-based geometric albedo determinations, phase integrals of 0.91 +/- 0.13 and 0.89 +/- 0.09 were derived for Tethys and Enceladus, respectively. The subsolar point temperature of dark material on Iapetus must exceed 110 K. Temperatures (and infrared optical depths) for the A and C rings and for the Cassini division are 69 +/- 1 K (0.40 +/- 0.05), 85 +/- 1 K (0.10 +/- 0.03), and 85 +/- 2 K (0.07 +/- 0.04), respectively.

  20. Voyager 2 at neptune: imaging science results.

    PubMed

    Smith, B A; Soderblom, L A; Banfield, D; Barnet, C; Basilevsky, A T; Beebe, R F; Bollinger, K; Boyce, J M; Brahic, A; Briggs, G A; Brown, R H; Chyba, C; Collins, S A; Colvin, T; Cook, A F; Crisp, D; Croft, S K; Cruikshank, D; Cuzzi, J N; Danielson, G E; Davies, M E; De Jong, E; Dones, L; Godfrey, D; Goguen, J; Grenier, I; Haemmerle, V R; Hammel, H; Hansen, C J; Helfenstein, C P; Howell, C; Hunt, G E; Ingersoll, A P; Johnson, T V; Kargel, J; Kirk, R; Kuehn, D I; Limaye, S; Masursky, H; McEwen, A; Morrison, D; Owen, T; Owen, W; Pollack, J B; Porco, C C; Rages, K; Rogers, P; Rudy, D; Sagan, C; Schwartz, J; Shoemaker, E M; Showalter, M; Sicardy, B; Simonelli, D; Spencer, J; Sromovsky, L A; Stoker, C; Strom, R G; Suomi, V E; Synott, S P; Terrile, R J; Thomas, P; Thompson, W R; Verbiscer, A; Veverka, J

    1989-12-15

    Voyager 2 images of Neptune reveal a windy planet characterized by bright clouds of methane ice suspended in an exceptionally clear atmosphere above a lower deck of hydrogen sulfide or ammonia ices. Neptune's atmosphere is dominated by a large anticyclonic storm system that has been named the Great Dark Spot (GDS). About the same size as Earth in extent, the GDS bears both many similarities and some differences to the Great Red Spot of Jupiter. Neptune's zonal wind profile is remarkably similar to that of Uranus. Neptune has three major rings at radii of 42,000, 53,000, and 63,000 kilometers. The outer ring contains three higher density arc-like segments that were apparently responsible for most of the ground-based occultation events observed during the current decade. Like the rings of Uranus, the Neptune rings are composed of very dark material; unlike that of Uranus, the Neptune system is very dusty. Six new regular satellites were found, with dark surfaces and radii ranging from 200 to 25 kilometers. All lie inside the orbit of Triton and the inner four are located within the ring system. Triton is seen to be a differentiated body, with a radius of 1350 kilometers and a density of 2.1 grams per cubic centimeter; it exhibits clear evidence of early episodes of surface melting. A now rigid crust of what is probably water ice is overlain with a brilliant coating of nitrogen frost, slightly darkened and reddened with organic polymer material. Streaks of organic polymer suggest seasonal winds strong enough to move particles of micrometer size or larger, once they become airborne. At least two active plumes were seen, carrying dark material 8 kilometers above the surface before being transported downstream by high level winds. The plumes may be driven by solar heating and the subsequent violent vaporization of subsurface nitrogen.

  1. Reconstruction of the Voyager 2 Neptune Encounter in the ICRF System

    NASA Technical Reports Server (NTRS)

    Jacobson, Robert A.

    2008-01-01

    The Neptunian system was visited by the Voyager 2 spacecraft in August of 1989. We have re-examined the Voyager mission taking advantage of improvements made in dynamical and observational modelling and data processing.

  2. Energetic Particle Measurements from Voyager 1 in the Heliosheath Depletion Region and Voyager 2 in the Heliosheath

    NASA Astrophysics Data System (ADS)

    Decker, R. B.; Krimigis, S. M.; Roelof, E. C.; Hill, M. E.

    2013-12-01

    Voyager 1 (now at 125 AU, N35 deg. lat.) has been in the heliosheath depletion region since August 2012 while Voyager 2 (now at 101 AU, S30 deg. lat.) remains in the heliosheath proper. Measurements from the Voyager 1 LECP instrument taken in the depletion region are reviewed by S. M. Krimigis (this session). In the depletion region the intensities of charged particles of evidently heliospheric origin (suprathermal ions, ACRs, low-energy electrons) decreased while those of galactic origin (GCR ions and electrons) increased, and the magnetic field intensity increased but its direction remained close to that measured in the heliosheath. Entry into the main depletion region (> 2012 doy 238) was preceded by passage through two partial depletion regions during 2012 doy 210-215 and 2012 doy 226-234. In this presentation we discuss the evolution of angular distributions of energetic ions and protons measured at Voyager 1 from mid-2012 onward. We also discuss the variations of ion and electron intensities and angular distributions measured at Voyager 2 during the same period.

  3. Characteristics of the Termination Shock: Insights from Voyager

    SciTech Connect

    Cummings, A.C.; Stone, E.C.

    2005-08-01

    We examine the energy spectra obtained from the cosmic ray instrument on the Voyager 1 spacecraft during 2002/215 through 2005/60. We find that the energy spectra of protons below {approx}20 MeV often resemble two power laws with a relatively hard index at low energies and a softer index at higher energies. The point of intersection of the two power laws is {approx}3 MeV. Beginning in 2005, the low-energy index is typically -1.5, corresponding to a shock strength (compression ratio) of 2.5. We attribute these characteristics to a restricted region of the solar wind termination shock that is sporadically connected to the Voyager 1 spacecraft by the interplanetary magnetic field. The absence of significant spectral variability in 2005 suggests that Voyager 1 entered a region with minimal spatial gradients of the lowest energy ions.

  4. Recent Voyager Observations of the Interstellar Medium and Heliosheath

    NASA Astrophysics Data System (ADS)

    Richardson, John; Voyager Team

    2016-04-01

    Voyager 1 is now in the local interstellar medium (LISM) and Voyager 2 in the heliosheath. This talk will provide an overview of recent results from these two spacecraft. The LISM is a very dynamic region with disturbances apparently driven by solar events. Signatures of these disturbances in the LISM are an increase in cosmic rays intensities, a cosmic ray anisotropy, plasma wave and radio emissions, and a shock-like increase in the magnetic field. We will show examples of these events and discuss their origin. Voyager 2 is seeing very different flow and particle profiles in the heliosheath than V1 observed. We show the recent data and discuss the origin of these differences .

  5. In situ observations of interstellar plasma with Voyager 1.

    PubMed

    Gurnett, D A; Kurth, W S; Burlaga, L F; Ness, N F

    2013-09-27

    Launched over 35 years ago, Voyagers 1 and 2 are on an epic journey outward from the Sun to reach the boundary between the solar plasma and the much cooler interstellar medium. The boundary, called the heliopause, is expected to be marked by a large increase in plasma density, from about 0.002 per cubic centimeter (cm(-3)) in the outer heliosphere, to about 0.1 cm(-3) in the interstellar medium. On 9 April 2013, the Voyager 1 plasma wave instrument began detecting locally generated electron plasma oscillations at a frequency of about 2.6 kilohertz. This oscillation frequency corresponds to an electron density of about 0.08 cm(-3), very close to the value expected in the interstellar medium. These and other observations provide strong evidence that Voyager 1 has crossed the heliopause into the nearby interstellar plasma.

  6. Magnetic field studies at Jupiter by Voyager 2 - Preliminary results

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Acuna, M. H.; Lepping, R. P.; Burlaga, L. F.; Behannon, K. W.; Neubauer, F. M.

    1979-01-01

    The Voyager 2 magnetic field experiment, for which the instrumentation is identical to that on Voyager 1, operated flawlessly throughout the second Jupiter encounter. The paper presents a brief overview of the results obtained to date on the Jovian magnetosphere, the bow shock, the magnetopause, and the extended magnetic tail. The results and the magnetic field geometry confirm the earlier conclusion from Voyager 1 that Jupiter has an enormous magnetic tail, approximately 300-400 Jupiter radii in diameter, trailing behind the planet with respect to the supersonic flow of the solar wind. Additional observations of the distortion of the inner magnetosphere by a concentrated plasma show a spatial merging of the equatorial magnetodisk current with the current sheet in the magnetic tail. Disturbances near Ganymede are discussed.

  7. Plasma observations near saturn: initial results from voyager 2.

    PubMed

    Bridge, H S; Bagenal, F; Belcher, J W; Lazarus, A J; McNutt, R L; Sullivan, J D; Gazis, P R; Hartle, R E; Ogilvie, K W; Scudder, J D; Sittler, E C; Eviatar, A; Siscoe, G L; Goertz, C K; Vasyliunas, V M

    1982-01-29

    Results of measurements of plasma electrons and poitive ions made during the Voyager 2 encounter with Saturn have been combined with measurements from Voyager 1 and Pioneer 11 to define more clearly the configuration of plasma in the Saturnian magnetosphere. The general morphology is well represented by four regions: (i) the shocked solar wind plasma in the magnetosheath, observed between about 30 and 22 Saturn radii (RS) near the noon meridian; (ii) a variable density region between approximately 17 RS and the magnetopause; (iii) an extended thick plasma sheet between approximately 17 and approximately 7 RS symmetrical with respect to Saturn's equatorial plane and rotation axis; and (iv) an inner plasma torus that probably originates from local sources and extends inward from L approximately 7 to less than L approximately 2.7 (L is the magnetic shell parameter). In general, the heavy ions, probably O(+), are more closely confined to the equatorial plane than H(+), so that the ratio of heavy to light ions varies along the trajectory according to the distance of the spacecraft from the equatorial plane. The general configuration of the plasma sheet at Saturn found by Voyager 1 is confirmed, with some notable differences and additions. The "extended plasma sheet," observed between L approximately 7 and L approximately 15 by Voyager 1 is considerably thicker as observed by Voyager 2. Inward of L approximately 4, the plasma sheet collapses to a thin region about the equatorial plane. At the ring plane crossing, L approximately 2.7, the observations are consistent with a density of O(+) of approximately 100 per cubic centimeter, with a temperature of approximately 10 electron volts. The location of the bow shock and magnetopause crossings were consistent with those previously observed. The entire magnetosphere was larger during the outbound passage of Voyager 2 than had been previously observed; however, a magnetosphere of this size or larger is expected approximately 3

  8. Magnetic field studies by Voyager 1 - Preliminary results at Saturn

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Acuna, M. H.; Lepping, R. P.; Connerney, J. E. P.; Behannon, K. W.; Burlaga, L. F.; Neubauer, F. M.

    1981-01-01

    Confirmation and refinement of Saturnian magnetosphere features established by the Pioneer 11 emission are claimed for Voyager 1 magnetic field studies of the planet. The radius of the magnetopause at the subsolar point is 23 Saturn radii, and a magnetic tail of 80 Saturn radii diameter was discovered. The tail extends away from the sun and is similar to both type II comet tails and the terrestrial and Jovian magnetic tails. Data from Voyager's very close flyby of Titan, which is located within the Saturn magnetosphere, shows an absence of any substantial, intrinsic satellite magnetic field.

  9. The Voyager spacecraft /James Watt International Gold Medal Lecture/

    NASA Technical Reports Server (NTRS)

    Heacock, R. L.

    1980-01-01

    The Voyager Project background is reviewed with emphasis on selected features of the Voyager spacecraft. Investigations by the Thermo-electric Outer Planets Spacecraft Project are discussed, including trajectories, design requirements, and the development of a Self Test and Repair computer, and a Computer Accessed Telemetry System. The design and configuration of the spacecraft are described, including long range communications, attitude control, solar independent power, sequencing and control data handling, and spacecraft propulsion. The development program, maintained by JPL, experienced a variety of problems such as design deficiencies, and process control and manufacturing problems. Finally, the spacecraft encounter with Jupiter is discussed, and expectations for the Saturn encounter are expressed.

  10. Performance model of the Argonne Voyager multimedia server

    SciTech Connect

    Disz, T.; Olson, R.; Stevens, R.

    1997-07-01

    The Argonne Voyager Multimedia Server is being developed in the Futures Lab of the Mathematics and Computer Science Division at Argonne National Laboratory. As a network-based service for recording and playing multimedia streams, it is important that the Voyager system be capable of sustaining certain minimal levels of performance in order for it to be a viable system. In this article, the authors examine the performance characteristics of the server. As they examine the architecture of the system, they try to determine where bottlenecks lie, show actual vs potential performance, and recommend areas for improvement through custom architectures and system tuning.

  11. An early sophisticated East Polynesian voyaging canoe discovered on New Zealand's coast.

    PubMed

    Johns, Dilys A; Irwin, Geoffrey J; Sung, Yun K

    2014-10-14

    The colonization of the islands of East Polynesia was a remarkable episode in the history of human migration and seafaring. We report on an ocean-sailing canoe dating from close to that time. A large section of a complex composite canoe was discovered recently at Anaweka on the New Zealand coast. The canoe dates to approximately A.D. 1400 and was contemporary with continuing interisland voyaging. It was built in New Zealand as an early adaptation to a new environment, and a sea turtle carved on its hull makes symbolic connections with wider Polynesian culture and art. We describe the find and identify and radiocarbon date the construction materials. We present a reconstruction of the whole canoe and compare it to another early canoe previously discovered in the Society Islands.

  12. An early sophisticated East Polynesian voyaging canoe discovered on New Zealand's coast.

    PubMed

    Johns, Dilys A; Irwin, Geoffrey J; Sung, Yun K

    2014-10-14

    The colonization of the islands of East Polynesia was a remarkable episode in the history of human migration and seafaring. We report on an ocean-sailing canoe dating from close to that time. A large section of a complex composite canoe was discovered recently at Anaweka on the New Zealand coast. The canoe dates to approximately A.D. 1400 and was contemporary with continuing interisland voyaging. It was built in New Zealand as an early adaptation to a new environment, and a sea turtle carved on its hull makes symbolic connections with wider Polynesian culture and art. We describe the find and identify and radiocarbon date the construction materials. We present a reconstruction of the whole canoe and compare it to another early canoe previously discovered in the Society Islands. PMID:25267657

  13. An early sophisticated East Polynesian voyaging canoe discovered on New Zealand's coast

    PubMed Central

    Johns, Dilys A.; Irwin, Geoffrey J.; Sung, Yun K.

    2014-01-01

    The colonization of the islands of East Polynesia was a remarkable episode in the history of human migration and seafaring. We report on an ocean-sailing canoe dating from close to that time. A large section of a complex composite canoe was discovered recently at Anaweka on the New Zealand coast. The canoe dates to approximately A.D. 1400 and was contemporary with continuing interisland voyaging. It was built in New Zealand as an early adaptation to a new environment, and a sea turtle carved on its hull makes symbolic connections with wider Polynesian culture and art. We describe the find and identify and radiocarbon date the construction materials. We present a reconstruction of the whole canoe and compare it to another early canoe previously discovered in the Society Islands. PMID:25267657

  14. Galileo Regio Mosaic - Galileo over Voyager Data

    NASA Technical Reports Server (NTRS)

    1996-01-01

    A mosaic of four Galileo images of the Galileo Regio region on Ganymede (Latitude 18 N, Longitude: 149 W) is shown overlayed on the data obtained by the Voyager 2 spacecraft in 1979. North is to the top of the picture, and the sun illuminates the surface from the lower left, about 58 degrees above the horizon. The smallest features that can be discerned are about 80 meters (262 feet) in size in the Galileo images. These Galileo images show fine details of the dark terrain that makes up about half of the surface of the planet-sized moon. Ancient impact craters of various sizes and states of degradation testify to the great age of the terrain, dating back several billion years. The images reveal distinctive variations in albedo from the brighter rims, knobs, and furrow walls to a possible accumulation of dark material on the lower slopes, and crater floors. High photometric activity (large light contrast at high spatial frequencies) of this ice-rich surface was such that the Galileo camera's hardware data compressor was pushed into truncating lines. The north-south running gap between the left and right halves of the mosaic is a result of line truncation from the normal 800 samples per line to about 540. The images were taken on 27 June, 1996 Universal Time at a range of 7,580 kilometers (4,738 miles) through the clear filter of the Galileo spacecraft's imaging system. Launched in October 1989, Galileo entered orbit around Jupiter on December 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  15. 46 CFR 117.10 - Applicability to vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Applicability to vessels on an international voyage. 117.10 Section 117.10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER... international voyage. A vessel on an international voyage subject to the International Convention for Safety...

  16. 46 CFR 30.01-6 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Application to vessels on an international voyage. 30.01... PROVISIONS Administration § 30.01-6 Application to vessels on an international voyage. (a) Except as provided... vessel on an international voyage apply to a vessel that: (1) Is mechanically propelled and of at...

  17. Voyager 2 Test Of The Radar Time-Delay Effect

    NASA Technical Reports Server (NTRS)

    Krisher, Timothy P.; Anderson, John D.; Taylor, Anthony H.

    1993-01-01

    Report presents analysis of radio range measurements generated during superior solar conjunction of Voyager 2 spacecraft in December 1985. One in continuing series of studies directed toward verifying prediction, according to theory of general relativity, that electromagnetic signal propagating near Sun is delayed by solar gravitational field.

  18. Plasma observations near neptune: initial results from voyager 2.

    PubMed

    Belcher, J W; Bridge, H S; Bagenal, F; Coppi, B; Divers, O; Eviatar, A; Gordon, G S; Lazarus, A J; McNutt, R L; Ogilvie, K W; Richardson, J D; Siscoe, G L; Sittler, E C; Steinberg, J T; Sullivan, J D; Szabo, A; Villanueva, L; Vasyliunas, V M; Zhang, M

    1989-12-15

    The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.

  19. Plasma observations near jupiter: initial results from voyager 2.

    PubMed

    Bridge, H S; Belcher, J W; Lazarus, A J; Sullivan, J D; Bagenal, F; McNutt, R L; Ogilvie, K W; Scudder, J D; Sittler, E C; Vasyliunas, V M; Goertz, C K

    1979-11-23

    The first of at least nine bow shock crossings observed on the inbound pass of Voyager 2 occurred at 98.8 Jupiter radii (R(J)) with final entry into the magnetosphere at 62 R(J). On both the inbound and outbound passes the plasma showed a tendency to move in the direction of corotation, as was observed on the inbound pass of Voyager 1. Positive ion densities and electron intensities observed by Voyager 2 are comparable within a factor of 2 to those seen by Voyager 1 at the same radial distance from Jupiter; the composition of the magnetospheric plasma is again dominated by heavy ions with a ratio of mass density relative to hydrogen of about 100/1. A series of dropouts of plasma intensity near Ganymede may be related to a complex interaction between Ganymede and the magnetospheric plasma. From the planetary spin modulation of the intensity of plasma electrons it is inferred that the plasma sheet is centered at the dipole magnetic equator out to a distance of 40 to 50 R(J) and deviates from it toward the rotational equator at larger distances. The longitudinal excursion of the plasma sheet lags behind the rotating dipole by a phase angle that increases with increasing radial distance.

  20. Changes around Marduk between Voyager, and Galileo's first two orbits

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Detail of changes around Marduk on Jupiter's moon Io as seen by Voyager 1 in 1979 (upper left) and NASA's Galileo spacecraft between June 1996 (lower left) and September 1996 (upper and lower right). The new dark red linear feature extending southeast from Marduk is about 250 kilometers long and may be a volcanic fissure. The flow-like feature at the bottom of the images is distinct in the Voyager data, indistinct in the June Galileo data, but distinct again in the September Galileo data. This may be due to the different lighting conditions rather than volcanic activity. The Voyager 1 image uses the green, blue, and violet filters. The upper right September 1996 image from Galileo uses the violet and green filters of the solid state imaging system aboard the Galileo spacecraft and a synthetic blue to simulate Voyager colors. The lower June and September, 1996 Galileo images use the imaging system's near-infrared (756 nm), green, and violet filters. North is to the top in all frames.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  1. Plasma observations near Neptune: Initial results for Voyager 2

    SciTech Connect

    Belcher, J.W.; Bridge, H.S.; Coppi, B.; Gordon, G.S. Jr.; Lazarus, A.J.; McNutt, R.L. Jr.; Richardson, J.D.; Steinberg, J.T.; Sullivan, A.; Szabo, A.; Villanueva, L.; Zhang, M. ); Bagenal, F. ); Divers, O. ); Ogilvie, K.W.; Sittler, E.C. Jr. ); Siscoe, G.L. ); Eviatar, A. ); Vasyliunas, V.M. )

    1989-12-15

    The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.

  2. Magnetic field studies by Voyager 2 - Preliminary results at Saturn

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Acuna, M. H.; Behannon, K. W.; Burlaga, L. F.; Connerney, J. E. P.; Lepping, R. P.; Neubauer, F. M.

    1982-01-01

    Results of Voyager 2 studies of the magnetosphere and planetary magnetic field of Saturn are presented. Magnetometer studies have confirmed the results obtained by Voyager 1, indicating the magnetic field to be that of a centered dipole of moment 0.21 gauss Saturn radii-cubed, tilted approximately 0.8 deg from the rotation axis and a maximum measured field intensity of 1187 nT at latitude 17.3 deg N just before periapsis. Voyager 2 observed multiple bow shock and magnetopause crossings during its inbound and outbound trajectories, which were complementary to those of Voyager 1, including magnetopause crossing at 18.5 Saturn radii on the inbound trajectory, and at 48.4-50.9 Saturn radii outbound indicative of magnetospheric expansion due to changing solar wind conditions. Throughout the outbound passage, the magnetospheric field was observed to be relatively steady and smooth, with no evidence for any azimuthal asymmetry or magnetic anomaly. Results thus are incapable of accounting for the observed periodic modulation of the Saturnian kilometric radio emissions.

  3. Introducing Students to Darwin via the Voyage of HMS "Beagle"

    ERIC Educational Resources Information Center

    Swab, Janice C.

    2010-01-01

    I use the diary that Darwin wrote during the voyage of HMS Beagle and recent images of a few of the places he visited to illustrate some comparisons between Darwin's world and ours. For today's students, increasingly committed to environmental issues, this may be an especially promising way to introduce Darwin.

  4. Voyages of Discovery: Experiencing the Emotion of History

    ERIC Educational Resources Information Center

    Kelin, Daniel A., II

    2005-01-01

    Guiding students through a dramatic exploration of an historical event can elicit strong emotional reactions that can deepen student understanding and interest in the subject matter. This article describes an integrated third grade lesson plan that focuses on Henry Hudson's voyages in the early 1600s. The students take on the roles of Hudson's…

  5. Voyager observations of jupiter's distant magnetotail. Progress report

    SciTech Connect

    Kurth, W.S.; Gurnett, D.A.; Scarf, F.L.; Poynter, R.L.; Sullivan, J.D.

    1980-08-01

    Observations of nonthermal continuum radiation by Voyager 1 and 2 at large distances from Jupiter have led to the identification of brief encounters with the Jovian magnetosphere at distances greater than 700 RJ and in directions substantially far from the Jupiter-Sun line. In addition, a number of examples of continuum radiation apparently trapped in local density depressions in the solar wind are observed. Simultaneous measurements by the Voyager plasma instrument have verified the distant magnetotail crossings and are used to correlate the occurrence of trapped continuum radiation events within solar wind density rarefractions. The Voyager observations of the distant Jovian magnetotail are compared with observations in the distant terrestrial magnetosphere and also with observations of the plasma tails of comets. One variable explanation of the observations is that the Jovian tail consists of filamentary structures, some of which extend to large distances in the pre-dawn direction. The observations of continuum radiation trapped in low-density regions of the solar wind suggest that Voyager may at times be connected to the distant tail by a low-density trough which acts as a wave guide and allows radiation from the tail to reach the spacecraft. This may provide an indirect method of detecting the tail extending more than 2 AU downstream from Jupiter.

  6. The Voyages of Columbus: A Turning Point in World History.

    ERIC Educational Resources Information Center

    Crosby, Alfred W.; Nader, Helen

    The far-reaching and transforming interactions of the Old World and the New are known today as "the Columbian Exchange." Part 1 of this booklet is an introduction by John J. Patrick dealing with teaching about the voyages of Christopher Columbus. Part 2, "Columbus and Ecological Imperialism," by Alfred W. Crosby, provides an ecological perspective…

  7. Overview of the Voyager ultraviolet spectrometry results through Jupiter encounter

    NASA Technical Reports Server (NTRS)

    Broadfoot, A. L.; Sandel, B. R.; Shemansky, D. E.; Smith, G. R.; Holberg, J. B.; Mcconnell, J. C.; Atreya, S. K.; Donahue, T. M.; Strobel, D. F.; Bertaux, J. L.

    1981-01-01

    The observations of a number of objects by the Voyager EUV instruments are summarized. The summary is considered to demonstrate the wide ranging application of the EUV spectroscopy. It also marks an important step forward in spectrography and emphasizes the continuing importance of the search and discovery nature of spectroscopic techniques.

  8. The Voyager 2 Encounter with the Uranian System.

    ERIC Educational Resources Information Center

    Stone, E. C.; Miner, E. D.

    1986-01-01

    A series of 12 reports on the Voyager Two experiments in the Uranian system. Reports are included on: (1) imaging science; (2) photometry; (3) infrared; (4) ultraviolet; (5) radio science; (6) magnetic fields; (7) plasma; (8) charged particles; (9) magnetosphere (hot plasma and radiation); (10) radion observations; and (11) plasma waves. An…

  9. A voyage to Mars: space radiation, aging, and nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On exploratory class missions, such as a voyage to Mars, astronauts will be exposed to doses and types of radiation that are not experienced in low earth orbit where the space shuttle and International Space Station operate. Astronauts who participate in exploratory class missions outside the magne...

  10. A Curriculum Review: The Voyage of the Mimi.

    ERIC Educational Resources Information Center

    Johns, Kenneth W.

    1988-01-01

    The curriculum package, "The Voyage of the Mimi," uses computer, videocassette, student text, and workbook for integrated study of the great whales and the impact of social actions on society and the environment. This review suggests that the package also offers many ancillary teaching opportunities. (CB)

  11. Flight performance of the Voyager electrical power system

    SciTech Connect

    Packard, L.A.

    1981-01-01

    In this paper the Voyager power subsystem is described, and its flight performance to date is discussed. Of particular interest are the performance of the primary power source radioisotope thermoelectric generators (RTGs), the autonomous operation features of the power system, and the load management strategy.

  12. Voyages Through Time: Integrated science for high schools, Pamela Harman

    NASA Astrophysics Data System (ADS)

    Harman, Pamela; Devore, Edna

    Investigating the origin and evolution of the universe and life is a compelling theme for teaching science. It engages students in the key questions about change and the evidence for change over time, and offers a unifying theme for integrated science. "Voyages Through Time" is a high school integrated science curriculum on the theme of evolution. Six modules comprise the year-long course: Cosmic Evolution, Planetary Evolution, Origin of Life, Evolution of Life, and Evolution of Technology. A brief overview of the curriculum is presented. Participants conduct one or two activities representative of the six modules. Each workshop participant receives a sampler CD-ROM with a comprehensive overview of the curriculum, standards, and resources including complete lessons for use in the classroom. "Voyages Through Time" is being developed by a US team of scientists, educators, writers, and classroom teachers and students led by the SETI Institute partnered with NASA Ames Research Center, California Academy of Sciences and San Francisco State University. In 2000-2001 school year, "Voyages Through Time" was pilot tested (trialed) in high school classrooms in the San Francisco Bay Area, California. Following revisions, the curriculum was field tested (trialed) in 28 US states in more than 90 schools August 2001-June 2002. The final version is expected to be ready for publication by the beginning of 2003. "Voyages Through Time" is funded by the National Science Foundation (IMD # 9730693), NASA Astrobiology Institute, NASA Fundamental Biology, The Foundation for Microbiology, Educate America, and the Hewlett-Packard Company.

  13. Voyager: The grandest tour. The mission to the outer planets

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A history and general accomplishments of the Voyager 1 and 2 missions to the outer planets are presented. Over the course of 12 years, these spacecraft drew back the curtain on nearly half the solar system. They brought into sharp focus the faces of the four giant outer planets - Jupiter, Saturn, Uranus, and Neptune - and their families of disparate moons. The Voyagers showed us unimagined worlds: frozen beauty in the rings of Saturn, and molten violence in the explosive sulfur volcanoes on Jupiter's moon Io. They brought us close-ups of the florid and intricate storms of Jupiter itself. Voyager 2 went on to reveal the peculiarities of cockeyed Uranus and its equally skewed rings and moons. Then finally, Neptune, nearly invisible from earth, was unveiled in all its big, blue splendor, circled by shadowy rings and a bright pastel moon called Triton. Both Voyagers are headed toward the outer boundary of the solar system in search of the heliopause, the region where the sun's influence wanes and the beginning of interstellar space can be sensed.

  14. Voyager: The grandest tour. The mission to the outer planets

    NASA Astrophysics Data System (ADS)

    1991-04-01

    A history and general accomplishments of the Voyager 1 and 2 missions to the outer planets are presented. Over the course of 12 years, these spacecraft drew back the curtain on nearly half the solar system. They brought into sharp focus the faces of the four giant outer planets - Jupiter, Saturn, Uranus, and Neptune - and their families of disparate moons. The Voyagers showed us unimagined worlds: frozen beauty in the rings of Saturn, and molten violence in the explosive sulfur volcanoes on Jupiter's moon Io. They brought us close-ups of the florid and intricate storms of Jupiter itself. Voyager 2 went on to reveal the peculiarities of cockeyed Uranus and its equally skewed rings and moons. Then finally, Neptune, nearly invisible from earth, was unveiled in all its big, blue splendor, circled by shadowy rings and a bright pastel moon called Triton. Both Voyagers are headed toward the outer boundary of the solar system in search of the heliopause, the region where the sun's influence wanes and the beginning of interstellar space can be sensed.

  15. Voyager 1 and 2 Atlas of Six Saturnian Satellites

    NASA Technical Reports Server (NTRS)

    Batson, R. M.

    1984-01-01

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

  16. [The corvette "Nordstjernen's" voyage to the opening of the Suez Canal--naval medicine in 1869].

    PubMed

    Ongre, Aksel; Pettersen, Jan Sommerfelt; Munch, Johan Storm

    2002-06-30

    When the Norwegian corvette Nordstjernen was in the North Sea bound for Port Said to be present at the opening of the Suez Canal on 17 November 1869, an officer suffered a rupture of m. triceps brachii when he was drawn into the machinery during a storm. He was put ashore in Harwich; four days after the injury he was hospitalized in Colchester. The voyage was eventful in other ways too. Another officer died from typhoid fever in Ismailia. On the Swedish frigate Vanadis, also present at the opening of the Suez Canal, one of the doctors died from lung infection and was buried in Smyrna; a twelve-feet high column of white marble was taken from the ruins of Aesculap's temple and put on his grave. Denmark was represented by the frigate Sjaelland. During a storm in the North Sea, one seaman fell down on the deck from the foresail yard and suffered contusions and a fracture of the left clavicle. These cases illustrate challenges that faced our ancestors. The accident happened when the ship was in the Netherlands sector of the North Sea as we know it today. Today the Coast Guard could have arranged transport by helicopter and hospitalized the patient in about two hours.

  17. [The corvette "Nordstjernen's" voyage to the opening of the Suez Canal--naval medicine in 1869].

    PubMed

    Ongre, Aksel; Pettersen, Jan Sommerfelt; Munch, Johan Storm

    2002-06-30

    When the Norwegian corvette Nordstjernen was in the North Sea bound for Port Said to be present at the opening of the Suez Canal on 17 November 1869, an officer suffered a rupture of m. triceps brachii when he was drawn into the machinery during a storm. He was put ashore in Harwich; four days after the injury he was hospitalized in Colchester. The voyage was eventful in other ways too. Another officer died from typhoid fever in Ismailia. On the Swedish frigate Vanadis, also present at the opening of the Suez Canal, one of the doctors died from lung infection and was buried in Smyrna; a twelve-feet high column of white marble was taken from the ruins of Aesculap's temple and put on his grave. Denmark was represented by the frigate Sjaelland. During a storm in the North Sea, one seaman fell down on the deck from the foresail yard and suffered contusions and a fracture of the left clavicle. These cases illustrate challenges that faced our ancestors. The accident happened when the ship was in the Netherlands sector of the North Sea as we know it today. Today the Coast Guard could have arranged transport by helicopter and hospitalized the patient in about two hours. PMID:12555606

  18. Meteorological Implications of the First Voyage of Christopher Columbus.

    NASA Astrophysics Data System (ADS)

    Cerveny, Randall S.; Hobgood, Jay S.

    1992-02-01

    The log of the first voyage of Christopher Columbus to the New World provides valuable information on the meteorological conditions of September 1492. Comparison and analysis of the descriptive accounts of weather made by Columbus and his pilots to other available Columbian and modern data leads to two distinct perspectives on the Columbian voyage: an examination of the frequency of "calm" events, and an analysis of the lack of tropical storm activity. The major conclusions of the first portion of the study include: 1) The Columbian pilots' descriptions of "cairns" related to travel slower than travel occurring during other portions of the voyage. That rate of travel compares favorably to calm winds and an oceanic current of 0.4 knots, a value close to modern-day values; 2) The frequency of "calm" events experienced by Christopher Columbus in 1492 is significantly higher than the most liberal estimates of calms in the North Atlantic over the last 100 years; and 3) The locations of the Columbian calms are generally in the same region currently experiencing the highest frequency of calms. The main finding of the second portion of the study is that, based on historical hurricane records from 1886 to 1989, the center of a hurricane would have passed within 100 km of Columbus only once in the past 104 years. Inclusion of tropical storms increases this number to four out of 104 years. Therefore, while Columbus may indeed have been fortunate to have avoided severe weather during his voyage, the odds decidedly were in his favor. This Columbian "weather luck" was due to a combination of 1) encountering abnormally strong anticyclonic flow over the eastern North Atlantic, 2) starting late enough in the hurricane season to significantly decrease the probability of experiencing a hurricane, and 3) taking a north and easterly voyage, thereby avoiding the area of maximum hurricane occurrence.

  19. Perspectives on More Than 3 Decades of the Voyager Mission

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-05-01

    Voyager 1 and Voyager 2, twin NASA probes that were launched from Cape Canaveral, Fla., in the summer of 1977 during a once-every-175-year alignment of the solar system's giant outer planets, changed our understanding about those planets—Jupiter, Saturn, Uranus, and Neptune—as well as the 4 dozen moons the spacecraft have flown by and the shape of the solar system itself. Today these 722-kilogram probes, whose instruments mostly are still operating after almost 34 years in space, are helping to rewrite the textbooks about the outer edge of our solar system as they continue to race outward from Earth. Voyager 1, currently 17.4 billion kilometers from Earth, and Voyager 2, 14.2 billion kilometers from Earth, are on their way to becoming the first human-made objects to leave the solar system and enter interstellar space, the medium between stars. In exclusive interviews with Eos and during a 27 April news briefing at NASA headquarters in Washington, D. C., Voyager project scientist Ed Stone and several others who have worked on the project discussed mission highlights and the probes' journeys through the heliosheath. This is the final outer layer of a kind of bubble the Sun creates around itself called the heliosphere, a margin where the solar wind is slowed by the pressure of interstellar gas. All the while, the spacecraft, still responsive to ground commands, are sending back data about the solar wind, the magnetic field carried out by the wind, charged particles, and plasma waves.

  20. The heliosphere neutrals composition: from Voyager UVS to IMAPS

    NASA Astrophysics Data System (ADS)

    Ben-Jaffel, L.

    2015-12-01

    For the last 35 years, the Voyagers (V) 1 and 2 ultraviolet spectrometers (UVS) data harvest has covered heliosphere sky-background in-situ measurements, stellar spectrophotometry, and outer planets encounters. Their long and ongoing operation period overlaps with many current and past ultraviolet missions, offering unique opportunities for cross-calibration with other spectrometers. Here we revisit the Voyager UVS calibration to assess the intriguing 243% (V1) and 156% (V2) sensitivity enhancements recently proposed. Using the Saturn Lyman-α airglow, observed in-situ by both Voyagers, and remotely by IUE, we match the Voyager values to IUE, taking into account the shape of the Saturn and sky-background Lyman-α lines observed with the Goddard High Resolution Spectrograph onboard the Hubble Space Telescope. For all known ranges of the interplanetary H I density, we show that the V1 and V2 UVS sensitivities at the Lyman-α channels cannot be enhanced by the amounts thus far proposed. Our prescription is to keep the original calibration of the Voyager UVS with an uncertainty that should not exceed 30%, making both instruments some of the most stable EUV/FUV spectrographs of the history of space exploration. This rich heritage from past and current space missions confirms that UV observations of the sky-background are a powerful lever for constraining the neutral composition and large structure of the heliosphere. It also points to the need in the future for fine Doppler-shift measurements and faint emissions detection in order to directly access the microphysical processes that drive the instant shape and composition of the heliosphere that is forced by the magnetized plasmas from solar wind and the local interstellar medium. Future deep space missions should thus include UV capabilities that make use of sensitive, high-resolution technology that allows achieving the highest throughput for extended light sources.

  1. COMPARISON OF PIONEER 10, VOYAGER 1, AND VOYAGER 2 ULTRAVIOLET OBSERVATIONS WITH ANTI-SOLAR LYMAN-ALPHA BACKSCATTER SIMULATIONS

    SciTech Connect

    Fayock, B.; Zank, G. P.; Heerikhuisen, J. E-mail: garyp.zank@gmail.com

    2013-09-20

    Observations made by ultraviolet (UV) detectors on board Pioneer 10, Voyager 1, and Voyager 2 can be used to analyze the distribution of neutral hydrogen throughout the heliosphere, including the interaction regions of the solar wind and local interstellar medium. Previous studies of the long-term trend of decreasing intensity with increasing heliocentric distance established the need for more sophisticated heliospheric models. Here we use state-of-the-art three-dimensional (3D) magnetohydrodynamic (MHD) neutral models to simulate Lyman-alpha backscatter as would be seen by the three spacecrafts, exploiting a new 3D Monte Carlo radiative transfer code under solar minimum conditions. Both observations and simulations of the UV backscatter intensity are normalized for each spacecraft flight path at {approx}15 AU, and we focus on the slope of decreasing intensity over an increasing heliocentric distance. Comparisons of simulations with Voyager 1 Lyman-alpha data results in a very close match, while the Pioneer 10 comparison is similar due to normalization, but not considered to be in agreement. The deviations may be influenced by a low resolution of photoionization in the 3D MHD-neutral model, a lack of solar cycle activity in our simulations, and possibly issues with instrumental sensitivity. Comparing the slope of Voyager 2 and the simulated intensities yields an almost identical match. Our results predict a large increase in the Lyman-alpha intensity as the hydrogen wall is approached, which would signal an imminent crossing of the heliopause.

  2. Farewell to the Voyagers: Measuring the Local ISM in the Immediate Path of the Two Voyager Spacecraft

    NASA Astrophysics Data System (ADS)

    Redfield, Seth

    2014-10-01

    Astronomical observations of the interstellar medium often struggle to measure fundamental physical properties of the gas on small scales because most observations are averaged along the line of sight, leading to difficulties in evaluating pressure equilibrium, turbulence, magnetic field structure, and volume density. The local ISM has helped in this regard by providing relatively simple ISM absorption profiles over short path lengths, with low column densities only detectable with strong transitions in the UV . On August 25, 2012, the first human-made object, the Voyager 1 spacecraft, crossed the heliosphere, effectively leaving the solar system and entering the galactic interstellar environment. Voyager 2 is expected to do the same in the coming years, and over the next decade both spacecraft will continue to make daily measurements of fundamental physical properties. We propose to make the first observations of nearby stars along the same line of sight as the current locations of the Voyager spacecraft in order to measure the same interstellar material. The proposed observations are of the very closest stars in these directions and will provide measurements of the kinematic structure, electron density, temperature and turbulence, elemental abundances and small scale structure by comparing two closely spaced sight lines. With both HST and the Voyager spacecraft approaching the end of long and fruitful missions, we have the opportunity to acquire a unique dataset which synthesizes the independent and complimentary in situ observations with the shortest possible line-of-sight observations, to provide an unprecedented study of the galactic ISM surrounding the Sun.

  3. Cinnarizine for Sea Sickness During a Remote Pacific Ocean Rescue Mission.

    PubMed

    Lyon, Regan F; Rush, Stephen C; Roland, J Thomas; Jethanamest, Daniel; Schwan, Christopher P; Kharon, Chetan U

    2015-01-01

    Motion sickness can be a limiting factor for sea and air missions. We report the experience of a Pararescue (PJ) team on a Pacific Ocean rescue mission in which motion sickness was prevalent. Cinnarizine, an antagonist of H1-histamine receptors, was used to treat affected PJs. We also report findings of a survey of PJs regarding motion sickness. A family of four on a disabled sailboat 900 miles off the coast of Mexico sent out a distress call because their 1-year-old daughter became severely ill with fever and diarrhea. Four PJs were deployed on a C-130, performed a free-fall parachute insertion into the ocean, and boarded the sailboat. All four PJs experienced onset of motion sickness at some point during the early part of the mission and symptoms persisted through the first 24 hours. Three PJs experienced ongoing nausea, vomiting, dizziness, and sensory imbalances. The captain of the sailboat offered the three sick PJs approximately 18mg of cinnarizine two or three times a day with relief of symptoms and improvement on operational effectiveness. A new, anonymous, voluntary survey of Air National Guard PJs and combat rescue officers revealed that 78.4% of Operators have experienced motion sickness at sea. We discuss the current theories on motion sickness, the effect of motion sickness on operational effectiveness, and research on treatment of motion sickness, including the medication cinnarizine.

  4. Cinnarizine for Sea Sickness During a Remote Pacific Ocean Rescue Mission.

    PubMed

    Lyon, Regan F; Rush, Stephen C; Roland, J Thomas; Jethanamest, Daniel; Schwan, Christopher P; Kharon, Chetan U

    2015-01-01

    Motion sickness can be a limiting factor for sea and air missions. We report the experience of a Pararescue (PJ) team on a Pacific Ocean rescue mission in which motion sickness was prevalent. Cinnarizine, an antagonist of H1-histamine receptors, was used to treat affected PJs. We also report findings of a survey of PJs regarding motion sickness. A family of four on a disabled sailboat 900 miles off the coast of Mexico sent out a distress call because their 1-year-old daughter became severely ill with fever and diarrhea. Four PJs were deployed on a C-130, performed a free-fall parachute insertion into the ocean, and boarded the sailboat. All four PJs experienced onset of motion sickness at some point during the early part of the mission and symptoms persisted through the first 24 hours. Three PJs experienced ongoing nausea, vomiting, dizziness, and sensory imbalances. The captain of the sailboat offered the three sick PJs approximately 18mg of cinnarizine two or three times a day with relief of symptoms and improvement on operational effectiveness. A new, anonymous, voluntary survey of Air National Guard PJs and combat rescue officers revealed that 78.4% of Operators have experienced motion sickness at sea. We discuss the current theories on motion sickness, the effect of motion sickness on operational effectiveness, and research on treatment of motion sickness, including the medication cinnarizine. PMID:26125158

  5. Extreme ultraviolet observations from voyager 2 encounter with jupiter.

    PubMed

    Sandel, B R; Shemansky, D E; Broadfoot, A L; Bertaux, J L; Blamont, J E; Belton, M J; Ajello, J M; Holberg, J B; Atreya, S K; Donahue, T M; Moos, H W; Strobel, D F; McConnell, J C; Dalgarno, A; Goody, R; McElroy, M B; Takacs, P Z

    1979-11-23

    Extreme ultraviolet spectral observations of the Jovian planetary system made during the Voyager 2 encounter have extended our knowledge of many of the phenomena and physical processes discovered by the Voyager 1 ultraviolet spectrometer. In the 4 months between encounters, the radiation from Io's plasma torus has increased in intensity by a factor of about 2. This change was accompanied by a decrease in plasma temperature of about 30 percent. The high-latitude auroral zones have been positively associated with the magnetic projection of the plasma torus onto the planet. Emission in molecular hydrogen bands has been detected from the equatorial regions of Jupiter, indicating planetwide electron precipitation. Hydrogen Lyman alpha from the dark side of the planet has been measured at an intensity of about 1 kilorayleigh. An observation of the occultation of alpha Leonis by Jupiter was carried out successfully and the data are being analyzed in detail.

  6. The galilean satellites and jupiter: voyager 2 imaging science results.

    PubMed

    Smith, B A; Soderblom, L A; Beebe, R; Boyce, J; Briggs, G; Carr, M; Collins, S A; Cook, A F; Danielson, G E; Davies, M E; Hunt, G E; Ingersoll, A; Johnson, T V; Masursky, H; McCauley, J; Morrison, D; Owen, T; Sagan, C; Shoemaker, E M; Strom, R; Suomi, V E; Veverka, J

    1979-11-23

    Voyager 2, during its encounter with the Jupiter system, provided images that both complement and supplement in important ways the Voyager 1 images. While many changes have been observed in Jupiter's visual appearance, few, yet significant, changes have been detected in the principal atmospheric currents. Jupiter's ring system is strongly forward scattering at visual wavelengths and consists of a narrow annulus of highest particle density, within which is a broader region in which the density is lower. On Io, changes are observed in eruptive activity, plume structure, and surface albedo patterns. Europa's surface retains little or no record of intense meteorite bombardment, but does reveal a complex and, as yet, little-understood system of overlapping bright and dark linear features. Ganymede is found to have at least one unit of heavily cratered terrain on a surface that otherwise suggests widespread tectonism. Except for two large ringed basins, Callisto's entire surface is heavily cratered.

  7. Plasma observations near jupiter: initial results from voyager 1.

    PubMed

    Bridge, H S; Belcher, J W; Lazarus, A J; Sullivan, J D; McNutt, R L; Bagenal, F; Scudder, J D; Sittler, E C; Siscoe, G L; Vasyliunas, V M; Goertz, C K; Yeates, C M

    1979-06-01

    Extensive measurements of low-energy positive ions and electrons were made throughout the Jupiter encounter of Voyager 1. The bow shock and magneto-pause were crossed several times at distances consistent with variations in the upstream solar wind pressure measured on Voyager 2. During the inbound pass, the number density increased by six orders of magnitude between the innermost magnetopause crossing at approximately 47 Jupiter radii and near closest approach at approximately 5 Jupiter radii; the plasma flow during this period was predominately in the direction of corotation. Marked increases in number density were observed twice per planetary rotation, near the magnetic equator. Jupiterward of the Io plasma torus, a cold, corotating plasma was observed and the energylcharge spectra show well-resolved, heavy-ion peaks at mass-to-charge ratios A/Z* = 8, 16, 32, and 64.

  8. Neptune's Wind Speeds Obtained by Tracking Clouds in Voyager Images.

    PubMed

    Hammel, H B; Beebe, R F; De Jong, E M; Hansen, C J; Howell, C D; Ingersoll, A P; Johnson, T V; Limaye, S S; Magalhaes, J A; Pollack, J B; Sromovsky, L A; Suomi, V E; Swift, C E

    1989-09-22

    Images of Neptune obtained by the narrow-angle camera of the Voyager 2 spacecraft reveal large-scale cloud features that persist for several months or longer. The features' periods of rotation about the planetary axis range from 15.8 to 18.4 hours. The atmosphere equatorward of -53 degrees rotates with periods longer than the 16.05-hour period deduced from Voyager's planetary radio astronomy experiment (presumably the planet's internal rotation period). The wind speeds computed with respect to this radio period range from 20 meters per second eastward to 325 meters per second westward. Thus, the cloud-top wind speeds are roughly the same for all the planets ranging from Venus to Neptune, even though the solar energy inputs to the atmospheres vary by a factor of 1000.

  9. VOYAGER 2 OBSERVES A LARGE DENSITY INCREASE IN THE HELIOSHEATH

    SciTech Connect

    Richardson, J. D.; Wang, C. E-mail: cw@spaceweather.ac.cn

    2012-11-01

    Voyager 2 (V2) entered the heliosheath in 2007 August at roughly the same time solar minimum conditions were reaching the outer heliosphere. Soon after crossing the termination shock the solar wind density at Voyager decreased by a factor of two and the temperature decreased by a factor of three. At the beginning of 2011 the plasma density in the heliosheath began to increase and in mid-2012 it was up by more than a factor of two. The temperature rose by about 50% and the speed remained constant, although the flow direction continues to turn tailward. These changes may signal the end of solar minimum conditions at V2 in the heliosheath, although we do not understand why the speed did not decrease. The increased dynamic pressure has lead to an outward movement of the termination shock from its very compressed state at solar minimum.

  10. The jovian nebula: a post-voyager perspective.

    PubMed

    Trauger, J T

    1984-10-19

    Voyager 1 carried a diverse collection of magnetospheric probes through the inner Jovian magnetosphere in March 1979. The ensuing data analysis and theoretical investigation provided a comprehensive description of the Jovian nebula, a luminous torus populated with newly released heavy ions drawn from Io's surface. Recent refinements in Earth-based imaging instrumentation are used to extend the Voyager in situ picture in temporal and spatial coverage. An analysis of [SIII] and [SII] optical emissions observed during the Jovian apparitions of 1981 through 1983 reveals three distinct torus components. Regularities have been identified in the ion partitioning and ion densities in the hot outer and inner tori, sharply defined radial structure is found in the plasma near Io, and the relative permanence of the cool inner torus is inferred. An extended cloud of neutral material is required as a source of fresh ions in the nebula.

  11. The galilean satellites and Jupiter: Voyager 2 imaging science results

    USGS Publications Warehouse

    Smith, B.A.; Soderblom, L.A.; Beebe, R.; Boyce, J.; Briggs, G.; Carr, M.; Collins, S.A.; Cook, A.F.; Danielson, G.E.; Davies, M.E.; Hunt, G.E.; Ingersoll, A.; Johnson, T.V.; Masursky, H.; McCauley, J.; Morrison, D.; Owen, editors, Timothy W.; Sagan, C.; Shoemaker, E.M.; Strom, R.; Suomi, V.E.; Veverka, J.

    1979-01-01

    Voyager 2, during its encounter with the Jupiter system, provided images that both complement and supplement in important ways the Voyager 1 images. While many changes have been observed in Jupiter's visual appearance, few, yet significant, changes have been detected in the principal atmospheric currents. Jupiter's ring system is strongly forward scattering at visual wavelengths and consists of a narrow annulus of highest particle density, within which is a broader region in which the density is lower. On Io, changes are observed in eruptive activity, plume structure, and surface albedo patterns. Europa's surface retains little or no record of intense meteorite bombardment, but does reveal a complex and, as yet, little-understood system of overlapping bright and dark linear features. Ganymede is found to have at least one unit of heavily cratered terrain on a surface that otherwise suggests widespread tectonism. Except for two large ringed basins, Callisto's entire surface is heavily cratered. Copyright ?? 1979 AAAS.

  12. Voyager 1 planetary radio astronomy observations near Jupiter

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Pearce, J. B.; Riddle, A. C.; Alexander, J. K.; Desch, M. D.; Kaiser, M. L.; Thieman, J. R.; Carr, T. D.; Gulkis, S.; Boischot, A.

    1979-01-01

    Results from the first low-frequency radio receiver to be transported into the Jupiter magnetosphere are reported. Dramatic new information was obtained, both because Voyager was near or in Jupiter's radio emission sources and because it was outside the relatively dense solar wind plasma of the inner solar system. Extensive radio spectral arcs, from above 30 to about 1 MHz, occurred in patterns correlated with planetary longitude. A newly discovered kilometric wavelength radio source may relate to the plasma torus near Io's orbit. In situ wave resonances near closest approach define an electron density profile along the Voyager trajectory and form the basis for a map of the torus. Detailed studies are in progress and are outlined briefly.

  13. Voyager 1 Planetary Radio Astronomy Observations Near Jupiter

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Pearce, J. B.; Riddle, A. C.; Alexander, J. K.; Desch, M. D.; Kaiser, M. L.; Thieman, J. R.; Carr, T. B.; Gulkis, S.; Boischot, A.

    1979-01-01

    Results are reported from the first low frequency radio receiver to be transported into the Jupiter magnetosphere. Dramatic new information was obtained both because Voyager was near or in Jupiter's radio emission sources and also because it was outside the relatively dense solar wind plasma of the inner solar system. Extensive radio arcs, from above 30 MHz to about 1 MHz, occurred in patterns correlated with planetary longitude. A newly discovered kilometric wavelength radio source may relate to the plasma torus near Io's orbit. In situ wave resonances near closest approach define an electron density profile along the Voyager trajectory and form the basis for a map of the torus. Studies in progress are outlined briefly.

  14. Voyager 1 planetary radio astronomy observations near jupiter.

    PubMed

    Warwick, J W; Pearce, J B; Riddle, A C; Alexander, J K; Desch, M D; Kaiser, M L; Thieman, J R; Carr, T D; Gulkis, S; Boischot, A; Harvey, C C; Pedersen, B M

    1979-06-01

    We report results from the first low-frequency radio receiver to be transported into the Jupiter magnetosphere. We obtained dramatic new information, both because Voyager was near or in Jupiter's radio emission sources and also because it was outside the relatively dense solar wind plasma of the inner solar system. Extensive radio spectral arcs, from above 30 to about 1 megahertz, occurred in patterns correlated with planetary longitude. A newly discovered kilometric wavelength radio source may relate to the plasma torus near Io's orbit. In situ wave resonances near closest approach define an electron density profile along the Voyager trajectory and form the basis for a map of the torus. Detailed studies are in progress and are out-lined briefly.

  15. The Jovian nebula - A post-Voyager perspective

    NASA Technical Reports Server (NTRS)

    Trauger, J. T.

    1984-01-01

    Voyager 1 carried a diverse collection of magnetospheric probes through the inner Jovian magnetosphere in March 1979. The ensuing data analysis and theoretical investigation provided a comprehensive description of the Jovian nebula, a luminous torus populated with newly released heavy ions drawn from Io's surface. Recent refinements in earth-based imaging instrumentation are used to extend the Voyager in situ picture in temporal and spatial coverage. An analysis of S III and S II forbidden-line optical emissions observed during the Jovian apparitions of 1981 through 1983 reveals three distinct torus components. Regularities have been identified in the ion partitioning and ion densities in the hot outer and inner tori, sharply defined radial structure is found in the plasma near Io, and the relative permanence of the cool inner torus is inferred. An extended cloud of neutral material is required as a source of fresh ions in the nebula.

  16. Voyager detection of nonthermal radio emission from Saturn

    NASA Technical Reports Server (NTRS)

    Kaiser, M. L.; Desch, M. D.; Warwick, J. W.; Pearce, J. B.

    1980-01-01

    The detection of bursts of nonthermal radio noise from Saturn by the planetary radio astonomy experiment onboard the Voyager spacecraft is discussed. The emissions occur near 200 kHz with a peak flux density comparable to higher frequency Jovian emissions. The radiation is right-hand polarized and is most likely emitted in the extraordinary magnetoionic mode from Saturn's northern hemisphere. Modulation is apparent in the data which is consistent with a planetary rotation period of 10 hr 39.9 min.

  17. Voyager detection of nonthermal radio emission from saturn.

    PubMed

    Kaiser, M L; Desch, M D; Warwick, J W; Pearce, J B

    1980-09-12

    The planetary radio astronomy experiment on board the Voyager spacecraft has detected bursts of nonthermal radio noise from Saturn occurring near 200 kilohertz, with a peak flux density comparable to higher frequency Jovian emissions. The radiation is right-hand polarized and is most likely emitted in the extraordinary magnetoionic mode from Saturn's northern hemisphere. Modulation that is consistent with a planetary rotation period of 10 hours 39.9 minutes is apparent in the data.

  18. The Orbit of Pheobe from Earthbased and Voyager Observations

    NASA Technical Reports Server (NTRS)

    Jacobson, R. A.

    1996-01-01

    This article presents the results of a fit of a numerically integrated orbit for the Saturnian satellite Pheobe to Earthbased astrometric observations (from 1904 to 1996) and imaging data acquired by the Voyager 2 spacecraft during its encounter with Saturn. The primary results are the epoch state vector used in the integration and a set of mean elements which provide a geometrical representation of the orbit. We also assess the quality of the fit and the accuracy of the orbit.

  19. Mapping the Galilean satellites of Jupiter with Voyager data.

    USGS Publications Warehouse

    Batson, R.M.

    1980-01-01

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

  20. Review of the NASA Voyager spacecraft polycarbonate capacitor failure incident

    NASA Technical Reports Server (NTRS)

    Ott, F. M.; Yen, S. P. S.; Somoano, R. B.

    1985-01-01

    The premission failure of a Voyager spacecraft capacitor has prompted an investigation into the use of polycarbonate capacitors in high impedance circuits, during which capacitor failures were induced by thermal cycling together with extended periods at high temperature. Measurement of leakage path temperature coefficients indicates that there are two distinct leakage types whose mechanisms are complicated by movement within the capacitor during temperature changes. A novel system for pulse detection during capacitor burn-in and ramp testing has proven to be beneficial.

  1. Voyager-to-Galileo Changes, Io's Anti-Jove Hemisphere

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Shown here is a comparison of a Galileo color image (right) of Jupiter's moon Io, with a Voyager mosaic (left) reprojected to the same geometry as the Galileo image. The image on the right was obtained by the Galileo spacecraft's imaging camera on September 7th, 1996; the mosaic on the left was obtained by the Voyager spacecraft in 1979. Color is synthesized from green and violet filters only in both cases, as these are the only two filters that are reasonably similar between Voyager and Galileo. Many surface changes can be seen due to volcanic activity from 1979 to 1996. North is to the top of both frames. Galileo was about 487,000 kilometers (302,000 miles) from Io on September 7, 1996.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  2. Voyager and Pioneer Missions to the boundaries of the heliosphere

    NASA Technical Reports Server (NTRS)

    Pesses, M. E.; Jones, W. V.; Forman, M.

    1993-01-01

    The interaction of the solar wind with the interstellar medium is expected to result in a complex, probably dynamic outer heliospheric boundary region. In increasing distance from the sun the boundary region includes the solar wind termination shock, the heliopause, and perhaps a heliobowshock. The continuing missions of Voyager 1 and 2 and Pioneer 10 and 11 provide a unique opportunity to make in situ particle and field observations of the boundaries of the heliosphere and associated phenomena. Observations already made by these spacecraft suggest that the termination shock may be located 60-100 AU from the sun. Voyager 1 will reach 60 AU in 1995 and 100 AU in 2006. NASA's Space Physics Division is planning with the Voyager and Pioneer Projects to ensure timely and maximum scientific return from spacecraft encounters with the solar wind termination region. Initial emphasis is on being able to reliably determine when an encounter is imminent, so that spacecraft tracking and spacecraft and instrument configurations can be changed to encounter modes. It is anticipated that multiple encounters with heliospheric boundaries will occur due to motion of the boundaries in response to large variations in the solar wind pressure.

  3. Infrared observations of the jovian system from voyager 2.

    PubMed

    Hanel, R; Conrath, B; Flasar, M; Herath, L; Kunde, V; Lowman, P; Maguire, W; Pearl, J; Pirraglia, J; Samuelson, R; Gautier, D; Gierasch, P; Horn, L; Kumar, S; Ponnamperuma, C

    1979-11-23

    Infrared spectra obtainedfrom Voyager 2 have provided additional data on the Jovian system, complementing those obtained from Voyager 1. The abundance ratio of ethane to acetylene in Jupiter's atmosphere appears to be about three times larger in the polar regions than at lower latitudes. A decidedly hemispherical asymmetry exists, with somewhat higher ratios prevailing in northern latitudes. An overall increase in the abundance ratio by a factor of about 1.7 appears to have occurred between the Voyager 1 and 2 encounters. Global brightness temperature maps of Jupiter at 226 and 602 cm(-1) exhibit a large amount of local- and planetary-scale structure, as well as temporal variability. Although heterogeneous cloud structure and ammonia concentration in the lower troposphere may contribute to the appearance of the 226-cm(-1) map, the detail in the 602-cm(-1) maps probably represents the actual horizontal thermal structure near the tropopause and suggests that dynamical heating and cooling processes are important. Low-latitude surface temperatures on the Galilean satellites rangefrom approximately 80 K on the dark sides to 155 K at the subsolar point on Callisto. Below a thin insulating layer, the thermal inertia of Callisto is somewhat greater than that of Earth's moon. Upper limits on the infrared optical depth of the Jovian ring rangingfrom approximately 3 x 10(-4) at 250 cm(-1) to 3 x 10(-3) at 600 cm(-1) have been found.

  4. MORE EVIDENCE THAT VOYAGER 1 IS STILL IN THE HELIOSPHERE

    SciTech Connect

    Gloeckler, G.; Fisk, L. A.

    2015-06-20

    The investigators of the Voyager mission currently exploring the heliosheath have concluded and announced that Voyager 1 (V1) has crossed the heliopause and is now in the interstellar medium. This conclusion is based primarily on the plasma wave observations of Gurnett et al., which reveal a plasma electron density that resembles the density expected in the local interstellar medium. Fisk and Gloeckler have disputed the conclusion that V1 has crossed the heliopause, pointing out that to account for all the V1 observations, particularly the magnetic field direction together with the density, it is necessary to conclude that the higher densities observed by Gurnett et al. are due to compressed solar wind. In this Letter it is shown that the model of Fisk and Gloeckler for the nose region of the heliosheath can account in detail for the intensity and spectral shape of Energetic Neutral Hydrogen observed by the Interstellar Boundary Explorer (IBEX) in the directions of V1 and Voyager 2 (V2). A key feature of the Fisk and Gloeckler model is the existence of a region in the heliosheath where the solar wind is compressed and heated, followed by a region where the solar wind is compressed but cold. The region of cold compressed solar wind provides a unique explanation for the low-energy IBEX observations, and since this is the region where V1 must now reside, the low-energy IBEX observations provide strong evidence that V1 is still in the heliosphere.

  5. Abundances of Jupiter's Trace Hydrocarbons from Voyager and Cassini

    NASA Technical Reports Server (NTRS)

    Nixon, C. A.; Achterberg, R. K.; Romani, P. N.; Allen, M.; Zhang, X.; Teanby, N. A.; Irwin, P. G. J.; Flasar, F. M.

    2010-01-01

    The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, to retrieve the vertical and meridional profiles of temperature, and the abundances of the two minor hydrocarbons, acetylene (C2H2) and ethane (C2H6). The spatial variation of these gases is controlled by both chemistry and dynamics, and therefore their observed distribution gives us an insight into both processes, We find that the two gases paint quite different pictures of seasonal change. Whilst the 2-D cross-section of C2H6 abundance is slightly increased and more symmetric in 2000 (northern summer solstice) compared to 1979 (northern fall equinox), the major trend of equator to pole increase remains. For C2H2 on tile other hand, the Voyager epoch exhibits almost no latitudinal variation, whilst the Cassini era shows a marked decrease polewards in both hemispheres. At the present time, these experimental findings are in advance of interpretation, as there are no published models of 2-D Jovian seasonal chemical variation available for comparison.

  6. Planetary radio astronomy observations from Voyager-2 near Saturn

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Evans, D. R.; Romig, J. H.; Alexander, J. K.; Desch, M. D.; Kaiser, M. L.; Aubier, M.; Leblanc, Y.; Lecacheux, A.; Pedersen, B. M.

    1981-01-01

    Voyager-2 planetry radio astronomy measurements obtained near Saturn are discussed. They indicate that Saturnian kilometric radiation is emitted by a strong, dayside source at auroral latitudes in the northern hemisphere and by a weaker (by more than an order of magnitude) source at complementary latitudes in the southern hemisphere. These emissions are variable both due to Saturn's rotation and, on longer time scales, probably due to influences of the solar wind and the satellite Dione. The Saturn electrostatic discharge bursts first discovered by Voyager-1 and attributed to emissions from the B-ring were again observed with the same broadband spectral properties and a 10(h)11(m) + or - 5(m) episodic recurrence period but with an occurrence frequency of only of about 30 percent of that detected with Voyager-1. During the crossing of the ring plane at a distance of 2.88 R sub S, an intense noise event is interpreted to be consequence of the impact/vaporization/ionization of charged micron-size G-ring particles distributed over a total vertical thickness of about 1500 km.

  7. Planetary radio astronomy observations from Voyager 2 near Saturn

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Evans, D. R.; Romig, J. H.; Alexander, J. K.; Desch, M. D.; Kaiser, M. L.; Aubier, M.; Leblanc, Y.; Lecacheux, A.; Pedersen, B. M.

    1982-01-01

    Planetary radio astronomy measurements obtained by Voyager 2 near Saturn have added further evidence that Saturnian kilometric radiation is emitted by a strong dayside source at auroral latitudes in the northern hemisphere and by a weaker source at complementary latitudes in the southern hemisphere. These emissions are variable because of Saturn's rotation and, on longer time scales, probably because of influences of the solar wind and Dione. The electrostatic discharge bursts first discovered by Voyager 1 and attributed to emissions from the B ring were again observed with the same broadband spectral properties and an episodic recurrence period of about 10 hours, but their occurrence frequency was only about 30 percent of that detected by Voyager 1. While crossing the ring plane at a distance of 2.88 Saturn radii, the spacecraft detected an intense noise event extending to above 1 megahertz and lasting about 150 seconds. The event is interpreted to be a consequence of the impact, vaporization, and ionization of charged, micrometer-size G ring particles distributed over a vertical thickness of about 1500 kilometers.

  8. Planetary radio astronomy observations from voyager 2 near saturn.

    PubMed

    Warwick, J W; Evans, D R; Romig, J H; Alexander, J K; Desch, M D; Kaiser, M L; Aubier, M; Leblanc, Y; Lecacheux, A; Pedersen, B M

    1982-01-29

    Planetary radio astronomy measurements obtained by Voyager 2 near Saturn have added further evidence that Saturnian kilometric radiation is emitted by a strong dayside source at auroral latitudes in the northern hemisphere and by a weaker source at complementary latitudes in the southern hemisphere. These emissions are variable because of Saturn's rotation and, on longer time scales, probably because of influences of the solar wind and Dione. The electrostatic discharge bursts first discovered by Voyager 1 and attributed to emissions from the B ring were again observed with the same broadband spectral properties and an episodic recurrence period of about 10 hours, but their occurrence frequency was only about 30 percent of that detected by Voyager 1. While crossing the ring plane at a distance of 2.88 Saturn radii, the spacecraft detected an intense noise event extending to above 1 megahertz and lasting about 150 seconds. The event is interpreted to be a consequence of the impact, vaporization, and ionization of charged, micrometer-size G ring particles distributed over a vertical thickness of about 1500 kilometers.

  9. Extreme and far ultraviolet astronomy from Voyagers 1 and 2

    NASA Technical Reports Server (NTRS)

    Holberg, J. B.

    1990-01-01

    The instrumental characteristics, observational capabilities and scientific results of the Voyager 1 and 2 ultraviolet spectrometers are reviewed. These instruments provide current and ongoing access to low resolution spectra for a wide variety of astronomical sources in the 500 to 1700 A band. Observations of the brightest OB stars and hot subluminous stars as faint as V = 15 mag, are possible. In the EUV, at wavelengths shortward of 900 A, several new sources have been detected and a host of potential sources ruled out. In the far UV, particularly at wavelengths between 900 and 1200 A, Voyager is capable of observing a wide range of stellar and non-stellar sources. Such observations can often provide a valuable complement to IUE and other data sets at longer wavelengths. The Voyager spectrometers have proved remarkably stable photon counting instruments, capable of extremely long integration times. The long integration times, relatively large field of view, and location in the outer solar system also provide an ideal platform for observations of sources of faint diffuse emission, such as nebulae and the general sky background.

  10. Voyager electronic parts radiation program. Volume 2: Test requirements and procedures

    NASA Technical Reports Server (NTRS)

    Stanley, A. G.; Martin, K. E.; Price, W. E.

    1978-01-01

    Documents are presented outlining the conditions and requirements of the test program. The Appendixes are as follows: appendix A -- Electron Simulation Radiation Test Specification for Voyager Electronic Parts and Devices, appendix B -- Electronic Piece-Part Testing Program for Voyager, appendix C -- Test Procedure for Radiation Screening of Voyager Piece Parts, appendix D -- Boeing In Situ Test Fixture, and appendix E -- Irradiate - Anneal (IRAN) Screening Documents.

  11. Exploring the brain, looking for thoughts: on Asimov's second Fantastic Voyage.

    PubMed

    Cassou-Noguès, Pierre

    2011-01-01

    The aim of this paper is to investigate various concerns which appear in Isaac Asimov's Fantastic Voyage II: Destination Brain. I will disregard his first voyage inside a human body in Fantastic Voyage I, which the author disavows as not being his own work. In contrast, the second voyage is intricate, suggesting problems drawn from a variety of sources. In a nutshell, Asimov's explorers enter the body of a comatose man in order to read his thoughts. The story can be related both to philosophical thought-experiments, such as those of Gottfried Wilhelm Leibniz and of Herbert Feigl, as well as to personal anxieties peculiar to Asimov.

  12. Energetic Particle Anisotropies at Voyager 1 in the Local Interstellar Medium and at Voyager 2 in the Heliosheath

    NASA Astrophysics Data System (ADS)

    Decker, R. B.; Krimigis, S. M.; Hill, M. E.; Roelof, E. C.

    2015-12-01

    We describe angular variations of energetic ion and electron intensities measured by the Low Energy Charged Particle instruments on Voyager 1 in the very local interstellar medium, and for context, at Voyager 2 in the heliosheath. We emphasize measurements made in 2014-2015. At Voyager 1, now at 132 AU and 11 AU beyond the heliopause, intensities of low-energy ions and electrons and of anomalous cosmic rays remain at background levels. Galactic cosmic ray ions continue to show small departures from isotropy, with broad (0.3-0.5 year) episodes of intensity depletions of ions gyrating nearly perpendicular to the magnetic field. Percentage intensity decreases during these depletions, relative to intensities of cosmic rays propagating along the field, peak at -7% in 2013.35, -3% in 2014.50, and at least -4% in 2015.60 (when the most recent data were examined). Two episodes in March-April 2013 and April-May 2014 when cosmic ray ion intensities showed small increases lasting 10-20 days indicate small energy boosts, produced possibly by magnetic disturbances from solar activity entering the interstellar medium [Gurnett et al., Ap. J. 2015]. During these two periods intensities of cosmic rays with pitch angles nearer 90 degrees were increased more than those with pitch angles nearer 0 and 180 degrees. At Voyager 2, now 24 AU beyond the termination shock, intensities of ions >30 keV and electrons >20 keV continue to recover in a step-like fashion from minima reached in early 2013. We reported previously that during the rapid initial recovery from these minima as particle intensities rose at Voyager 2, angular data for ions 30 keV to 30 MeV (i.e., including anomalous cosmic rays) showed strong and long lasting (about 4 months) net streaming away from the heliospheric nose toward the flank. A similar streaming episode lasting about 2 months occurred in early 2015, again during a period when intensities were rapidly increasing.

  13. Comparison of modal test methods on the Voyager payload

    NASA Technical Reports Server (NTRS)

    Hanks, B. R.; Miserentino, R.; Ibrahim, S. R.; Lee, S. H.; Wada, B. K.

    1978-01-01

    A comparison of the performance of modern modal data analysis methods on test data from the Voyager Jupiter/Saturn payload is presented. Four different test/data-analysis combinations are compared - multiple-point sine excitation tests, single-point random-excitation tests using two different techniques of manipulating Fourier transform data, and a time-domain method for analyzing random data. Results indicate that all four methods can give comparable results. Of the four, the time-domain approach detects more modes in the test data and, at the same time, shows the greatest promise for reducing the time and cost of modal testing.

  14. Jupiter plasma wave observations: an initial voyager 1 overview.

    PubMed

    Scarf, F L; Gurnett, D A; Kurth, W S

    1979-06-01

    The Voyager I plasma wave instrument detected low-frequency radio emissions, ion acoustic waves, and electron plasma oscillations for a period of months before encountering Jupiter's bow shock. In the outer magnetosphere, measurements of trapped radio waves were used to derive an electron density profile. Near and within the Io plasma torus the instrument detected high-frequency electrostatic waves, strong whistler mode turbulence, and discrete whistlers, apparently associated with lightning. Some strong emissions in the tail region and some impulsive signals have not yet been positively identified.

  15. Microwave communications from outer planets - The Voyager Project

    NASA Technical Reports Server (NTRS)

    Brejcha, A. G.

    1980-01-01

    The paper summarizes the Voyager Project, the mission objectives, and the spacecraft communications system required to meet the mission objectives. The primary emphasis of the mission is on comparative studies of the Jupiter and Saturn systems in the areas of: (1) the environment, atmosphere and body characteristics of the planets, and one or more of the satellites, (2) the nature of the recently discovered Jovian ring and the rings of Saturn, and (3) the interplanetary medium at increasing distances from the sun. The complexities and problems, such as power consumption, weight, and antenna pointing constraints are presented, along with a detailed description of the radio frequency and S/X-band antenna subsystems.

  16. The Jupiter system through the eyes of Voyager 1

    USGS Publications Warehouse

    Smith, B.A.; Soderblom, L.A.; Johnson, T.V.; Ingersoll, A.P.; Collins, S.A.; Shoemaker, E.M.; Hunt, G.E.; Masursky, H.; Carr, M.H.; Davies, M.E.; Cook, A.F.; Boyce, J.; Danielson, G.E.; Owen, editors, Timothy W.; Sagan, C.; Beebe, R.F.; Veverka, J.; Strom, R.G.; McCauley, J.F.; Morrison, D.; Briggs, G.A.; Suomi, V.E.

    1979-01-01

    The cameras aboard Voyager I have provided a closeup view of the Jupiter system, revealing heretofore unknown characteristics and phenomena associated with the planet's atmosphere and the surfaces of its five major satellites. On Jupiter itself, atmospheric motions-the interaction of cloud systems-display complex vorticity. On its dark side, lightning and auroras are observed. A ring was discovered surrounding Jupiter. The satellite surfaces display dramatic differences including extensive active volcanismn on Io, complex tectonism on Ganymnede and possibly Europa, and flattened remnants of enormous impact features on Callisto. Copyright ?? 1979 AAAS.

  17. Interagency telemetry arraying for Voyager-Neptune encounter

    NASA Technical Reports Server (NTRS)

    Brown, D. W.; Brundage, W. D.; Ulvestad, J. S.; Kent, S. S.; Bartos, K. P.

    1990-01-01

    The reception capability of the Deep Space Network (DSN) has been improved over the years by increasing both the size and number of antennas at each complex to meet spacecraft-support requirements. However, even more aperture was required for the final planetary encounters of the Voyager 2 spacecraft. This need was met by arraying one radio astronomy observatory with the DSN complex in the United States and another with the complex in Australia. Following a review of augmentation for the Uranus encounter, both the preparation at the National Radio Astronomy (NRAO) Very Large Array (VLA) and the Neptune encounter results for the Parkes-Canberra and VLA-Goldstone arrays are presented.

  18. Radio propagation experiments in the outer solar system with Voyager

    NASA Technical Reports Server (NTRS)

    Tyler, G. Leonard

    1987-01-01

    The outer solar system's planetary atmospheres, ionospheres, rings, and magnetic fields are under study in light of microwave telecommunications from the two Voyager spacecraft. The use of the hydrogen maser frequency standards on the ground, in conjunction with thermally controlled quartz oscillators aboard the spacecraft, ensures long coherence intervals and allows the application of novel signal processing methods. On this basis, studies of atmospheric structure and scintillation parameters, planetary ring structure, and magnetic control of small ionospheric irregularities have been undertaken; information concerning planetary evolution, composition, and dynamics is thereby obtained.

  19. Far-ultraviolet extinction determined from Voyager data

    NASA Technical Reports Server (NTRS)

    Snow, Theodore P.; Allen, M. M.; Polidan, R. S.

    1990-01-01

    Data from the Voyager UV spectrometers are used to derive FUV extinction curves for 19 stars, using the pair-comparison method after the removal of the effects of line absorption due to H I and H2. It is shown that the FUV extinction rise continues to the limit of the data at about 925 A, supporting the theoretical prediction by Longo et al. (1989) that the FUV extinction continues to rise toward short wavelengths all the way to the Lyman limit at 912 A.

  20. Preliminary science results of Voyager 1 Saturn encounter

    NASA Technical Reports Server (NTRS)

    Bane, D.

    1981-01-01

    Preliminary science results of the Voyager 1 encounter of the planet Saturn are reported. On August 22, 1980, the spacecraft was 109 million km (68 million mi) from Saturn. Closest approach to Saturn took place on November 12, at 3:46 p.m. (PDT), when the spacecraft passed 126,000 km (78,000 mi) from the cloud tops. Measurements of the atmosphere, wind speed, radiation, six surrounding rings, and the planet's old and newly found satellites were recorded. The encounter ended December 15, 1980. The spacecraft took more than 17,500 photographs of Saturn and its satellites.

  1. Planetary radio astronomy observations from Voyager 1 near Saturn

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.; Pearce, J. B.; Evans, D. R.; Carr, T. D.; Schauble, J. J.; Alexander, J. K.; Kaiser, M. L.; Desch, M. D.; Pedersen, M.; Lecacheux, A.

    1981-01-01

    The Voyager 1 planetary radio astronomy experiment detected two distinct kinds of radio emissions from Saturn. The first, Saturn kilometric radiation, is strongly polarized, bursty, tightly correlated with Saturn's rotation, and exhibits complex dynamic spectral features somewhat reminiscent of those in Jupiter's radio emission. It appears in radio frequencies below about 1.2 megahertz. The second kind of radio emission, Saturn electrostatic discharge, is unpolarized, extremely impulsive, loosely correlated with Saturn's rotation, and very broadband, appearing throughout the observing range of the experiment (20.4 kilohertz to 40.2 megahertz). Its sources appear to lie in the planetary rings.

  2. Planetary radio astronomy observations during the Voyager 1 Titan flyby

    NASA Technical Reports Server (NTRS)

    Daigne, G.; Pedersen, B. M.; Kaiser, M. L.; Desch, M. D.

    1982-01-01

    During the Voyager 1 Titan flyby, unusual radio emissions were observed by the planetary radio astronomy experiment in the 20- to 97-kHz frequency range. It is shown that Titan itself is not the source of the observed radio emission. The emission features are attributed to modification of the normal Saturn kilometric radiation by propagation effects in enhanced density structures within the Titan wake. Furthermore, spiky emissions observed in the magnetic wake of Titan are interpreted in terms of local electrostatic instabilities at the electron plasma frequency. From these measurements a range of electron densities in the wake region is derived, and the consistency of the results is discussed.

  3. DETAIL OF PLAQUE COMMEMORATING THE JULY/ AUGUST 1958 VOYAGE OF ...

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

    DETAIL OF PLAQUE COMMEMORATING THE JULY/ AUGUST 1958 VOYAGE OF THE USS NAUTILUS (SSN-571) TO THE NORTH POLE. NOTE: THIS PLAQUE IS NOT LOCATED AT WHARFS S13-S19; IT IS AT THE SUBMARINE MEMORIAL PARK, ABOUT 1,000' SOUTH OF THE WHARFS. THE LOCATION AND ORIENTATION OF THIS PHOTO IS NOT SHOWN ON THE PHOTO KEY MAP - U.S. Naval Base, Pearl Harbor, Additional Piers and Quay Walls, S13 to S19, Northeast end of Magazine Loch, Pearl City, Honolulu County, HI

  4. Planetary radio astronomy observations from voyager 1 near saturn.

    PubMed

    Warwick, J W; Pearce, J B; Evans, D R; Carr, T D; Schauble, J J; Alexander, J K; Kaiser, M L; Desch, M D; Pedersen, M; Lecacheux, A; Daigne, G; Boischot, A; Barrow, C H

    1981-04-10

    The Voyager 1 planetary radio astronomy experiment detected two distinct kinds of radio emissions from Saturn. The first, Saturn kilometric radiation, is strongly polarized, bursty, tightly correlated with Saturn's rotation, and exhibits complex dynamic spectral features somewhat reminiscent of those in Jupiter's radio emission. It appears in radio frequencies below about 1.2 megahertz. The second kind of radio emission, Saturn electrostatic discharge, is unpolarized, extremely impulsive, loosely correlated with Saturn's rotation, and very broadband, appearing throughout the observing range of the experiment (20.4 kilohertz to 40.2 megahertz). Its sources appear to lie in the planetary rings.

  5. The jupiter system through the eyes of voyager 1.

    PubMed

    Smith, B A; Soderblom, L A; Johnson, T V; Ingersoll, A P; Collins, S A; Shoemaker, E M; Hunt, G E; Masursky, H; Carr, M H; Davies, M E; Cook, A F; Boyce, J; Danielson, G E; Owen, T; Sagan, C; Beebe, R F; Veverka, J; Strom, R G; McCauley, J F; Morrison, D; Briggs, G A; Suomi, V E

    1979-06-01

    The cameras aboard Voyager 1 have provided a closeup view of the Jupiter system, revealing heretofore unknown characteristics and phenomena associated with the planet's atmosphere and the surfaces of its five major satellites. On Jupiter itself, atmospheric motions-the interaction of cloud systems-display complex vorticity. On its dark side, lightning and auroras are observed. A ring was discovered surrounding Jupiter. The satellite surfaces display dramatic differences including extensive active volcanismn on Io, complex tectonism on Ganymnede and possibly Europa, and flattened remnants of enormous impact features on Callisto. PMID:17800430

  6. Voyager image processing at the Image Processing Laboratory

    NASA Technical Reports Server (NTRS)

    Jepsen, P. L.; Mosher, J. A.; Yagi, G. M.; Avis, C. C.; Lorre, J. J.; Garneau, G. W.

    1980-01-01

    This paper discusses new digital processing techniques as applied to the Voyager Imaging Subsystem and devised to explore atmospheric dynamics, spectral variations, and the morphology of Jupiter, Saturn and their satellites. Radiometric and geometric decalibration processes, the modulation transfer function, and processes to determine and remove photometric properties of the atmosphere and surface of Jupiter and its satellites are examined. It is exhibited that selected images can be processed into 'approach at constant longitude' time lapse movies which are useful in observing atmospheric changes of Jupiter. Photographs are included to illustrate various image processing techniques.

  7. Voyager photometry of Triton - Haze and surface photometric properties

    NASA Technical Reports Server (NTRS)

    Hillier, J.; Helfenstein, P.; Verbiscer, A.; Veverka, J.

    1991-01-01

    The Voyager whole-disk observations of Triton at 0.41, 0.48, and 0.56 micron filter wavelengths are analyzed using a model which combines an improved version of Hapke's photometric equation with a thin atmospheric haze layer in the appropriate spherical geometry. The model is shown to describe accurately the phase curves over a range of phase angles and to agree with disk-resolved brightness scans along the photometric equator and mirror meridian. According to the model, the photometric parameters of Triton's regolith are reasonably typical of icy satellites, except for the extremely high (close to unity) single-scattering albedo.

  8. Post Voyager comparisons of the interiors of Uranus and Neptune

    NASA Technical Reports Server (NTRS)

    Podolak, M.; Reynolds, R. T.; Young, R.

    1990-01-01

    The recent Voyager flyby of Uranus and Neptune has provided refined values for the gravitational moments and rotation periods of those planets. Using these new parameters, models of the interiors of these planets show that their density distributions are very similar. This lends support to the conjecture that their compositions are similar as well. The models are indeed consistent with such a conjecture. The difference in the internal heat sources of these two planets may be due to the fact that heat transport from the interior of Uranus is inhibited by a statically stable interior.

  9. Plasma observations near Saturn - Initial results from Voyager 1

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Belcher, J. W.; Lazarus, A. J.; Olbert, S.; Sullivan, J. D.; Bagenal, F.; Gazis, P. R.; Hartle, R. E.; Ogilvie, K. W.; Scudder, J. D.

    1981-01-01

    The Voyager 1 encounter with Saturn and its satellites yielded extensive measurements of magnetospheric low-energy plasma electrons and positive ions, both heavy and light, probably of hydrogen and nitrogen or oxygen. At radial distances between 15 and 7 Saturn radii on the inbound trajectory, the plasma appears to corotate with a velocity within 20% of that theoretically expected for rigid corotation. The Titan data, taken while the moon was inside the Saturn magnetosphere, shows a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan.

  10. The jupiter system through the eyes of voyager 1.

    PubMed

    Smith, B A; Soderblom, L A; Johnson, T V; Ingersoll, A P; Collins, S A; Shoemaker, E M; Hunt, G E; Masursky, H; Carr, M H; Davies, M E; Cook, A F; Boyce, J; Danielson, G E; Owen, T; Sagan, C; Beebe, R F; Veverka, J; Strom, R G; McCauley, J F; Morrison, D; Briggs, G A; Suomi, V E

    1979-06-01

    The cameras aboard Voyager 1 have provided a closeup view of the Jupiter system, revealing heretofore unknown characteristics and phenomena associated with the planet's atmosphere and the surfaces of its five major satellites. On Jupiter itself, atmospheric motions-the interaction of cloud systems-display complex vorticity. On its dark side, lightning and auroras are observed. A ring was discovered surrounding Jupiter. The satellite surfaces display dramatic differences including extensive active volcanismn on Io, complex tectonism on Ganymnede and possibly Europa, and flattened remnants of enormous impact features on Callisto.

  11. The Columbian Voyages, the Columbian Exchange, and Their Historians. Essays on Global and Comparative History.

    ERIC Educational Resources Information Center

    Crosby, Alfred W.

    The 500th anniversary of the Columbian discovery of America is upon us, and with it the obligation to assess existing interpretations of the significance of the voyage and establishment of permanent links between the Old and New Worlds. The traditional, or bardic, version of the Columbian voyages and their consequences was the product of narrative…

  12. 46 CFR 188.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... mandate, whose international relations are the responsibility of a contracting SOLAS 74 government, or... 46 Shipping 7 2011-10-01 2011-10-01 false Application to vessels on an international voyage. 188... international voyage. (a) Except as provided in paragraphs (b), (c), and (d) of this section, the regulations...

  13. 46 CFR 70.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., whose international relations are the responsibility of a contracting SOLAS 74 government, or which is... 46 Shipping 3 2011-10-01 2011-10-01 false Application to vessels on an international voyage. 70.05... VESSELS GENERAL PROVISIONS Application § 70.05-10 Application to vessels on an international voyage....

  14. 46 CFR 14.201 - Voyages upon which shipping articles are required.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Voyages upon which shipping articles are required. 14.201 Section 14.201 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS Shipment of Merchant Mariners § 14.201 Voyages upon which shipping articles are required....

  15. 46 CFR 167.65-65 - Notice and reporting of casualty and voyage records.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Notice and reporting of casualty and voyage records. 167... SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Special Operating Requirements § 167.65-65 Notice and reporting of casualty and voyage records. The requirements for providing notice and reporting of marine casualties...

  16. 33 CFR 169.210 - Where during its international voyage must a ship transmit position reports?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... identified in § 169.205. (a) Flag State relationship. A U.S. flag ship engaged on an international voyage... intention to enter a U.S. port or place under requirements in 33 CFR part 160, subpart C. (c) Coastal State relationship. A foreign flag ship engaged on an international voyage must transmit position reports when...

  17. 46 CFR 188.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Application to vessels on an international voyage. 188... international voyage. (a) Except as provided in paragraphs (b), (c), and (d) of this section, the regulations in this subchapter that apply to a vessel on an “international voyage” apply to a vessel that— (1)...

  18. 46 CFR 70.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Application to vessels on an international voyage. 70.05... VESSELS GENERAL PROVISIONS Application § 70.05-10 Application to vessels on an international voyage. (a... that apply to a vessel on an “international voyage” apply to a vessel that— (1) Is...

  19. 33 CFR 104.297 - Additional requirements-vessels on international voyages.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Security Certificate (ISSC) as provided in 46 CFR § 2.01-25 is obtained for the vessel. This certificate... on international voyages. 104.297 Section 104.297 Navigation and Navigable Waters COAST GUARD... § 104.297 Additional requirements—vessels on international voyages. (a) An owner or operator of a...

  20. 46 CFR 14.201 - Voyages upon which shipping articles are required.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Voyages upon which shipping articles are required. 14.201 Section 14.201 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS Shipment of Merchant Mariners § 14.201 Voyages upon which shipping articles are required....

  1. 46 CFR 14.201 - Voyages upon which shipping articles are required.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Voyages upon which shipping articles are required. 14.201 Section 14.201 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY MERCHANT MARINE OFFICERS AND SEAMEN SHIPMENT AND DISCHARGE OF MERCHANT MARINERS Shipment of Merchant Mariners § 14.201 Voyages upon which shipping articles are required....

  2. Voyager 2's encounter with Neptune answered many questions about the 'blue' planet

    SciTech Connect

    Tsurutani, B.T. )

    1990-02-01

    Voyager 2 observations of Neptune from August 1989 are examined. Voyager 2 discovered 6 new moons around Neptune and collected information on the shape and composition of Neptune's rings. The spots and clouds detected in the planet's atmosphere are described. Consideration is given to Neptune's magnetic field and auroras.

  3. 46 CFR 90.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Application to vessels on an international voyage. 90.05-10 Section 90.05-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS GENERAL PROVISIONS Application § 90.05-10 Application to vessels on an international voyage. (a) Except for yachts and...

  4. Magnetic field measurements at Jupiter by Voyagers 1 and 2: Daily plots of 48 second averages

    NASA Technical Reports Server (NTRS)

    Lepping, R. P.; Silverstein, M. J.; Ness, N. F.

    1981-01-01

    A series of 24 hour summary plots of the magnetic field, in 48-s average form, measured in the vicinity of Jupiter by the magnetometers onboard Voyagers 1 and 2 are presented. The Voyager 1 data cover the period from 27 February 1979 (day = 58) to 23 March (day = 82) inclusive, and the Voyager 2 data cover the period from 2 July 1979 (day = 183) to 14 August (day = 226) inclusive. Closest approach to the planet occurred on days 64 (AT 1205 UT) and 190 (AT 2230 UT) for Voyagers 1 and 2, respectively. Also included are: a description of the characteristics of the magnetometers, a brief description of the near-planet trajectories of the two spacecraft, a listing of the bow shock and magnetopause crossing times, and a bibliography containing Voyager-Jupiter related papers and reports.

  5. A summary of whistlers observed by Voyager 1 at Jupiter

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Strayer, B. D.; Gurnett, D. A.; Scarf, F. L.

    1985-01-01

    We summarize the Voyager 1 observations of whistlers at Jupiter in order to provide a basis for further analyses of the density profile of the Io plasma torus as well as to support studies of atmospheric lightning at Jupiter. All the whistlers detected by Voyager 1 fell into three general regions in the torus at radial distances ranging beteen 5 and 6 R sub J. An analysis of the broadband wave amplitudes measured by the Voyayer 1 plasma wave instrument and estimates of the peak whistler amplitudes imply the grouping of whistlers was due to variations in the sensitivity of the receiver to whistlers and not to variations in the source or propagation paths of the whistlers. The whistler dispersions are presented in statistical form for each of the three groups of events and analyzed in view of the structure of the Io plasma torus as determined by plasma probe measurements. The results of these analyses give source locations for the whistlers at the foot of the magnetic field lines threading the torus in both hemispheres and over a range of longitudes.

  6. Vision and Voyages: Lessons Learned from the Planetary Decadal Survey

    NASA Astrophysics Data System (ADS)

    Squyres, S. W.

    2015-12-01

    The most recent planetary decadal survey, entitled Vision and Voyages for Planetary Science in the Decade 2013-2022, provided a detailed set of priorities for solar system exploration. Those priorities drew on broad input from the U.S. and international planetary science community. Using white papers, town hall meetings, and open meetings of the decadal committees, community views were solicited and a consensus began to emerge. The final report summarized that consensus. Like many past decadal reports, the centerpiece of Vision and Voyages was a set of priorities for future space flight projects. Two things distinguished this report from some previous decadals. First, conservative and independent cost estimates were obtained for all of the projects that were considered. These independent cost estimates, rather than estimates generated by project advocates, were used to judge each project's expected science return per dollar. Second, rather than simply accepting NASA's ten-year projection of expected funding for planetary exploration, decision rules were provided to guide program adjustments if actual funding did not follow projections. To date, NASA has closely followed decadal recommendations. In particular, the two highest priority "flagship" missions, a Mars rover to collect samples for return to Earth and a mission to investigate a possible ocean on Europa, are both underway. The talk will describe the planetary decadal process in detail, and provide a more comprehensive assessment of NASA's response to it.

  7. Plasma wave observations near jupiter: initial results from voyager 2.

    PubMed

    Gurnett, D A; Kurth, W S; Scarf, F L

    1979-11-23

    This report provides an initial survey of results from the plasma wave instrument on the Voyager 2 spacecraft, which flew by Jupiter on 9 July 1979. Measurements made during the approach to the planet show that low-frequency radio emissions from Jupiter have a strong latitudinal dependence, with a sharply defined shadow zone near the equatorial plane. At the magnetopause a new type of broadband electric field turbulence was detected, and strong electrostatic emissions near the upper hybrid resonance frequency were discovered near the low-frequency cutoff of the continuum radiation. Strong whistler-mode turbulence was again detected in the inner magnetosphere, although in this case extending out to substantially larger radial distances than for Voyager 1. In the predawn tail region, continuum radiation was observed extending down to extremely low frequencies, approximately 30 hertz, an indication that the spacecraft was entering a region of very low density, approximately 1.0 x 10(-5) per cubic centimeter, possibly similar to the lobes of Earth's magnetotail.

  8. Magnetic field studies at jupiter by voyager 2: preliminary results.

    PubMed

    Ness, N F; Acuna, M H; Lepping, R P; Burlaga, L F; Behannon, K W; Neubauer, F M

    1979-11-23

    Data from the Goddard Space Flight Center magnetometers on Voyager 2 have yielded on inbound trajectory observations of multiple crossings of the bow shock and magnetosphere near the Jupiter-sun line at radial distances of 99 to 66 Jupiter radii (RJ) and 72 to 62 RJ, respectively. While outbound at a local hour angle of 0300, these distances increase appreciably so that at the time of writing only the magnetopause has been observed between 160 and 185 RJ. These results and the magnetic field geometry confirm the earlier conclusion from Voyager I studies that Jupiter has an enormous magnetic tail, approximately 300 to 400 RJ in diameter, trailing behind the planet with respect to the supersonic flow of the solar wind. Addi- tional observations of the distortion of the inner magnetosphere by a concentrated plasma show a spatial merging of the equatorial magnetodisk current with the cur- rent sheet in the magnetic tail. The spacecraft passed within 62,000 kilometers of Ganymede (radius = 2,635 kilometers) and observed characteristic fluctuations in- terpreted tentatively as being due to disturbances arising from the interaction of the Jovian magnetosphere with Ganymede.

  9. Magnetic field studies by voyager 1: preliminary results at saturn.

    PubMed

    Ness, N F; Acuña, M H; Lepping, R P; Connerney, J E; Behannon, K W; Burlaga, L F; Neubauer, F M

    1981-04-10

    Magnetic field studies by Voyager 1 have confirmed and refined certain general features of the Saturnian magnetosphere and planetary magnetic field established by Pioneer 11 in 1979. The main field of Saturn is well represented by a dipole of moment 0.21 +/- 0.005 gauss-R(s)(3) (where 1 Saturn radius, R(s), is 60,330 kilometers), tilted 0.7 degrees +/- 0.35 degrees from the rotation axis and located within 0.02 R(s) of the center of the planet. The radius of the magnetopause at the subsolar point was observed to be 23 R(s) on the average, rather than 17 R(s). Voyager 1 discovered a magnetic tail of Saturn with a diameter of approximately 80 R(s). This tail extends away from the Sun and is similar to type II comet tails and the terrestrial and Jovian magnetic tails. Data from the very close flyby at Titan (located within the Saturnian magnetosphere) at a local time of 1330, showed an absence of any substantial intrinsic satellite magnetic field. However, the results did indicate a very well developed, induced magnetosphere with a bipolar magnetic tail. The upper limit to any possible internal satellite magnetic moment is 5 x 10(21) gauss-cubic centimeter, equivalent to a 30-nanotesla equatorial surface field.

  10. MULTIFRACTAL STRUCTURES DETECTED BY VOYAGER 1 AT THE HELIOSPHERIC BOUNDARIES

    SciTech Connect

    Macek, W. M.; Burlaga, L. F. E-mail: anna.wawrzaszek@cbk.waw.pl

    2014-10-01

    To better understand the dynamics of turbulent systems, we have proposed a phenomenological model based on a generalized Cantor set with two rescaling and one weight parameters. In this Letter, using recent Voyager 1 magnetic field data, we extend our two-scale multifractal analysis further in the heliosheath beyond the heliospheric termination shock, and even now near the heliopause, when entering the interstellar medium for the first time in human history. We have identified the scaling inertial region for magnetized heliospheric plasma between the termination shock and the heliopause. We also show that the degree of multifractality decreases with the heliocentric distance and is still modulated by the phases of the solar cycle in the entire heliosphere including the heliosheath. Moreover, we observe the change of scaling toward a nonintermittent (nonmultifractal) behavior in the nearby interstellar medium, just beyond the heliopause. We argue that this loss of multifractal behavior could be a signature of the expected crossing of the heliopause by Voyager 2 in the near future. The results obtained demonstrate that our phenomenological multifractal model exhibits some properties of intermittent turbulence in the solar system plasmas, and we hope that it could shed light on universal characteristics of turbulence.

  11. Encounter with Saturn: Voyager 1 imaging science results

    USGS Publications Warehouse

    Smith, B.A.; Soderblom, L.; Beebe, R.; Boyce, J.; Briggs, G.; Bunker, A.; Collins, S.A.; Hansen, C.J.; Johnson, T.V.; Mitchell, J.L.; Terrile, R.J.; Carr, M.; Cook, A.F.; Cuzzi, J.; Pollack, James B.; Edward, Danielson G.; Ingersoll, A.; Davies, M.E.; Hunt, G.E.; Masursky, H.; Shoemaker, E.; Morrison, D.; Owen, editors, Timothy W.; Sagan, C.; Veverka, J.; Strom, R.; Suomi, V.E.

    1981-01-01

    As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of "ringlets," and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet. Copyright ?? 1981 AAAS.

  12. Io Plasma Torus Ion Composition: Voyager, Galileo, Cassini

    NASA Astrophysics Data System (ADS)

    Bagenal, Fran; Nerney, Edward; Steffl, Andrew Joseph

    2016-10-01

    With JAXA's Hisaki spacecraft in orbit around Earth gathering information on the Io plasma torus and NASA's Juno mission measuring plasma conditions in the jovian magnetosphere, the time is ripe for a re-evaluation of earlier observations of the plasma torus to assess evidence for temporal variations. In particular, we are interested in exploring the ion composition of the torus and whether there is evidence of the ultimate source – the volcanic gases from Io – have deviated from SO2. We use the latest CHIANTI 8.0 atomic database to analyze UV spectra of the torus from Voyager, Galileo and Cassini as well as with the physical chemistry model of Delamere, Steffl and Bagenal (2005). We find that contrary to earlier analyses of Voyager data (e.g. Shemansky 1987; 1988) that produced a composition requiring a neutral source of O/S~4, we find an ion composition that is consistent with the Cassini UVIS data (Steffl et al. 2004) and a neutral O/S~2, consistent with SO2.

  13. Encounter with Saturn - Voyager 1 imaging science results

    NASA Technical Reports Server (NTRS)

    Smith, B. A.; Soderblom, L.; Beebe, R.; Boyce, J.; Briggs, G.; Bunker, A.; Collins, S. A.; Hansen, C. J.; Johnson, T. V.; Mitchell, J. L.; Morrison, D.

    1981-01-01

    As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of 'ringlets', and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet.

  14. Encounter with saturn: voyager 1 imaging science results.

    PubMed

    Smith, B A; Soderblom, L; Beebe, R; Boyce, J; Briggs, G; Bunker, A; Collins, S A; Hansen, C J; Johnson, T V; Mitchell, J L; Terrile, R J; Carr, M; Cook, A F; Cuzzi, J; Pollack, J B; Danielson, G E; Ingersoll, A; Davies, M E; Hunt, G E; Masursky, H; Shoemaker, E; Morrison, D; Owen, T; Sagan, C; Veverka, J; Strom, R; Suomi, V E

    1981-04-10

    As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of "ringlets," and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet.

  15. Shared Voyage: Learning and Unlearning from Remarkable Projects

    NASA Technical Reports Server (NTRS)

    Laufer, Alexander; Post, Todd; Hoffman, Edward J.

    2005-01-01

    Shared Voyage is about four remarkable projects: the Advanced Composition Explorer (NASA), the Joint Air-to-Surface Standoff Missile (U.S. Air Force), the Pathfinder Solar-Powered Airplane (NASA), and the Advanced Medium Range Air-to-Air Missile (U.S.Air Force). Each project is presented as a case study comprised of stories collected from key members of the project teams. The stories found in the book are included with the purpose of providing an effective learning source for project management, encouraging the unlearning of outdated project management concepts, and enhancing awareness of the contexts surrounding different projects. Significantly different from project concepts found in most project management literature, Shared Voyage highlights concepts like a will to win, a results-oriented focus, and collaboration through trust. All four project teams researched in this study applied similar concepts; however, they applied them differently, tailoring them to fit the context of their own particular projects. It is clear that the one best way approach which is still the prevailing paradigm in project management literature should be replaced by a new paradigm: Even though general project management principles exist, their successful application depends on the specifics of the situation.

  16. Voyager IRIS Measurements of Triton's Thermal Emission: Impllications for Pluto?

    NASA Astrophysics Data System (ADS)

    Stansberry, John A.; Spencer, John; Linscott, Ivan

    2015-11-01

    The New Horizons Pluto encounter data set includes unique observations obtained using the Radio Science experiment to measure the night-side thermal emission at centimeter wavelengths, well beyond the emission peak (in the 70 to 100 micron range). 26 years ago the Voyager 2 Infrared Interferometer Spectrometer (IRIS) obtained spectra in the 30 - 50 micron wavelength range to try and detect thermal emission from Pluto's sibling, Triton. Conrath etal. (1989) analyzed 16 of the IRIS spectra of Triton's dayside and derived a weak limit of 36 K - 41 K. We have analysed those, and an additional 75 spectra, to refine the limits on the temperature of Triton's surface, and to explore diurnal differences in the thermal emission. Triton results from other Voyager instruments provide important constraints on our interpretation of the IRIS data, as do Spitzer measurements of Pluto's thermal emission.For unit-emissivity, average temperature is 34 K, inconsistent with the pressure of Triton's atmosphere (13 - 19 microbar), the presence of beta-phase nitrogen ice on the surface, and the likely presence ofwarm regions on the surface. The atmospheric pressure requires nitrogen ice temperatures of 37.4 K - 38.1 K, which in turn requires emissivity of 0.31--0.53. Such a low emissivity in this spectral region might be expected if the surface is dominated by nitrogen or methane ice. Averages of data subsets show evidence for brightness temperature variations across Triton's surface. Surprisingly, the data seem to indicate that Triton's nightside equatorial region was warmer than on the dayside.These Voyager results for Triton provide a useful context for interpreting New Horizons and ALMA observations of emission from Pluto in the sub-millimeter and centimeter region. JWST will be capable of detecting Triton's and Pluto's 10 - 28 micron thermal emission, although scattered light from Neptune may be an issue for the Triton. Combined with new capabilities of ALMA to measure the sub

  17. The voyager 2 encounter with the neptunian system.

    PubMed

    Stone, E C; Miner, E D

    1989-12-15

    An overview of the Voyager 2 encounter with Neptune is presented, including a brief discussion of the trajectory, the planned observations, and highlights of the results described in the 11 companion papers. Neptune's blue atmosphere has storm systems reminiscent of those in Jupiter's atmosphere. An optically thin methane ice cloud exists near the 1.5-bar pressure level, and an optically thick cloud exists below 3 bars. Neptune's magnetic field is highly tilted and offset from the planet's center; it rotates with a period of 16.11 hours. Two narrow and two broad rings circle the planet; the outermost of these rings has three optically thicker arc segments. Six new moons were discovered in circular prograde orbits, all well inside Triton's retrograde orbit. Triton has a highly reflective and geologically young surface, a thin nitrogen atmosphere, and at least two active geyser-like plumes.

  18. The Voyager 2 encounter with the Neptunian system

    SciTech Connect

    Stone, E.C.; Miner, E.D. )

    1989-12-15

    An overview of the Voyager 2 encounter with Neptune is presented, including a brief discussion of the trajectory, the planned observations, and highlights of the results described in the 11 companion papers. Neptune's blue atmosphere has storm systems reminiscent of those in Jupiter's atmosphere. An optically thin methane ice cloud exists near the 1.5-bar pressure level, and an optically thick cloud exists below 3 bars. Neptune's magnetic field is highly tilted and offset from the planet's center; it rotates with a period of 16.11 hours. Two narrow and two broad rings circle the planet; the outermost of these rings has three optically thicker arc segments. Six moons were discovered in circular prograde orbits, all well inside Triton's retrograde orbit. Triton has a highly reflective and geologically young surface, a thin nitrogen atmosphere, and at least two active geyser-like plumes.

  19. Voyager observations of dust scattering near the Coalsack nebula

    NASA Technical Reports Server (NTRS)

    Murthy, Jayant; Henry, R. C.; Holberg, J. B.

    1994-01-01

    We present the results of four observations of the sky in the direction of the Coalsack nebula. These observations were made using the ultraviolet spectrometers aboard the two Voyager spacecraft in the spectral range between 912 and 1600 A. Intense diffuse emission with a spectrum characteristic of an early B star was observed in all four targets, which we interpret as starlight forward scattered by interstellar dust in the foreground of the main mass of the Coalsack. While more detailed modeling is necessary to derive values for the optical constants of the dust grains, our data indicate that there is no decrease in the albedo toward shorter wavelengths, arguing that the far-ultraviolet rise in the interstellar extinction curve is due to an increasing number density of small particles rather than to a new population of low albedo grains.

  20. Plasma waves near saturn: initial results from voyager 1.

    PubMed

    Gurnett, D A; Kurth, W S; Scarf, F L

    1981-04-10

    The Voyager 1 plasma wave instrument detected many familiar types of plasma waves during the encounter with Saturn, including ion-acoustic waves and electron plasma oscillations upstream of the bow shock, an intense burst of electrostatic noise at the shock, and chorus, hiss, electrostatic electron cyclotron waves, and upper hybrid resonance emissions in the inner magnetosphere. A clocklike Saturn rotational control of low-frequency radio emissions was observed, and evidence was obtained of possible control by the moon Dione. Strong plasma wave emissions were detected at the Titan encounter indicating the presence of a turbulent sheath extending around Titan, and upper hybrid resonance measurements of the electron density show the existence of a dense plume of plasma being carried downstream of Titan by the interaction with the rapidly rotating magnetosphere of Saturn.

  1. Magnetic field studies at jupiter by voyager 1: preliminary results.

    PubMed

    Ness, N F; Acuna, M H; Lepping, R P; Burlaga, L F; Behannon, K W; Neubauer, F M

    1979-06-01

    Results obtained by the Goddard Space Flight Center magnetometers on Voyager 1 are described. These results concern the large-scale configuration of the Jovian bow shock and magnetopause, and the magnetic field in both the inner and outer magnetosphere. There is evidence that a magnetic tail extending away from the planet on the nightside is formed by the solar wind-Jovian field interaction. This is much like Earth's magnetosphere but is a new configuration for Jupiter's magnetosphere not previously considered from earlier Pioneer data. We report on the analysis and interpretation of magnetic field perturbations associated with intense electrical currents (approximately 5 x 10(6) amperes) flowing near or in the magnetic flux tube linking Jupiter with the satellite Jo and induced by the relative motion between Io and the corotating Jovian magnetosphere. These currents may be an important source of heating the ionosphere and interior of Io through Joule dissipation.

  2. Extreme ultraviolet observations from voyager 1 encounter with jupiter.

    PubMed

    Broadfoot, A L; Belton, M J; Takacs, P Z; Sandel, B R; Shemansky, D E; Holberg, J B; Ajello, J M; Atreya, S K; Donahue, T M; Moos, H W; Bertaux, J L; Blamont, J E; Strobel, D F; McConnell, J C; Dalgarno, A; Goody, R; McElroy, M B

    1979-06-01

    Observations of the optical extreme ultraviolet spectrum of the Jupiter planetary system during the Voyager 1 encounter have revealed previously undetected physical processes of significant proportions. Bright emission lines of S III, S IV, and O III indicating an electron temperature of 10(5) K have been identified in preliminary analyses of the Io plasma torus spectrum. Strong auroral atomic and molecular hydrogen emissions have been observed in the polar regions of Jupiter near magnetic field lines that map the torus into the atmosphere of Jupiter. The observed resonance scattering of solar hydrogen Lyman alpha by the atmosphere of Jupiter and the solar occultation experiment suggest a hot thermosphere (>/= 1000 K) wvith a large atomic hydrogen abundance. A stellar occultation by Ganymede indicates that its atmosphere is at most an exosphere.

  3. Magnetic field studies at Jupiter by Voyager 1 - Preliminary results

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Acuna, M. H.; Lepping, R. P.; Burlaga, L. F.; Behannon, K. W.; Neubauer, F. M.

    1979-01-01

    Results obtained by the Goddard Space Flight Center magnetometers on Voyager 1 are described. These results concern the large-scale configuration of the Jovian bow shock and magnetopause, and the magnetic field in both the inner and outer magnetosphere. There is evidence that a magnetic tail extending away from the planet on the nightside is formed by the solar wind-Jovian field interaction. This is much like earth's magnetosphere but is a new configuration for Jupiter's magnetosphere not previously considered from earlier Pioneer data. The analysis and interpretation of magnetic field perturbations associated with intense electrical currents (approximately 5 million amperes) flowing near or in the magnetic flux tube linking Jupiter with the satellite Io and induced by the relative motion between Io and the corotating Jovian magnetosphere are reported. These currents may be an important source of heating the ionosphere and interior of Io through Joule dissipation.

  4. The voyager 2 encounter with the neptunian system.

    PubMed

    Stone, E C; Miner, E D

    1989-12-15

    An overview of the Voyager 2 encounter with Neptune is presented, including a brief discussion of the trajectory, the planned observations, and highlights of the results described in the 11 companion papers. Neptune's blue atmosphere has storm systems reminiscent of those in Jupiter's atmosphere. An optically thin methane ice cloud exists near the 1.5-bar pressure level, and an optically thick cloud exists below 3 bars. Neptune's magnetic field is highly tilted and offset from the planet's center; it rotates with a period of 16.11 hours. Two narrow and two broad rings circle the planet; the outermost of these rings has three optically thicker arc segments. Six new moons were discovered in circular prograde orbits, all well inside Triton's retrograde orbit. Triton has a highly reflective and geologically young surface, a thin nitrogen atmosphere, and at least two active geyser-like plumes. PMID:17755996

  5. The Voyager 2 encounter with the Neptunian system

    NASA Technical Reports Server (NTRS)

    Stone, E. C.; Miner, E. D.

    1989-01-01

    An overview of the Voyager 2 encounter with Neptune is presented, including a brief discussion of the trajectory, the planned observations, and highlights of the results described in the 11 companion papers. Neptune's blue atmosphere has storm systems reminiscent of those in Jupiter's atmosphere. An optically thin methane ice cloud exists near the 1.5-bar pressure level, and an optically thick cloud exists below 3 bars. Neptune's magnetic field is highly tilted and offset from the planet's center; it rotates with a period of 16.11 hours. Two narrow and two broad rings circle the planet; the outermost of these rings has three optically thicker arc segments. Six new moons were discovered in circular prograde orbits, all well inside Triton's retrograde orbit. Triton has a highly reflective and geologically young surface, a thin nitrogen atmosphere, and at least two active geyser-like plumes.

  6. The thermal structure of Triton's atmosphere - Pre-Voyager models

    NASA Astrophysics Data System (ADS)

    McKay, C. P.; Pollack, J. B.; Zent, A. P.; Cruikshank, D. P.; Courtin, R.

    1989-08-01

    Spectral data from earth observations have indicated the presence of N2 and CH4 on Triton. This paper outlines the use of the 1-D radiative-convective model developed for Titan to calculate the current pressure of N2 and CH4 on Triton. The production of haze material is obtained by scaling down from the Titan value. Results and predictions for the Voyager Triton encounter are as follows: A N2-CH4 atmosphere on Triton is thermodynamically self consistent and would have a surface pressure of approximately 50 millibar; due to the chemically produced haze, Triton has a hot atmosphere with a temperature of approximately 130 K; Triton's troposphere is a region of saturation of the major constituent of the atmosphere, N2.

  7. Mapping the Galilean satellites of Jupiter with Voyager data

    NASA Astrophysics Data System (ADS)

    Batson, R. M.; Bridges, P. M.; Inge, J. L.; Isbell, C.; Masursky, H.; Strobell, M. E.; Tyner, R. L.

    1980-10-01

    The four Galilean satellites of Jupiter are being mapped using image data from the Voyager 1 and 2 spacecraft. The maps are published at several scales and in several versions. Preliminary maps at 1:25,000,000 - required for mission planning and preliminary science reports - were compiled with three weeks of data acquisition and have been published. Later maps incorporate photogrammetric triangulations. One of these, a color version of Io, has been completed at 1:25,000,000. The black-and-white versions are being produced at scales of 1:15,000,000, 1:5,000,000, and 1:2,000,000. The largest scale is applied only where the resolution justifies it. Although stereoscopic measurements were not possible, some relief information can be obtained from measurements of limb profiles and shadows.

  8. Studies of the interplanetary magnetic field: IMP's to Voyager

    NASA Technical Reports Server (NTRS)

    Ness, Norman F.

    1987-01-01

    During the last two decades, spacecraft projects and individual experiments for which Frank McDonald was a leader have contributed very significantly to the current understanding of the structure of interplanetary space and the correlation between solar and interplanetary disturbances. Studies on the IMP, HELIOS, and Pioneer spin-stabilized spacecraft and the larger attitude-stabilized Voyager spacecraft have provided data sets from which the modern view of the heliosphere has evolved. That concept in which the inner solar system is shown to be dominated by individual streams associated with specific source regions on the Sun is illustrated. As these high-speed streams overtake the preexisting solar plasma, they coalesce and modify the characteristics so that at larger heliocentric distances, these disturbances appear as radially propagating concentric shells of compressed magnetic fields and enhanced fluctuations

  9. Planetary radio astronomy receiver. [experiment on Voyager spacecraft

    NASA Technical Reports Server (NTRS)

    Lang, G. J.; Peltzer, R. G.

    1977-01-01

    The planetary radio astronomy (PRA) experiment on the Voyager spacecraft will measure the amplitude, spectrum, time variations, and polarization of radio emissions over a frequency range of 1.2 kHz to 40.5 MHz with the aid of the PRA receiver (PRAR) and two 10-m orthogonal monopoles. Sensitivity and dynamic range will allow observation of a wide range of Jovian emissions from near earth to encounter. This paper describes the system elements, including the preamp/attenuator/calibrator, the LF polarization discriminator, the four LF-IF amplifier stages, the HF polarization discriminator, the translation LO, the log-IF and detector, the frequency synthesizer, the data processor, control system, power supply, and antennas.

  10. Energetic charged particles in Saturn's magnetosphere: Voyager 2 results

    SciTech Connect

    Vogt, R.E.; Chenette, D.L.; Cummings, A.C.; Garrard, T.L.; Stone, E.C.; Schardt, A.W.; Trainor, J.H.; Lal, N.; McDonald, F.B.

    1982-01-29

    Results from the cosmic-ray system on Voyager 2 in Saturn's magnetosphere are presented. During the inbound pass through the outer magnetosphere, the greater than or equal to 0.43-million-electron-volt proton flux was more intense, and both the proton and electron fluxes were more varible, than previously observed. These changes are attributed to the influence on the magnetosphere of variations in the solar wind conditions. Outbound, beyond 18 Saturn radii, impulsive bursts of 0.14- to > 1.0-million-electron-volt electrons were observed. In the inner magnetosphere, the charged particle absorption signatures of Mimas, Enceladus, and Tethys are used to constrain the possible tilt and offset of Saturn's internal magnetic dipole. At approx. 3 Saturn radii, a transient decrease was observed in the electron flux which was not due to Mimas. Characteristics of this decrease suggest the existence of additional material, perhaps another satellite, in the orbit of Mimas.

  11. Uranus photochemistry and prospects for Voyager 2 at Neptune

    NASA Technical Reports Server (NTRS)

    Atreya, S. K.

    1990-01-01

    CH4 is the only photochemically active constituent in the atmospheres of Uranus and Neptune. NH3, H2O and H2S are all removed by condensation at pressures greater than 1.5 bars. Although the bulk mole fraction (about 2 percent) of CH4 is 20-30 times its solar value on both planets, it drops to its saturation limit (about 0.0001) at the Uranus tropopause, but remains high (about 2 percent) at the Neptune tropopause. This results in much greater mixing ratios of the product hydrocarbons in the stratosphere of Neptune. On both planets, the photolysis products of CH4 undergo condensation near the tropopause and the upper stratosphere. Voyager observations of the hydrocarbons at Uranus and those planned at Neptune are discussed, along with their implications for upper-atmospheric physics and thermochemistry.

  12. Energetic Charged Particles in Saturn's Magnetosphere: Voyager 2 Results.

    PubMed

    Vogt, R E; Chenette, D L; Cummings, A C; Garrard, T L; Stone, E C; Schardt, A W; Trainor, J H; Lal, N; McDonald, F B

    1982-01-29

    Results from the cosmic-ray system on Voyager 2 in Saturn's magnetosphere are presented. During the inbound pass through the outer magnetosphere, the >/= 0.43-million-electron-volt proton flux was more intense, and both the proton and electron fluxes were more variable, than previously observed. These changes are attributed to the influence on the magnetosphere of variations in the solar wind conditions. Outbound, beyond 18 Saturn radii, impulsive bursts of 0.14- to > 1.0- million-electron-volt electrons were observed. In the inner magnetosphere, the charged particle absorption signatures of Mimas, Enceladus, and Tethys are used to constrain the possible tilt and offset of Saturn's internal magnetic dipole. At approximately 3 Saturn radii, a transient decrease was observed in the electron flux which was not due to Mimas. Characteristics of this decrease suggest the existence of additional material, perhaps another satellite, in the orbit of Mimas.

  13. Energetic Charged Particles in Saturn's Magnetosphere: Voyager 1 Results.

    PubMed

    Vogt, R E; Chenette, D L; Cummings, A C; Garrard, T L; Stone, E C; Schardt, A W; Trainor, J H; Lal, N; McDonald, F B

    1981-04-10

    Voyager 1 provided the first look at Saturn's magnetotail and magnetosphere during relatively quiet interplanetary conditions. This report discusses the energetic particle populations of the outer magnetosphere of Saturn and absorption features associated with Titan and Rhea, and compares these observations with Pioneer 11 data of a year earlier. The trapped proton fluxes had soft spectra, represented by power laws E(-gamma) in kinetic energy E, with gamma approximately 7 in the outer magnetosphere and gamma approximately 9 in the magnetotail. Structure associated with the magnetotial was observed as close as 10 Saturn radii (R(s)) on the outbound trajectory. The proton and electron fluxes in the outer magnetosphere and in the magnetotail were variable and appeared to respond to changes in interplanetary conditions. Protons with energies >/= 2 million electron volts had free access to the magnetosphere from interplanetary space and were not stably trapped outside approximately 7.5 R(s).

  14. The extraordinary voyages through the region of the giant planets

    NASA Astrophysics Data System (ADS)

    Danloux-Dumesnils, M.

    1983-01-01

    The astronautical achievements necessary for guiding Pioneer 10 and 11 and Voyager I and II to the giant planets are reviewed. The spacecraft were equipped with rocket exhausts for both orbital corrections and revolution about their axis. Calculations for the Hohmann transfer orbit are performed, noting that the most efficient trajectory to Jupiter is elliptical, and that the launch dates were strictly circumscribed by the condition that the heliocentric position of Jupiter was necessarily 97 deg longitudinally greater than earth's at the launch. Considerations given to the transition of the dominant gravitational force from the sun to Jupiter are described, together with the calculation procedures. The encounters of each planetary body (and their moons) by each of the probes is detailed. The benefits of gravity assists for gaining velocity are outlined, and the bext favorable window for another grand tour is identified in the 1993-1997 interval

  15. Pioneer and voyager observations of the solar wind at large heliocentric distances and lattitudes

    SciTech Connect

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

    1989-03-01

    The Pioneer 10, 11, and Voyager 2 spacecraft are well suited for exploring spatial gradients in the distant solar wind. Between 1984 and 1986 Pioneer 11 and Voyager 2 were located at nearly the same heliocentric distance (approx. =20 AU) and longitude but were widely separated in latitude; Pioneer 11 was at a heliographic latitude of greater than or equal to15/sup 0/ while Voyager 2 was near the solar equator. Pioneer 10 was located near the solar equator but at a considerably greater heliocentric distance (approx. =40 AU). IMP observations at 1 AU provide an inner heliosphere baseline.

  16. Pioneer and Voyager observations of the solar wind at large heliocentric distances and latitudes

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

    Data obtained from the electrostatic analyzers aboard the Pioneer 10 and 11 spacecraft and from the Faraday cup aboard Voyager 2 were used to study spatial gradients in the distant solar wind. Prior to mid-1985, both spacecraft observed nearly identical solar wind structures. After day 150 of 1985, the velocity structure at Voyager 2 became flatter, and the Voyager 2 velocities were smaller than those observed by Pioneer 11. It is suggested that these changes in the solar wind at low latitudes may be related to a change which occurred in the coronal hole structure in early 1985.

  17. Voyager 2 in the Uranian system: Imaging science results

    USGS Publications Warehouse

    Smith, B.A.; Soderblom, L.A.; Beebe, R.; Bliss, D.; Boyce, J.M.; Brahic, A.; Briggs, G.A.; Brown, R.H.; Collins, S.A.; Cook, A.F.; Croft, S.K.; Cuzzi, J.N.; Danielson, G.E.; Davies, M.E.; Dowling, T.E.; Godfrey, D.; Hansen, C.J.; Harris, M. Camille; Hunt, G.E.; Ingersoll, A.P.; Johnson, T.V.; Krauss, R.J.; Masursky, H.; Morrison, D.; Owen, editors, Timothy W.; Plescia, J.B.; Pollack, James B.; Porco, C.C.; Rages, K.; Sagan, C.; Shoemaker, E.M.; Sromovsky, L.A.; Stoker, C.; Strom, R.G.; Suomi, V.E.; Synnott, S.P.; Terrile, R.J.; Thomas, P.; Thompson, W.R.; Veverka, J.

    1986-01-01

    Voyager 2 images of the southern hemisphere of Uranus indicate that submicrometersize haze particles and particles of a methane condensation cloud produce faint patterns in the atmosphere. The alignment of the cloud bands is similar to that of bands on Jupiter and Saturn, but the zonal winds are nearly opposite. At mid-latitudes (-70?? to -27??), where winds were measured, the atmosphere rotates faster than the magnetic field; however, the rotation rate of the atmosphere decreases toward the equator, so that the two probably corotate at about -20??. Voyager images confirm the extremely low albedo of the ring particles. High phase angle images reveal on the order of 10 2 new ringlike features of very low optical depth and relatively high dust abundance interspersed within the main rings, as well as a broad, diffuse, low optical depth ring just inside the main ring system. Nine of the newly discovered small satellites (40 to 165 kilometers in diameter) orbit between the rings and Miranda; the tenth is within the ring system. Two of these small objects may gravitationally confine the ?? ring. Oberon and Umbriel have heavily cratered surfaces resembling the ancient cratered highlands of Earth's moon, although Umbriel is almost completely covered with uniform dark material, which perhaps indicates some ongoing process. Titania and Ariel show crater populations different from those on Oberon and Umbriel; these were probably generated by collisions with debris confined to their orbits. Titania and Ariel also show many extensional fault systems; Ariel shows strong evidence for the presence of extrusive material. About half of Miranda's surface is relatively bland, old, cratered terrain. The remainder comprises three large regions of younger terrain, each rectangular to ovoid in plan, that display complex sets of parallel and intersecting scarps and ridges as well as numerous outcrops of bright and dark materials, perhaps suggesting some exotic composition.

  18. A Voyage through Scales - Water in terrestrial systems

    NASA Astrophysics Data System (ADS)

    Roth, Kurt

    2015-04-01

    Terrestrial systems - a conglomerate that includes sediments, soils, and vegetation - are the third large compartment of our environment, besides the fluid systems atmosphere and ocean. All of them exhibit structures with a range of spatial and temporal scales that cover at least 9 orders of magnitude. There is a fundamental difference, however. For the fluid systems, structures and flow are one, with structures generated by the nonlinear nature of the flow and manifest in it. In contrast, the structures of terrestrial systems are predominantly formed by processes whose time scales are many orders of magnitude larger than those of the flow and transport within them. During our voyage, we will first consider the role of terrestrial systems in Earth's environmental machinery, will then stroll through their intricate multiscale architecture that covers some 14 orders of magnitude in space, and indeed also in time, have a short glimpse at the nature of the processes, predominantly the flow of water with just a nod to transport and interactions, and will finally formulate a key question: "Is an effective representation of processes in terrestrial systems possible, at a chosen scale of interest, and if so, how can it be gained?" There is no straight answer to this and we will visit several of its aspects - dissipative processes, representative and maximal averaging volumes, and time-scales -, will look at successes and failures, and will finally glance over to the working crews that attempt to blaze a way forward by dense observation networks, data assimilation, and high-performance computing. This voyage will be through Earth's terrestrial systems, with a focus on soils and porous media. It should also be informative for all who are facing nonlinear processes in hierarchically heterogeneous architectures.

  19. An Explanation for the Recent Voyager 1 Observations

    NASA Astrophysics Data System (ADS)

    Fisk, L. A.; Gloeckler, G.

    2013-12-01

    A model is presented that can account for the recent Voyager 1 observations: (1) beyond ~113 AU from the Sun, the anisotropy of low-energy ions becomes very small in all directions, which has been interpreted as indicating that the solar wind flow speed has decreased to near zero; (2) at ~120 AU, anomalous cosmic rays (ACRs) are accelerated to their highest energies; (3) at ~122 AU, there is a precipitous decrease both in ACRs and in termination shock particles (TSPs) that are convected downstream from the termination shock; and (4) coincident with the decrease in ACRs and TSPs there is an commensurate increase in the magnetic field, but no change in the magnetic field direction. In this presentation, the low-energy anisotropy observations are interpreted as implying, not that the solar wind flow speed has decreased to near zero, but rather that the solar wind flow is closely aligned with the magnetic field direction, which is observed to be in the azimuthal direction. A simple model for the heliosheath is then constructed, based on the anisotropy observations and the observational evidence that the dominant pressure is contained in pickup ions, TSP, and ACRs. The model predicts that there are jets of supersonic and super-Alfvénic solar wind flowing along the flanks of the heliosheath, stretching and opening the heliosheath magnetic field into the interstellar medium. TSPs and ACRs that are accelerated in the nose region can easily escape along the magnetic field in the open region of the heliosheath, resulting in the precipitous decrease in the intensity of TSPs and ACRs, and offering an explanation for other Voyager 1 and IBEX observations.

  20. Voyager 2 in the uranian system: imaging science results.

    PubMed

    Smith, B A; Soderblom, L A; Beebe, R; Bliss, D; Boyce, J M; Brahic, A; Briggs, G A; Brown, R H; Collins, S A; Cook, A F; Croft, S K; Cuzzi, J N; Danielson, G E; Davies, M E; Dowling, T E; Godfrey, D; Hansen, C J; Harris, C; Hunt, G E; Ingersoll, A P; Johnson, T V; Krauss, R J; Masursky, H; Morrison, D; Owen, T; Plescia, J B; Pollack, J B; Porco, C C; Rages, K; Sagan, C; Shoemaker, E M; Sromovsky, L A; Stoker, C; Strom, R G; Suomi, V E; Synnott, S P; Terrile, R J; Thomas, P; Thompson, W R; Veverka, J

    1986-07-01

    Voyager 2 images of the southern hemisphere of Uranus indicate that submicrometersize haze particles and particles of a methane condensation cloud produce faint patterns in the atmosphere. The alignment of the cloud bands is similar to that of bands on Jupiter and Saturn, but the zonal winds are nearly opposite. At mid-latitudes (-70 degrees to -27 degrees ), where winds were measured, the atmosphere rotates faster than the magnetic field; however, the rotation rate of the atmosphere decreases toward the equator, so that the two probably corotate at about -20 degrees . Voyager images confirm the extremely low albedo of the ring particles. High phase angle images reveal on the order of 10(2) new ringlike features of very low optical depth and relatively high dust abundance interspersed within the main rings, as well as a broad, diffuse, low optical depth ring just inside the main rings system. Nine of the newly discovered small satellites (40 to 165 kilometers in diameter) orbit between the rings and Miranda; the tenth is within the ring system. Two of these small objects may gravitationally confine the e ring. Oberon and Umbriel have heavily cratered surfaces resembling the ancient cratered highlands of Earth's moon, although Umbriel is almost completely covered with uniform dark material, which perhaps indicates some ongoing process. Titania and Ariel show crater populations different from those on Oberon and Umbriel; these were probably generated by collisions with debris confined to their orbits. Titania and Ariel also show many extensional fault systems; Ariel shows strong evidence for the presence of extrusive material. About halfof Miranda's surface is relatively bland, old, cratered terrain. The remainder comprises three large regions of younger terrain, each rectangular to ovoid in plan, that display complex sets of parallel and intersecting scarps and ridges as well as numerous outcrops of bright and dark materials, perhaps suggesting some exotic

  1. Voyager aircraft return from non-stop trip around the world

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The Voyager aircraft circles before landing at Edwards Air Force Base, Edwards, California, to complete it's record breaking, nonstop unfueled flight around the world. The Voyager landed at Edwards at 8:06 a.m. PST Dec. 23, 1986, after a nine-day flight. Richard Rutan and Jeana Yeager piloted the aircraft from a cramped cockpit. Voyager's takeoff weight was more than 10 times the structural weight, but its drag was lower than almost any other powered aircraft. The aircraft's design and light-weight structural materials allowed it to carry an unprecedented amount of fuel on its 25,000 mile flight. Voyager took off from Edwards Dec. 14, and traveled at an average speed of 115.8 mph. The 9 day, 3 minute, 44 sec. flight nearly doubled the previous distance record set in 1962 by a USAF/Boeing B-52H.

  2. The fate of the bird specimens from Cook's voyages possessed by Sir Joseph Banks.

    PubMed

    Medway, David G

    2009-10-01

    Joseph Banks possessed the greater part of the zoological specimens collected on James Cook's three voyages round the world (1768-1780). In early 1792, Banks divided his zoological collection between John Hunter and the British Museum. It is probable that those donations together comprised most of the zoological specimens then in the possession of Banks, including such bird specimens as remained of those that had been collected by himself and Daniel Solander on Cook's first voyage, and those that had been presented to him from Cook's second and third voyages. The bird specimens included in the Banks donations of 1792 became part of a series of transactions during the succeeding 53 years which involved the British Museum, the Royal College of Surgeons of England, and William Bullock. It is a great pity that, of the extensive collection of bird specimens from Cook's voyages once possessed by Banks, only two are known with any certainty to survive.

  3. NASA Now: Space Science: Voyager’s Grand Tour of the Solar System

    NASA Video Gallery

    Planetary scientist Lou Mayo discusses what we’re learning from the Voyager missions, where the two spacecraft currently are located, and some of the incredible discoveries made on the long journ...

  4. Infrared images of Jupiter at 5-micrometer wavelength during the Voyager 1 encounter

    NASA Technical Reports Server (NTRS)

    Terrile, R. J.; Capps, R. W.; Backman, D. E.; Becklin, E. E.; Cruikshank, D. P.; Beichman, C. A.; Brown, R. H.; Westphal, J. A.

    1979-01-01

    A coordinated program to observe Jupiter at high spatial resolution in the 5-micrometer wavelength region was undertaken to support Voyager 1 imaging and infrared radiation experiment targeting. Jupiter was observed over a 5-month period from Palomar and Mauna Kea observatories. The frequency of observations allowed the selection of interesting areas for closer Voyager examination and also provided good short-term monitoring of variations in cloud morphology. Significant global changes in the 5-micrometer distribution are seen over this time period.

  5. 33 CFR 157.162 - Crude oil washing during a voyage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Crude oil washing during a voyage... OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.162 Crude oil washing... § 157.10c(b)(2) shall ensure that each cargo tank that is crude oil washed during a voyage other than...

  6. 33 CFR 157.162 - Crude oil washing during a voyage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Crude oil washing during a voyage... OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.162 Crude oil washing... § 157.10c(b)(2) shall ensure that each cargo tank that is crude oil washed during a voyage other than...

  7. Vertical mixing and methane photochemistry in the atmosphere of Uranus: Analysis of Voyager UVS occultation experiments

    NASA Technical Reports Server (NTRS)

    Bishop, James

    1991-01-01

    Extensive capabilities were developed in the analysis of ultraviolet spectrometer (UVS) absorptive lightcurves. The application of these capabilities to the Voyager UVS data sets from Uranus and Neptune has provided significant findings regarding the stratospheres of these planets. In particular, the direct comparison between photochemical models and UVS measurements accomplished by these efforts is unique, and it helps to guarantee that the information returned by the Voyager 2 spacecraft is being used to the fullest extent possible.

  8. Infrared images of jupiter at 5-micrometer wavelength during the voyager 1 encounter.

    PubMed

    Terrile, R J; Capps, R W; Backman, D E; Becklin, E E; Cruikshank, D P; Beichman, C A; Brown, R H; Westphal, J A

    1979-06-01

    A coordinated program to observe Jupiter at high spatial resolution in the 5-micrometer wavelength region was undertaken to support Voyager 1 imaging and infrared radiation experiment targeting. Jupiter was observed over a 5-month period from Palomar and Mauna Kea observatories. The frequency of observations allowed the selection of interesting areas for closer Voyager examination and also provided good short-term monitoring of variations in cloud morphology. Significant global changes in the 5-micrometer distribution are seen over this time period.

  9. Synthetic Micro/Nanomachines and Their Applications: Towards 'Fantastic Voyage'

    NASA Astrophysics Data System (ADS)

    Gao, Wei

    The 1966 movie Fantastic Voyage captured the world's imagination, portraying a tiny submarine navigating through the human bloodstream and treating life-threatening medical conditions. My PhD research focuses on the synthetic nano/microscale machines to realize the Fantastic Voyage vision. Various biomedical and environmental areas would benefit from the developments of efficient fuel-free and fuel-driven nano/microscale machines. The polymer-based catalytic tubular microengine is synthesized using a template based electrodeposition method. The oxygen bubble propelled microengine harvests the energy from chemical fuels (such as H2O2) and displays very efficient propulsion. It can serve as an ideal platform for diverse biomedical and environmental applications. For example, lectin modified polyaniline based microengines can be used for selective bacteria (E. Coli) isolation from food, clinical and environmental samples; poly(3-aminophenylboronic acid)/Ni/Pt microengine itself provides the 'built in' glucose recognition capability for 'on-the-fly' capture, transport and release of yeast cells. A series of micromotors which can be self-propelled in natural environments without additional chemical fuels are developed, holding great promise for in vivo biomedical applications: the polyaniline/zinc microrockets display effective autonomous motion in extreme acidic environments (such as human stomach); the Al-Ga/Ti based Janus micromotor can be propelled by the hydrogen bubbles generated from the rapid aluminum and water reaction; alkanethiols modified seawater-driven Mg Janus micromotors, which utilize macrogalvanic corrosion and chloride pitting corrosion processes, can be used for environmental oil remediation. Magnetically powered nanoswimmers have attracted considerable attention due to their great biocompatibility. A high-speed magnetically-propelled nanowire swimmer which mimics swimming microorganisms by exploiting the flexible nanowire as artificial flagella

  10. Voyager Observations of the Color of Saturn's Ring

    NASA Technical Reports Server (NTRS)

    Estrada, Paul R.; Cuzzi, Jeffrey N.; Morrison, David (Technical Monitor)

    1994-01-01

    Previously unreduced high resolution Voyager 2 images of Saturn's main rings are used to generate reflectivity (I/F) profiles as a function of radius. Ratios of profiles taken from green, violet, orange, and UV filter images are then produced. The I/F ratios are diagnostic of composition, and provide us with information on the rings' present state of compositional evolution. The rings are extremely reddish in color which suggests that they could not be pure water ice. The most likely candidates for the non-icy components are silicates and organics. The sources of these pollutants are of extreme importance in determining the compositional history of the rings. The radial profiles of ring color ratio exhibit several very interesting properties: (a) broad-scale, fairly smooth, color variations which are only weakly correlated with underlying ring structure (optical depth variations) across the outer C ring and inner B ring as well as the Cassini division region. These variations are probably consistent with ballistic transport; (b) fine-scale, noise-Like (but unquestionably real) color variations across at least the outer two-thirds of the B ring. Not only the "redness" but the spectral shape varies. These variations are currently unexplained. Groundbased spectroscopic observations should be pursued to study the implied compositional heterogeneities on at least the larger scales. This data set will be used for modeling of the color and composition of the main rings using ballistic transport and radiative transfer theories.

  11. Current Sheets in the Heliosheath: Voyager 1, 2009

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Ness, N. F.

    2011-01-01

    We identified all of the current sheets for which we have relatively complete and accurate magnetic field (B) data from Voyager 1 (V1) from days of year (DOYs) 1 to 331, 2009, which were obtained deep in the heliosheath between 108.5 and 111.8 AU. Three types of current sheets were found: (1) 15 proton boundary layers (PBLs), (2) 10 and 3 magnetic holes and magnetic humps, respectively, and (3) 3 sector boundaries. The magnetic field strength changes across PBL, and the profile B(t) is linearly related to the hyperbolic tangent function, but the direction of B does not change. For each of the three sector boundaries, B rotated in a plane normal to the minimum variance direction, and the component of B along the minimum variance direction was zero within the uncertainties, indicating that the sector boundaries were tangential discontinuities. The structure of the sector boundaries was not as simple as that for PBLs. The average thickness of magnetic holes and humps (approx.30 RL) was twice that of the PBLs (approx.15 RL). The average thickness of the current sheets associated with sector boundaries was close to the thickness of the PBLs. Our observations are consistent with the hypothesis that magnetic holes and humps are solitons, which are initiated by the mirror mode instability, and evolve by nonlinear kinetic plasma processes to pressure balanced structures maintained by magnetization currents and proton drift currents in the gradients of B.

  12. The source of Jovian auroral hiss observed by Voyager 1

    NASA Technical Reports Server (NTRS)

    Morgan, D. D.; Gurnett, D. A.; Kurth, W. S.; Bagenal, F.

    1994-01-01

    Observations of auroral hiss obtained from the Voyager 1 encounter with Jupiter have been reanalyzed. The Jovian auroral hiss was observed near the inner boundary of the warm Io torus and has a low-frequency cutoff caused by propagation near the resonance cone. A simple ray tracing procedure using an offset tilted dipole of the Jovian magnetic field is used to determine possible source locations. The results obtained are consistent with two sources located symmetrically with respect to the centrifugal equator along an L shell (L approximately = 5.59) that is coincident with the boundary between the hot and cold regions of the Io torus and is located just inward of the ribbon feature observed from Earth. The distance of the sources from the centrifugal equator is approximately 0.58 +/- 0.01 R(sub J). Based on the similarity to terrestrial auroral hiss, the Jovian is auroral hiss is believed to be generated by beams of low energy (approximately tens to thousands of eV) electrons. The low-frequency cutoff of the auroral hiss suggests that the electrons are accelerated near the inferred source region, possibly by parallel electric fields similar to those existing in the terrestrial auroral regions. A field-aligned current is inferred to exist at L shells just inward of the plasma ribbon. A possible mechanism for driving this current is discussed.

  13. Standing Alfven wave current system at Io - Voyager 1 observations

    NASA Technical Reports Server (NTRS)

    Acuna, M. H.; Ness, N. F.; Neubauer, F. M.

    1981-01-01

    The enigmatic control of the occurrence frequency of Jupiter's decametric emissions by the satellite Io has been explained theoretically on the basis of its strong electrodynamic interaction with the corotating Jovian magnetosphere leading to field-aligned currents connecting Io with the Jovian ionosphere. Direct measurements of the perturbation magnetic fields due to this current system were obtained by the Goddard Space Flight Center magnetic field experiment on Voyager 1 on March 5, 1979, when it passed within 20,500 km south of Io. An interpretation in the framework of Alfven waves radiated by Io leads to current estimates of 2.8 x 10 to the 6th A. A mass density of 7400-13,600 proton mass units/cu cm is derived, which compares very favorably with independent observations of the torus composition characterized by 7-9 proton mass units per electron for a local electron density of 1050-1500/cu cm. The power dissipated in the current system may be important for heating the Io heavy ion torus, inner magnetosphere, Jovian ionosphere, and possibly the ionosphere or even the interior of Io.

  14. Magnetic field experiment for Voyagers 1 and 2

    NASA Technical Reports Server (NTRS)

    Behannon, K. W.; Aluna, M. H.; Burlaga, L. F.; Lepping, R. P.; Ness, N. F.; Neubauer, F. M.

    1977-01-01

    The magnetic field experiment to be carried on the Voyager 1 and 2 missions consists of dual low field (LFM) and high field magnetometer (HFM) systems. The dual systems provide greater reliability and, in the case of the LFM's, permit the separation of spacecraft magnetic fields from the ambient fields. Additional reliability is achieved through electronics redundancy. The wide dynamic ranges of plus or minus 0.5G for the LFM's and plus or minus 20G for the HFM's, low quantization uncertainty of plus or minus 0.002 gamma in the most sensitive (plus or minus 8 gamma) LFM range, low sensor RMS noise level of 0.006 gamma, and use of data compaction schemes to optimize the experiment information rate all combine to permit the study of a broad spectrum of phenomena during the mission. Planetary fields at Jupiter, Saturn, and possibly Uranus; satellites of these planets; solar wind and satellite interactions with the planetary fields; and the large-scale structure and microscale characteristics of the interplanetary magnetic field are studied. The interstellar field may also be measured.

  15. Voyager photometry of surface features on Ganymede and Callisto

    NASA Technical Reports Server (NTRS)

    Squyres, S. W.; Veverka, J.

    1981-01-01

    Photometric properties of selected surface features on Ganymede and Callisto are studied, using Voyager images over phase angles from 10 to 124 deg, taken with a clear filter (effective wavelength of approximately 0.5 microns). Normal reflectances on Ganymede average 0.35 for the cratered terrain, and 0.44 for the grooved terrain; the ubiquitous cratered terrain on Callisto is 0.18. The photometric properties of these regions are described by a simple scattering function, where the function of the phase angle is qualitatively similar to that of the moon, i.e., concave upward. By contrast, bright craters on both satellites have functions of the phase angle which are concave downward. The scattering function is not Lambertian, and may be due to an admixture of a small amount of dark, opaque silicate grains with the frost deposits. The brightest craters on Callisto have reflectances which are 10% lower than the brightest craters on Ganymede, and both have similar scattering laws.

  16. The helium abundance of Uranus from Voyager measurements

    NASA Technical Reports Server (NTRS)

    Conrath, B.; Hanel, R.; Gautier, D.; Marten, A.; Lindal, G.

    1987-01-01

    Voyager radio-occultation and IR spectroscopy measurements are combined to infer an He mole fraction in the upper troposphere of Uranus of 0.152 + or - 0.033; the corresponding mass fraction is Y = 0.262 + or - 0.048. This value is in agreement with recent estimates of the solar He abundance, suggesting that He differentiation has not occurred on Uranus. Comparisons with values previously obtained for Jupiter and Saturn imply that migration of He toward the core began long ago on Saturn and may also have recently begun on Jupiter. The protosolar He abundance inferred from the Uranus measurements and from recent solar evolutionary models is used along with an assumed primordial He mass fraction of 0.23-0.24 to estimate a 3-4-percent enrichment of He in the interstellar medium between the big bang and the origin of the solar system. The result is in agreement with galactic chemical evolution models which include a substantial decrease in D during the evolutionary process.

  17. Particles and fields measurements at Neptune with Voyager 2

    NASA Technical Reports Server (NTRS)

    Krimigis, S. M.

    1992-01-01

    The first results of measurements performed on the Voyager 2 spacecraft with the Neptune system on August 24-28, 1989 are summarized. These include measurements of the magnetic field, plasma, energetic and high energy particles, plasma waves and radio emissions, and additional information relating to UV emissions. The planetary magnetic field outside about 4 R(N) may be described by an offset, tilted, dipole of moment 0.133 Gauss-R(N) exp 3; inside that distance the field is dominated by higher order terms. Plasma densities are found to be generally low (about 5 exp -3/cu cm), except at magnetic equatorial crossings when densities are up to about 1/cu cm. A variety of plasma wave emissions were seen, including chorus, hiss, electroncyclotron waves, and upper hybrid resonance in the inner magnetosphere. The measured flux of soft electrons and ions over the polar region of about 2 x 10 exp -3 erg/sq cm sec results in an estimated power input of about 3 x 10 exp 7 W, which is substantially less than that at other planets.

  18. Jupiter's Atmospheric Temperatures: From Voyager IRIS to Cassini CIRS

    NASA Technical Reports Server (NTRS)

    Simon-Miller, Amy A.; Conrath, Barney J.; Gierasch, Peter J.; Orton, Glenn S.; Achterberg, Richard K.; Flasar, F. Michael; Fisher, Brendan

    2004-01-01

    Retrievals run on Cassini Composite Infrared Spectrometer data obtained during the distant Jupiter flyby have been used to generate global temperature maps of the planet in the troposphere and stratosphere. Similar retrievals were performed on Voyager 1 IRIS data and have provided the first detailed IRIS map of the stratosphere. In both data sets, high latitude troposphere temperatures are presented for the first time, and the meridional gradients indicate the presence of circumpolar jets. Thermal winds were calculated for each data set and show strong vertical shears in the zonal winds at low latitudes. The temperatures retrieved from the two spacecraft were also compared with yearly ground-based data obtained over the intervening two decades. Tropospheric temperatures reveal gradual changes at low latitudes, with little obvious seasonal or short-term variation (Orton et al. 1994). Stratospheric temperatures show much more complicated behavior over short timescales, consistent with quasi-quadrennial oscillations at low latitudes, as suggested in prior analyses of shorter intervals of ground- based data (Orton et al. 1991, Friedson 1999). A scaling analysis indicates that meridional motions, mechanically forced by wave or eddy convergence, play an important role in modulating the temperatures and winds in the upper troposphere and stratosphere on seasonal and shorter time scales. At latitudes away from the equator, the mechanical forcing can be derived simply from a temporal record of temperature and its vertical derivative. Ground-based observations with improved vertical resolution and/or long-term monitoring from spacecraft are required for this purpose.

  19. Plasma observations near uranus: initial results from voyager 2.

    PubMed

    Bridge, H S; Belcher, J W; Coppi, B; Lazarus, A J; McNutt, R L; Olbert, S; Richardson, J D; Sands, M R; Selesnick, R S; Sullivan, J D; Hartle, R E; Ogilvie, K W; Sittler, E C; Bagenal, F; Wolff, R S; Vasyliunas, V M; Siscoe, G L; Goertz, C K; Eviatar, A

    1986-07-01

    Extensive measurements of low-energy positive ions and electrons in the vicinity of Uranus have revealed a fully developed magnetosphere. The magnetospheric plasma has a warm component with a temperature of 4 to 50 electron volts and a peak density of roughly 2 protons per cubic centimeter, and a hot component, with a temperature of a few kiloelectron volts and a peak density of roughly 0.1 proton per cubic centimeter. The warm component is observed both inside and outside of L = 5, whereas the hot component is excluded from the region inside of that L shell. Possible sources of the plasma in the magnetosphere are the extended hydrogen corona, the solar wind, and the ionosphere. The Uranian moons do not appear to be a significant plasma source. The boundary of the hot plasma component at L = 5 may be associated either with Miranda or with the inner limit of a deeply penetrating, solar wind-driven magnetospheric convection system. The Voyager 2 spacecraft repeatedly encountered the plasma sheet in the magnetotail at locations that are consistent with a geometric model for the plasma sheet similar to that at Earth.

  20. Voyager 2: energetic ions and electrons in the jovian magnetosphere.

    PubMed

    Vogt, R E; Cummings, A C; Garrard, T L; Gehrels, N; Stone, E C; Trainor, J H; Schardt, A W; Conlon, T F; McDonald, F B

    1979-11-23

    The Voyager 2 encounter has enhanced our understanding of earlier results and provided measurements beyond 160 Jupiter radii (R(J)) in the magnetotail. Significant fluxes of energetic sulfur and oxygen nuclei (4 to 15 million electron volts per nucleon) of Jovian origin were observed inside 25 R(J), and the gradient in phase space density at 12 R(J) indicates that the ions are diffusing inward. A substantially longer time delay versus distance was found for proton flux maxima in the active hemisphere in the magnetotail at Jovicentric longitudes lambda(III), = 260 degrees to 320 degrees than in the inactive hemisphere at lambda(III), = 85 degrees to l10 degrees . These delays can be related to the radial motion of plasma expanding into the magnetotail, and differences in the expansion speeds between the active and inactive hemispheres can produce rarefaction regions in trapped particles. It is suggested that the 10-hour modulation of interplanetary Jovian electrons may be associated with the arrival at the dawn magnetopause of a rarefaction region each planetary rotation.

  1. Standing Alfven wave current system at Io - Voyager 1 observations

    NASA Astrophysics Data System (ADS)

    Acuna, M. H.; Neubauer, F. M.; Ness, N. F.

    1981-09-01

    The enigmatic control of the occurrence frequency of Jupiter's decametric emissions by the satellite Io has been explained theoretically on the basis of its strong electrodynamic interaction with the corotating Jovian magnetosphere leading to field-aligned currents connecting Io with the Jovian ionosphere. Direct measurements of the perturbation magnetic fields due to this current system were obtained by the Goddard Space Flight Center magnetic field experiment on Voyager 1 on March 5, 1979, when it passed within 20,500 km south of Io. An interpretation in the framework of Alfven waves radiated by Io leads to current estimates of 2.8 x 10 to the 6th A. A mass density of 7400-13,600 proton mass units/cu cm is derived, which compares very favorably with independent observations of the torus composition characterized by 7-9 proton mass units per electron for a local electron density of 1050-1500/cu cm. The power dissipated in the current system may be important for heating the Io heavy ion torus, inner magnetosphere, Jovian ionosphere, and possibly the ionosphere or even the interior of Io.

  2. Using the 11-year Solar Cycle to Predict the Heliosheath Environment at Voyager 1 and 2

    NASA Astrophysics Data System (ADS)

    Michael, A.; Opher, M.; Provornikova, E.; Richardson, J. D.; Toth, G.

    2015-12-01

    As Voyager 2 moves further into the heliosheath, the region of subsonic solar wind plasma in between the termination shock and the heliopause, it has observed an increase of the magnetic field strength to large values, all while maintaining magnetic flux conservation. Dr. Burlaga will present these observations in the 2015 AGU Fall meeting (abstract ID: 59200). The increase in magnetic field strength could be a signature of Voyager 2 approaching the heliopause or, possibly, due to solar cycle effects. In this work we investigate the role the 11-year solar cycle variations as well as magnetic dissipation effects have on the heliosheath environments observed at Voyager 1 and 2 using a global 3D magnetohydrodynamic model of the heliosphere. We use time and latitude-dependent solar wind velocity and density inferred from SOHO/SWAN and IPS data and solar cycle variations of the magnetic field derived from 27-day averages of the field magnitude average of the magnetic field at 1 AU from the OMNI database as presented in Michael et al. (2015). Since the model has already accurately matched the flows and magnetic field strength at Voyager 2 until 93 AU, we extend the boundary conditions to model the heliosheath up until Voyager 2 reaches the heliopause. This work will help clarify if the magnetic field observed at Voyager 2 should increase or decrease due to the solar cycle. We describe the solar magnetic field both as a dipole, with the magnetic and rotational axes aligned, and as a monopole, with magnetic field aligned with the interstellar medium to reduce numerical reconnection within the heliosheath, due to the removal of the heliospheric surrent sheet, and at the solar wind - interstellar medium interface. A comparison of the models allows for a crude estimation of the role that magnetic dissipation plays in the system and whether it allows for a better understanding of the Voyager 2 location in the heliosheath.

  3. Brave New Media World: Science Communication Voyages through the Global Seas

    NASA Astrophysics Data System (ADS)

    Clark, C. L.; Reisewitz, A.

    2010-12-01

    By leveraging online tools, such as blogs, Twitter, Facebook, Google Earth, flickr, web-based discussion boards, and a bi-monthly electronic magazine for the non-scientist, Scripps Institution of Oceanography is taking science communications out of the static webpage to create interactive journeys that spark social dialogue and helped raise awareness of science-based research on global marine environmental issues. Several new initiatives are being chronicled through popular blogs and expedition web sites as researchers share interesting scientific facts and unusual findings in near real-time.

  4. Voyaging on the Seas of Spirit: An Ongoing Journey towards Understanding Disability and Humanity

    ERIC Educational Resources Information Center

    Stienstra, Deborah; Ashcroft, Terri

    2010-01-01

    In an important article in "Disability & Society" Hughes argued that ontology is becoming a "live issue" in disability studies. Different sources, including non-western and aboriginal conceptions of disability and cosmology and the literature on philosophy, religion, palliative and healthcare, suggest that we are missing a critical aspect of…

  5. RADIAL VELOCITY ALONG THE VOYAGER 1 TRAJECTORY: THE EFFECT OF SOLAR CYCLE

    SciTech Connect

    Pogorelov, N. V.; Zank, G. P.; Borovikov, S. N.; Burlaga, L. F.; Decker, R. A.; Stone, E. C.

    2012-05-01

    As Voyager 1 and Voyager 2 are approaching the heliopause (HP)-the boundary between the solar wind (SW) and the local interstellar medium (LISM)-we expect new, unknown features of the heliospheric interface to be revealed. A seeming puzzle reported recently by Krimigis et al. concerns the unusually low, even negative, radial velocity components derived from the energetic ion distribution. Steady-state plasma models of the inner heliosheath (IHS) show that the radial velocity should not be equal to zero even at the surface of the HP. Here we demonstrate that the velocity distributions observed by Voyager 1 are consistent with time-dependent simulations of the SW-LISM interaction. In this Letter, we analyze the results from a numerical model of the large-scale heliosphere that includes solar cycle effects. Our simulations show that prolonged periods of low to negative radial velocity can exist in the IHS at substantial distances from the HP. It is also shown that Voyager 1 was more likely to observe such regions than Voyager 2.

  6. Propagation of transient shocks from 1 AU to the Voyagers during 2012-2015

    NASA Astrophysics Data System (ADS)

    Fermo, R. L.; Pogorelov, N. V.; Burlaga, L. F.

    2015-12-01

    The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression and rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. Starting from OMNI data at 1 AU, we present numerical simulations of such shocks in 2012, when Voyager 1 observed traveling shocks. We analyze the shock properties such as strength, propagation speed, and inter-shock separation by enhancing the resolution locally with adaptive mesh refinement. We compare these results with the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Lastly, we perform timing tests on the fully 3-D propagation of solar transients through the termination shock and heliopause, and determine if the transient features observed by Voyagers 1 and 2 beyond the heliopause might correspond to particular solar transients observed at 1 AU.

  7. Electron distributions in the inner Jovian magnetosphere: Voyager 1 observations

    NASA Technical Reports Server (NTRS)

    Ye, G.; Armstrong, T. P.

    1993-01-01

    Using several improvements in the analysis of the observations of the Low Energy Charged Particle (LECP) experiment on Voyager 1, electron phase space densities in the inner Jovian magnetosphere (5 - 10 R(sub J) were first calculated at constant first and second invariants (represented by mu and K, respectively), based on the LECP measurements. The calculated electron phase space density profiles show that in the inner Jovian magnetosphere there exist evident time and longitude variations, energetic electron injections, and present radial transport and distributed losses. To study the radial and pitch angle diffusions of Jovian electrons, we have calculated the phase space densities in the K-L space. It is found that the electron population in the inner Jovian magnetosphere seems to consist of two components: electrons radially diffusing from a main external source and electrons generated from local sources. The radially diffusing electrons have a relatively time stationary and isotropic distribution, while the locally created electrons mainly concentrate around the equatorial plane and have relatively lower energies, in comparison with the inward diffusing electrons. Consequently, the sources of precipitation losses to the ionosphere must be primarily electrons transported from outer sources, and the major precipitations occur in the inner magnetosphere (L less than 7.5 R(sub J). In the inner Jovian magnetosphere (L = 5 to approximately 10 R(sub J)) it is estimated that for electrons with magnetic moment mu = 300 MeV/G, the diffusion coefficient D is roughly 10(exp -8) to approximately 10(exp -6) R(exp 2)(sub J)/s, and the lifetime against the diffusion losses is of the order of 10(exp 4) to approximately 10(exp 6) s.

  8. Plasma observations near saturn: initial results from voyager 1.

    PubMed

    Bridge, H S; Belcher, J W; Lazarus, A J; Olbert, S; Sullivan, J D; Bagenal, F; Gazis, P R; Hartle, R E; Ogilvie, K W; Scudder, J D; Sittler, E C; Eviatar, A; Siscoe, G L; Goertz, C K; Vasyliunas, V M

    1981-04-10

    Extensive measurements of low-energy plasma electrons and positive ions were made during the Voyager 1 encounter with Saturn and its satellites. The magnetospheric plasma contains light and heavy ions, probably hydrogen and nitrogen or oxygen; at radial distances between 15 and 7 Saturn-radii (Rs) on the inbound trajectory, the plasma appears to corotate with a velocity within 20 percent of that expected for rigid corotation. The general morphology of Saturn's magnetosphere is well represented by a plasma sheet that extends from at least 5 to 17 Rs, is symmetrical with respect to Saturn's equatorial plane and rotation axis, and appears to be well ordered by the magnetic shell parameter L (which represents the equatorial distance of a magnetic field line measured in units of Rs). Within this general configuration, two distinct structures can be identified: a central plasma sheet observed from L = 5 to L = 8 in which the density decreases rapidly away from the equatorial plane, and a more extended structure from L = 7 to beyond 18 Rs in which the density profile is nearly flat for a distance +/- 1.8 Rs off the plane and falls rapidly thereafter. The encounter with Titan took place inside the magnetosphere. The data show a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan. Titan appears to be a significant source of ions for the outer magnetosphere. The locations of bow shock crossings observed inbound and outbound indicate that the shape of the Saturnian magnetosphere is similar to that of Earth and that the position of the stagnation point scales approximately as the inverse one-sixth power of the ram pressure.

  9. Voyager 1 in the foreshock, termination shock, and heliosheath.

    PubMed

    Decker, R B; Krimigis, S M; Roelof, E C; Hill, M E; Armstrong, T P; Gloeckler, G; Hamilton, D C; Lanzerotti, L J

    2005-09-23

    Voyager 1 (V1) began measuring precursor energetic ions and electrons from the heliospheric termination shock (TS) in July 2002. During the ensuing 2.5 years, average particle intensities rose as V1 penetrated deeper into the energetic particle foreshock of the TS. Throughout 2004, V1 observed even larger, fluctuating intensities of ions from 40 kiloelectron volts (keV) to >/=50 megaelectron volts per nucleon and of electrons from >26 keV to >/=350 keV. On day 350 of 2004 (2004/350), V1 observed an intensity spike of ions and electrons that was followed by a sustained factor of 10 increase at the lowest energies and lesser increases at higher energies, larger than any intensities since V1 was at 15 astronomical units in 1982. The estimated solar wind radial flow speed was positive (outward) at approximately +100 kilometers per second (km s(-1)) from 2004/352 until 2005/018, when the radial flows became predominantly negative (sunward) and fluctuated between approximately -50 and 0 km s(-1) until about 2005/110; they then became more positive, with recent values (2005/179) of approximately +50 km s(-1). The energetic proton spectrum averaged over the postshock period is apparently dominated by strongly heated interstellar pickup ions. We interpret these observations as evidence that V1 was crossed by the TS on 2004/351 (during a tracking gap) at 94.0 astronomical units, evidently as the shock was moving radially inward in response to decreasing solar wind ram pressure, and that V1 has remained in the heliosheath until at least mid-2005.

  10. EVIDENCE FOR A SHOCK IN INTERSTELLAR PLASMA: VOYAGER 1

    SciTech Connect

    Burlaga, L. F.; Ness, N. F.; Gurnett, D. A.; Kurth, W. S. E-mail: nfnudel@yahoo.com E-mail: william-kurth@uiowa.edu

    2013-11-20

    Voyager 1 (V1) observed electron plasma oscillations preceding a jump by a factor of 1.4 in the magnetic field intensity B near the end of 2012. The frequency of the electron plasma oscillations gives an electron density n{sub e}  = 0.05 cm{sup –3}, which implies that V1 was immersed in plasma from the interstellar medium. The last day on which plasma oscillations were observed is day 332, 2012, and the jump in the B was centered on day 335, 2012 after a data gap in the wave data. The close association between the electron plasma oscillations and the jump in B suggests a causal connection, such as that frequently observed between electron plasma oscillations and interplanetary shocks at 1 AU. Based on the observed parameters and the smooth profile of B(t), the jump in B appears to be associated with a weak, subcritical, laminar, low beta, quasi-perpendicular, resistive, collisionless shock. However, the width of the jump is of the order of 10{sup 4} times that expected for such a stationary shock at 1 AU. The large width of the jump in B might be the result of differences between the structure of shocks in the interstellar medium and the plasma near 1 AU. Alternatively, the subcritical resistive shock might have decayed during a few days after producing the plasma waves, leaving a broad profile in B(t) without significantly changing ambient parameters. Another possibility is that the jump in B is a pressure wave.

  11. COMPRESSIBLE 'TURBULENCE' OBSERVED IN THE HELIOSHEATH BY VOYAGER 2

    SciTech Connect

    Burlaga, L. F.; Ness, N. F. E-mail: nfnudel@yahoo.co

    2009-09-20

    This paper describes the multiscale structure of the compressible 'turbulence' observed in the high-resolution (48 s) observations of the magnetic field strength B made by Voyager 2 (V2) in the heliosheath behind the termination shock from 2007 DOY 245.0-300.8 and in a unipolar region from 2008 DOY 2.9-75.6. The magnetic field strength is highly variable on scales from 48 s to several hours in both intervals. The distributions of daily averages and 48 s averages of B are lognormal in the post-termination shock (TS) region and Gaussian in the unipolar region, respectively. The amplitudes of the fluctuations were greater in the post-TS region than in the unipolar region, at scales less than several hours. The multiscale structure of the increments of B is described by the q-Gaussian distribution of nonextensive statistical mechanics on all scales from 48 s to 3.4 hr in the unipolar region and from 48 s to 6.8 hr in the post-TS region, respectively. The amplitudes of the fluctuations of increments of B are larger in the post-TS region than in the unipolar region at all scales. The probability density functions of the increments of B are non-Gaussian at all scales in the unipolar region, but they are Gaussian at the largest scales in the post-TS region. Time series of the magnitude and direction of B show that the fluctuations are highly compressive. The small-scale fluctuations are a mixture of coherent structures (semi-deterministic structures) and random structures, which vary significantly from day to day. Several types of coherent structures were identified in both regions.

  12. Voyager 2 Color Image of Enceladus, Almost Full Disk

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This color Voyager 2 image mosaic shows the water-ice-covered surface of Enceladus, one of Saturn's icy moons. Enceladus' diameter of just 500 km would fit across the state of Arizona, yet despite its small size Enceladus exhibits one of the most interesting surfaces of all the icy satellites. Enceladus reflects about 90% of the incident sunlight (about like fresh-fallen snow), placing it among the most reflective objects in the Solar System. Several geologic terrains have superposed crater densities that span a factor of at least 500, thereby indicating huge differences in the ages of these terrains. It is possible that the high reflectivity of Enceladus' surface results from continuous deposition of icy particles from Saturn's E-ring, which in fact may originate from icy volcanoes on Enceladus' surface. Some terrains are dominated by sinuous mountain ridges from 1 to 2 km high (3300 to 6600 feet), whereas other terrains are scarred by linear cracks, some of which show evidence for possible sideways fault motion such as that of California's infamous San Andreas fault. Some terrains appear to have formed by separation of icy plates along cracks, and other terrains are exceedingly smooth at the resolution of this image. The implication carried by Enceladus' surface is that this tiny ice ball has been geologically active and perhaps partially liquid in its interior for much of its history. The heat engine that powers geologic activity here is thought to be elastic deformation caused by tides induced by Enceladus' orbital motion around Saturn and the motion of another moon, Dione.

  13. Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time

    NASA Astrophysics Data System (ADS)

    Shapiro Key, Joey; Yunes, Nico; Grimberg, Irene

    2015-01-01

    Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time is a gravitational wave astronomy planetarium show in production by a collaboration of scientists, filmmakers, and artisits from the Center for Gravitational Wave Astonomy (CGWA) at the University of Texas at Brownsville (UTB) and Montana State University (MSU). The project builds on the success of the interdisciplinary Celebrating Einstein collaboration. The artists and scientists who created the A Shout Across Time original film and the Black (W)hole immersive art installation for Celebrating Einstein are teaming with the Museum of the Rockies Taylor Planetarium staff and students to create a new full dome Digistar planetarium show that will be freely and widely distributed to planetaria in the US and abroad. The show uses images and animations filmed and collected for A Shout Across Time and for Black (W)hole as well as new images and animations and a new soundtrack composed and produced by the MSU School of Music to use the full capability of planetarium sound systems. The planetarium show will be narrated with ideas drawn from the Celebrating Einstein danced lecture on gravitational waves that the collaboration produced. The combination of products, resources, and team members assembled for this project allows us to create an original planetarium show for a fraction of the cost of a typical show. In addition, STEM education materials for G6-12 students and teachers will be provided to complement and support the show. This project is supported by the Texas Space Grant Consortium (TSGC), Montana Space Grant Consortium (MSGC), and the American Physical Society (APS).

  14. INTERSTELLAR MAGNETIC FIELDS OBSERVED BY VOYAGER 1 BEYOND THE HELIOPAUSE

    SciTech Connect

    Burlaga, L. F.; Ness, N. F. E-mail: nfnudel@yahoo.com

    2014-11-01

    Voyager 1 (V1) was beyond the heliopause between 2013.00 and 2014.41, where it was making in situ observations of the interstellar magnetic field (ISMF). The average azimuthal angle and elevation angle of the magnetic field B were (λ) = 292.°5 ± 1.°4 and (δ) = 22.°1 ± 1.°2, respectively. The angles λ and δ varied linearly at (1.°4 ± 0.°1) yr{sup –1} and (–1.°1 ± 0.°1) yr{sup –1}, respectively, suggesting that V1 was measuring the draped ISMF around the heliopause. The distributions of hourly averages of λ and δ were Gaussian distributions, with most probable values 292.°5 and 22.°1, and standard deviations (SDs) 1.°3 and 1.°1, respectively. The small SD indicates little or no turbulence transverse to B . An abrupt decrease in B from 0.50 nT on 2013/129.9 to 0.46 nT on 2013/130.6 was observed, possibly associated with a weak reverse shock or magnetoacoustic pressure wave following a burst of electron plasma oscillations. Between 2013/130.6 and 2013/365.3, (B) = 0.464 ± 0.009 nT, (λ) = 292.°6 ± 0.°8, and (δ) = 22.°1 ± 1.°1. The corresponding distribution of hourly averages of B was Gaussian with the most probable value 0.464 nT and σ = 0.009 nT. Since the uncertainty σ corresponds to the instrument and digitization noise, these observations provided an upper limit to the turbulence in the ISMF. The distributions of the hourly increments of B were Gaussian distributions with σ = 0.05 nT, 0.°4, and 0.°4, respectively, indicating that the V1 did not detect evidence of ''intermittent bursts'' of interstellar turbulence.

  15. Plasma observations near saturn: initial results from voyager 1.

    PubMed

    Bridge, H S; Belcher, J W; Lazarus, A J; Olbert, S; Sullivan, J D; Bagenal, F; Gazis, P R; Hartle, R E; Ogilvie, K W; Scudder, J D; Sittler, E C; Eviatar, A; Siscoe, G L; Goertz, C K; Vasyliunas, V M

    1981-04-10

    Extensive measurements of low-energy plasma electrons and positive ions were made during the Voyager 1 encounter with Saturn and its satellites. The magnetospheric plasma contains light and heavy ions, probably hydrogen and nitrogen or oxygen; at radial distances between 15 and 7 Saturn-radii (Rs) on the inbound trajectory, the plasma appears to corotate with a velocity within 20 percent of that expected for rigid corotation. The general morphology of Saturn's magnetosphere is well represented by a plasma sheet that extends from at least 5 to 17 Rs, is symmetrical with respect to Saturn's equatorial plane and rotation axis, and appears to be well ordered by the magnetic shell parameter L (which represents the equatorial distance of a magnetic field line measured in units of Rs). Within this general configuration, two distinct structures can be identified: a central plasma sheet observed from L = 5 to L = 8 in which the density decreases rapidly away from the equatorial plane, and a more extended structure from L = 7 to beyond 18 Rs in which the density profile is nearly flat for a distance +/- 1.8 Rs off the plane and falls rapidly thereafter. The encounter with Titan took place inside the magnetosphere. The data show a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan. Titan appears to be a significant source of ions for the outer magnetosphere. The locations of bow shock crossings observed inbound and outbound indicate that the shape of the Saturnian magnetosphere is similar to that of Earth and that the position of the stagnation point scales approximately as the inverse one-sixth power of the ram pressure. PMID:17783833

  16. Radial evolution of the solar wind from IMP 8 to Voyager 2

    NASA Technical Reports Server (NTRS)

    Richardson, John D.; Paularena, Karolen I.; Lazarus, Alan J.; Belcher, John W.

    1995-01-01

    Voyager 2 and Interplanetary Monitoring Platform (IMP) 8 data from 1977 through 1994 are presented and compared. Radial velocity and temperature structures remain intact over the distance from 1 to 43 AU, but density structures do not. Temperature and velocity changes are correlated and nearly in phase at 1 AU, but in the outer heliosphere temperature changes lead velocity changes by tens of days. Solar cycle variations are detected by both spacecraft, with minima in flux density and dynamic pressure near solar maxima. Differences between Voyager 2 and IMP 8 observations near the solar minimum in 1986-1987 are attributed to latitudinal gradients in solar wind properties. Solar rotation variations are often present even at 40 AU. The Voyager 2 temperature profile is best fit with a R(exp -0.49 +/- 0.01) decrease, much less steep than an adiabatic profile.

  17. Jupiter's Cloud Distribution Between the Voyager 1 and 2 Encounters: Results from 5-Micrometer Imaging.

    PubMed

    Terrile, R J; Capps, R W; Becklin, E E; Cruikshank, D P

    1979-11-23

    As part of a continuing effort of ground-based support for Voyager target selection, infrared images in the 5-micrometer wavelength region were acquired in preparation for the Voyager 2 flyby of Jupiter. Observations were made during May 1979 from the Palomar 5-meter telescope and the new 3-meter NASA Infrared Telescope Facility at Mauna Kea and are compared to previous observations. Variations seen in the 5-micrometer flux distribution suggest global patterns of clouding over of some Jovian belts and clearing ofothers. These data were used to predict the Jovian cloud distribution at the time of the Voyager 2 encounter in order to target the imaging and infrared experiments to areas free of high obscuring clouds.

  18. Re-Analysis of Galileo Cassini & Voyager EUV Observations of the Io Plasma Torus

    NASA Astrophysics Data System (ADS)

    Nerney, E. G.

    2015-12-01

    We present a survey of conditions observed in the Io plasma torus from the Voyager flyby, throughout the Galileo mission (1995 to 2003), & the Cassini flyby of Jupiter (fall 2000 to spring 2001). On the Cassini spacecraft the UVIS instrument made extensive observations of the spatial and temporal variations of torus emissions (Steffl et al. 2004, 2006). We re-analyze the Voyager, Galileo & Cassini EUV observations of torus emissions with a physical chemistry model based on Delamere et al. (2004) to derive modest spatial and temporal variations in torus model parameters (transport time, neutral source, population of hot electrons, ratio of neutral oxygen to sulfur atoms in the source). Torus plasma conditions (Temperature and mixing ratios of the different model species) derived from these emissions are also compared with in situ measurements by the Voyager PLS instruments and ground-based observations of torus emissions.

  19. Jupiter's Cloud Distribution Between the Voyager 1 and 2 Encounters: Results from 5-Micrometer Imaging.

    PubMed

    Terrile, R J; Capps, R W; Becklin, E E; Cruikshank, D P

    1979-11-23

    As part of a continuing effort of ground-based support for Voyager target selection, infrared images in the 5-micrometer wavelength region were acquired in preparation for the Voyager 2 flyby of Jupiter. Observations were made during May 1979 from the Palomar 5-meter telescope and the new 3-meter NASA Infrared Telescope Facility at Mauna Kea and are compared to previous observations. Variations seen in the 5-micrometer flux distribution suggest global patterns of clouding over of some Jovian belts and clearing ofothers. These data were used to predict the Jovian cloud distribution at the time of the Voyager 2 encounter in order to target the imaging and infrared experiments to areas free of high obscuring clouds. PMID:17733922

  20. Ray tracing of Jovian decametric radiation from Southern and Northern Hemisphere sources - Comparison with Voyager observations

    NASA Technical Reports Server (NTRS)

    Menietti, J. Douglas; Green, James L.; Six, N. Frank; Gulkis, S.

    1987-01-01

    The Voyager 1 and 2 Planetary Radio Astronomy observations of Io-dependent decametric (DAM) radiation originating from the Southern Hemisphere of Jupiter were compared with the results of three-dimensional model ray tracing calculations of the DAM radiation. The ray trajectories for sources located at constant sub-Io longitudes of 260 and 300 deg were computed for both the Northern and the Southern Jovian Hemisphere sources. The model results of wave propagation agree with the Voyager observations obtained with Io located at 260 and 300 deg in Jovian system III longitude. The agreement between the Voyager observations and the model ray tracings allows identification of the origin of several of the emission components.

  1. SkyServer Voyages Website - Using Big Data to Explore Astronomy Concepts in Formal Education Settings

    NASA Astrophysics Data System (ADS)

    Meredith, Kate K.; Masters, Karen; Raddick, Jordan; Lundgren, Britt

    2015-08-01

    The Sloan Digital Sky Survey (SDSS) web interface “SkyServer” has long included online educational materials designed to help students and the public discover the fundamentals of modern astronomy using real observations from the SDSS database. The newly launched SDSS Voyages website updates and expands these activities to reflect new data from subsequent generations of the survey, advances in web technology, and evolving practices in science education. Voyages provides access to quality astronomy, astrophysics, and engineering materials to educators seeking an inquiry approach to fundamental concepts. During this session we will provide an overview of the design and development of Skyserver Voyages and discuss ways to apply this resource at K-12 and university levels.

  2. [Signs of chronic cardiac insufficiency in merchant marine sailors on long voyages].

    PubMed

    Kamalutdinov, S R; Popov, V V; Ivanova, T N

    2012-01-01

    Incidence of symptoms and clinical signs of chronic cardiac insufficiency (CCI) was studied in sailors in the Northern basin. Their variations were tracked and risk factors of that are most likely to provoke cardiovascuar diseases (CVDs) during 6-mos. voyages were elicted. Examined were 225 sailors of 10 sister large-capacity vessels belonging to Russian shipowners. Clinical condition and the cardiovascular function of the sailors were assessed on months 1, 3 and 6 using physical methods and ECG, provocative tests and clinical condition scoring scale. Physical activity was evaluated. Incidence of CCI symptoms and clinical signs in sailors was significantly in excess of the all-Russian value. Clinical condition of sailors with CCI symptoms and clinical signs was noted to grow worse by the end of voyage. Factors contributing to CCI development and aggravation during long voyages were identified. PMID:23074954

  3. Solar Cycle Dependence of the Solar Wind Dynamics: Pioneer, Voyager, and Ulysses from 1 to 5 AU

    NASA Technical Reports Server (NTRS)

    Gonzalez-Esparza, J. A.; Smith, E. J.

    1996-01-01

    Significant differences between Pioneer and Voyager observations were found in solar wind structure between 1 to 6 AU. These disagreements were attributed to temporal effects related to the solar cycle, but no unifying study of Pioneer-Voyager observations was performed.

  4. The Voyager Universal Literacy System: Results from a Study of Kindergarten Students in Inner-City Schools

    ERIC Educational Resources Information Center

    Frechtling, Joy A.; Zhang, Xiaodong; Silverstein, Gary

    2006-01-01

    The evaluation of the Voyager Universal Literacy System[R] was designed to provide a rigorous assessment of the effectiveness of the program with beginning readers. Using a quasi-experimental design, researchers conducted a systematic evaluation of changes in 398 kindergarten students' command of early reading skills in 4 Voyager and 4 comparison…

  5. The Plasma Depletion Layer Beyond the Heliopause: Evidence, Implications, and Predictions for Voyager 2

    NASA Astrophysics Data System (ADS)

    Cairns, I. H.; Fuselier, S. A.

    2015-12-01

    A plasma depletion layer (PDL) is predicted beyond the heliopause, analogous to the PDLs observed sunwards of the magnetopauses of Earth, Mercury, Jupiter, and Saturn. The physics is that draping of interstellar (ISM) magnetic field lines over the heliopause should increase the magnetic field strength (and so the perpendicular ion temperature), cause density depletions by allowing plasma ions (and electrons) with large parallel temperatures to escape along the field, and increase the perpendicular to parallel temperature anisotropy until limited by wave instabilities. It is argued that published Voyager 1 magnetometer and plasma wave data beyond the heliopause provide strong evidence for the magnetic field amplification (by ≈ 30%) and density depletion (by ≈ 50%) expected for the PDL. The predicted reduction in parallel temperature is ≈ 50%. Using the ISM magnetic field direction obtained from the centroid of the IBEX Ribbon, the orientation of the PDL and the associated locations on the heliopause of the points of maximum magnetic field draping and maximum total pressure are predicted. It is observed that the IBEX Ribbon overlies the former while the latter lies within the ridge of maximum non-Ribbon ENA flux. The PDL should be strongest along the ISM field line passing through these points and the nominal Sun-ISM velocity vector. It is predicted that Voyager 2 lies within 5 degrees (≈ 10 AU) of the strong PDL region while Voyager 1 is over 15 degrees (≈ 35 AU) away. Thus Voyager 2 should observe a much stronger PDL (stronger magnetic field amplification, density depletions, and reductions in parallel temperature) than Voyager 1. Finally, the reduced cosmic ray fluxes observed near 90 degree pitchangle by Voyager 1 beyond the heliopause may be explained qualitatively in terms of magnetic focusing as cosmic rays propagate away from the stronger field regions of the PDL and magnetic draping region on the heliopause, assuming isotropic cosmic rays at the

  6. Infrared images of jupiter at 5-micrometer wavelength during the voyager 1 encounter.

    PubMed

    Terrile, R J; Capps, R W; Backman, D E; Becklin, E E; Cruikshank, D P; Beichman, C A; Brown, R H; Westphal, J A

    1979-06-01

    A coordinated program to observe Jupiter at high spatial resolution in the 5-micrometer wavelength region was undertaken to support Voyager 1 imaging and infrared radiation experiment targeting. Jupiter was observed over a 5-month period from Palomar and Mauna Kea observatories. The frequency of observations allowed the selection of interesting areas for closer Voyager examination and also provided good short-term monitoring of variations in cloud morphology. Significant global changes in the 5-micrometer distribution are seen over this time period. PMID:17800441

  7. A model of Saturn's seasonal stratosphere at the time of the Voyager encounters

    NASA Technical Reports Server (NTRS)

    Carlson, B. E.; Caldwell, J.; Cess, R. D.

    1980-01-01

    A polar-equatorial climate model by Cess and Cladwell (1979) is extended to all latitudes of Saturn. Modifications for solar absorption within the stratosphere are made in the extension to intermediate latitudes. The latitudinally and temporally variable effects of sunlight absorption by the rings of Saturn are included in the model. Temperature-latitude profiles for several levels within the Saturn stratosphere are presented for January 1981, which should be directly comparable with Saturn Voyager observations in November 1980 and August 1981. Temperature-pressure profiles for latitudes +30 degrees and -25 degrees are provided, which correspond to the planned points at which radio equipment aboard Voyager II will produce occultation observations.

  8. Uranian ring orbits from earth-based and Voyager occultation observations

    NASA Astrophysics Data System (ADS)

    French, R. G.; Elliot, J. L.; French, L. M.; Kangas, J. A.; Meech, K. J.; Ressler, M. E.; Buie, M. W.; Frogel, J. A.; Holberg, J. B.; Fuensalida, J. J.; Joy, M.

    1988-02-01

    The authors have combined an enhanced Earth-based occultation data set and Voyager occultation observations to determine a new solution for the ring orbital elements and the direction of the planetary pole. They describe the new ground-based observations and the Voyager data used for this analysis. They discuss the new orbit solution and a search for resonances associated with the γ and δ rings, which are not well matched by simple elliptical orbits. Then the authors discuss the new solution and investigate the suspected association of resonances between satellites 1986U7 and 1986U8 and some of the rings.

  9. Gain, phase and frequency stability of DSS-42 and DSS-43 vor Voyage Uranus encounter

    NASA Technical Reports Server (NTRS)

    Cha, A. G.; Levy, R.

    1986-01-01

    Theoretically rigorous definitions are derived of such parameters as RF signal path length, phase delay, and phase/frequency stability in a Cassegrainian antenna applicable to a narrow bandwidth channel, as well as algorithms for evaluating these parameters. This work was performed in support of the Voyager spacecraft encounter with Uranus in January 1986. The information was needed to provide Voyager/Uranus radio science researchers with a rotational basis for deciding the best strategy to operate the three antennas involved during the crucial 5-hour occultation period of the encounter. Such recommendations are made at the end of the article.

  10. THICKNESS OF THE HELIOSHEATH, RETURN OF THE PICK-UP IONS, AND VOYAGER 1'S CROSSING THE HELIOPAUSE

    SciTech Connect

    Hsieh, K. C.; Giacalone, J.; Kota, J.; Czechowski, A.; Grzedzielski, S.; Hilchenbach, M.

    2010-08-01

    Using results of remote sensing by energetic neutral atoms from IBEX, SOHO/HSTOF, and Cassini/INCA, in situ measurements of {approx}40-4000 keV protons in the heliosheath (HS) from Low Energy Charged Particle on Voyager 1 and Voyager 2, and outputs from numerical modeling of the termination shock, we estimate L, the characteristic thickness of the HS in the 'upwind' direction ({+-}45{sup 0} in ecliptic longitude of the Nose at {lambda} = 255{sup 0}). A simple steady-state, internally consistent model gives L = 21 {+-} 6 AU for Voyager 1, L = 28 {+-} 8 AU for Voyager 2, and L = 25 {+-} 8 AU assuming that the same L value is valid for both spacecraft. We recognize that this is a very coarse cut at a very dynamic region of the heliosphere; but if the lower value L = 21 AU applies, one could expect Voyager 1 to cross the heliopause as early as late 2010.

  11. The deepwater demersal ichthyofauna of the western Coral Sea.

    PubMed

    Last, Peter R; Pogonoski, John J; Gledhill, Daniel C; White, William T; Walker, Chris J

    2014-01-01

    The highly diverse deepwater demersal ichthyofauna of the western Coral Sea was first systematically surveyed in two exploratory voyages in 1985 and 1986, and these fish assemblages have not been investigated at the same level since. Only recently have catch data and specimens, obtained from these first voyages almost 3 decades ago, been rigorously investigated and analysed. Some 393 species of fishes from 125 families were collected during the 1985 voyage which surveyed the northeastern Australian continental margin, and the Saumarez and Queensland Plateaus. A checklist of the species caught is provided. Levels of endemicity of deepwater fishes in the western Coral Sea are very high with about 50% of well-studied groups, such as sharks and rays, confined to this relatively small geographic region. A very high proportion of species caught during this voyage were either undescribed (78 species or 20%) or new Australian records (96 species or 24%) at the time of the survey. Another 68 species (17%) are the subject of further taxonomic investigation or are currently undergoing formal description. The fauna exhibits some intraregional differences in structure. Biogeographically informative fishes such as skates appear to be cryptically partitioned within the region, differing in composition to other Australian regions and those of French territories to the east. Strong depth-related partitioning of the fauna is also evident, and its structure follows zonation patterns observed across the wider Australian region. Given the high level of micro-endemicity and regional uniqueness of the fauna, there is a compelling argument for the existence of a faunal gyre in the Coral Sea.  New gap-filling surveys are needed to better define the structure of this fauna and determine its distribution. PMID:25543931

  12. Infrared observations of the saturnian system from voyager 1.

    PubMed

    Hanel, R; Conrath, B; Flasar, F M; Kunde, V; Maguire, W; Pearl, J; Pirraglia, J; Samuelson, R; Herath, L; Allison, M; Cruikshank, D; Gautier, D; Gierasch, P; Horn, L; Koppany, R; Ponnamperuma, C

    1981-04-10

    During the passage of Voyager 1 through the Saturn system, the infrared instrument acquired spectral and radiometric data on Saturn, the rings, and Titan and other satellites. Infrared spectra of Saturn indicate the presence of H(2), CH(4), NH(3), PH(3), C(2)H(2), C(2)H(6), and possibly C(3)H(4) and C(3)H(8). A hydrogen mole fraction of 0.94 is inferred with an uncertainty of a few percent, implying a depletion of helium in the atmosphere of Saturn relative to that of Jupiter. The atmospheric thermal structure of Saturn shows hemisphere asymmetries that are consistent with a response to the seasonally varying insolation. Extensive small-scale latitudinal structure is also observed. On Titan, positive identifications of infrared spectral features are made for CH(4), C(2)H(2), C(2)H(4), C(2)H(6), and HCN; tentative identifications are made for C(3)H(4) and C(3)H(8). The infrared continuum opacity on Titan appears to be quite small between 500 and 600 cm(-1), implying that the solid surface is a major contributor to the observed emission over this spectral range; between 500 and 200 cm(-1) theopacity increases with decreasing wave number, attaining an optical thickness in excess of 2 at 200 cm(-1). Temperatures near the 1-millibar level are independent of longitude and local time but show a decrease of approximately 20 K between the equator and north pole, which suggests a seasonally dependent cyclostrophic zonal flow in the stratosphere of approximately 100 meters per second. Measurements of the C ring of Saturn yield a temperature of 85 +/- 1 K and an infrared optical depth of 0.09 +/- 0.01. Radiometer observations of sunlight transmitted through the ring system indicate an optical depth of 10(-1.3 +/-0.3) for the Cassini division. A phase integral of 1.02 +/- 0.06 is inferred for Rhea, which agrees with values for other icy bodies in the solar system. Rhea eclipse observations indicate the presence of surface materials with both high and low thermal inertias, the

  13. Hot plasma environment at jupiter: voyager 2 results.

    PubMed

    Krimigis, S M; Armstrong, T P; Axford, W I; Bostrom, C O; Fan, C Y; Gloeckler, G; Lanzerotti, L J; Keath, E P; Zwickl, R D; Carbary, J F; Hamilton, D C

    1979-11-23

    Measurements of the hot (electron and ion energies >/=20 and >/= 28 kiloelectron volts, respectively) plasma environment at Jupiter by the low-energy charged particle (LECP) instrument on Voyager 2 have revealed several new and unusual aspects of the Jovian magnetosphere. The magnetosphere is populated from its outer edge into a distance of at least approximately 30 Jupiter radii (R(J)) by a hot (3 x 10(8) to 5 x 10(8) K) multicomponent plasma consisting primarily of hydrogen, oxygen, and sulfur ions. Outside approximately 30 R(J) the hot plasma exhibits ion densities from approximately 10(-1) to approximately 10(-6) per cubic centimeter and energy densities from approximately 10(-8) to 10(-13) erg per cubic centimeter, suggesting a high beta plasma throughout the region. The plasma is flowing in the corotation direction to the edge of the magnetosphere on the dayside, where it is confined by solar wind pressure, and to a distance of approximately 140 to 160 R(J) on the nightside at approximately 0300 local time. Beyond approximately 150 R(J) the hot plasma flow changes into a "magnetospheric wind" blowing away from Jupiter at an angle of approximately 20 degrees west of the sun-Jupiter line, characterized by a temperature of approximately 3 x 10(8) K (26 kiloelectron volts), velocities ranging from approximately 300 to > 1000 kilometers per second, and composition similar to that observed in the inner magnetosphere. The radial profiles of the ratios of oxygen to helium and sulfur to helium (

  14. Christopher Columbus and the Great Voyage of Discovery. With a Message from President George Bush. Picture-book Biography Series, Volume 1.

    ERIC Educational Resources Information Center

    Weisman, JoAnne B.; Deitch, Kenneth M.

    An illustrated story for young children features Christopher Columbus's first voyage to the Americas in 1492. The story begins with Columbus's youth in Genoa, Italy, follows him to Portugal and then to Spain, where he finally received backing for a voyage west to reach the East Indies. The preparations for the voyage and the trip itself are…

  15. 46 CFR 185.220 - Records of a voyage resulting in a marine casualty.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... voyage records maintained by the vessel, including rough and smooth deck and engine room logs, bell books..., records of draft, aids to mariners, night order books, radiograms sent and received, radio logs, crew and passenger lists and counts, articles of shipment, official logs, and other material that might be...

  16. The Voyage of the Beagle: Field Work Lessons from Charles Darwin.

    ERIC Educational Resources Information Center

    Smith, Louis M.

    1987-01-01

    Analyzes Charles Darwin's letters to his family during his voyage on H.M.S. Beagle. Relates the information to the development of Darwin's professional identity and the degree to which the concepts, field methods, and research methods revealed in Darwin's personal correspondence are useful to students of educational administration. (MD)

  17. Voyager observations of the interaction of the heliosphere with the interstellar medium.

    PubMed

    Richardson, John D

    2013-05-01

    This paper provides a brief review and update on the Voyager observations of the interaction of the heliosphere with the interstellar medium. Voyager has found many surprises: (1) a new energetic particle component which is accelerated at the termination shock (TS) and leaks into the outer heliosphere forming a foreshock region; (2) a termination shock which is modulated by energetic particles and which transfers most of the solar wind flow energy to the pickup ions (not the thermal ions); (3) the heliosphere is asymmetric; (4) the TS does not accelerate anomalous cosmic rays at the Voyager locations; and (5) the plasma flow in the Voyagers 1 (V1) and 2 (V2) directions are very different. At V1 the flow was small after the TS and has recently slowed to near zero, whereas at V2 the speed has remained constant while the flow direction has turned tailward. V1 may have entered an extended boundary region in front of the heliopause (HP) in 2010 in which the plasma flow speeds are near zero.

  18. Voyager Universal Literacy System[R]. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2007

    2007-01-01

    The "Voyager Universal Literacy System"[R] is a core reading program designed to help students learn to read at or above grade level by the end of the third grade. This program uses strategies such as individual reading instruction, higher-level comprehension activities, problem solving, and writing. Students are also exposed to computer-based…

  19. With Community Colleges' Help, Voyager Program Expands Learning Opportunities for Children.

    ERIC Educational Resources Information Center

    Bumphus, Walter

    1998-01-01

    Describes the Voyager Program, a national educational initiative supporting elementary schools and teachers by providing essential supplies and a research-based curriculum. Reviews the role of selected community colleges in providing support for summer and after-school programs. (JDI)

  20. Worlds Apart: Context, Voyages and Encounters in the Age of Exploration. Updated Edition.

    ERIC Educational Resources Information Center

    Roelofs, Anna; Millstone, David

    This curriculum unit offers students the opportunity to become researchers of history. The curriculum is organized among three sections: (1) "Context," students are introduced to early seagoing peoples, their ideas and technologies, and to related ideas from Renaissance Europe; (2) "Voyages," students conduct individual research projects about the…

  1. 46 CFR 90.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... a protectorate or mandate, whose international relations are the responsibility of a contracting... 46 Shipping 4 2011-10-01 2011-10-01 false Application to vessels on an international voyage. 90.05... MISCELLANEOUS VESSELS GENERAL PROVISIONS Application § 90.05-10 Application to vessels on an...

  2. New local interstellar spectra for protons, helium and carbon derived from PAMELA and Voyager 1 observations

    NASA Astrophysics Data System (ADS)

    Bisschoff, D.; Potgieter, M. S.

    2016-02-01

    With the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere, the comparison of computed galactic spectra with experimental data at lower energies is finally possible. Spectra for specifically protons, helium and carbon nuclei, computed by galactic propagation models, can now be compared with observations at low energies from Voyager 1 and at high energies from the PAMELA space detector at Earth. We set out to reproduce the Voyager 1 observations in the energy range of 6 MeV/nuc to 60 MeV/nuc, and the PAMELA spectrum above 50 GeV/nuc, using the GALPROP code, similarly to our previous study for Voyager 1 electrons. By varying the galactic diffusion parameters in the GALPROP plain diffusion model, specifically the rigidity dependence of spatial diffusion, and then including reacceleration, we compute spectra simultaneously for galactic protons, helium and carbon. We present new local interstellar spectra, with expressions for the energy range of 3 MeV/nuc to 100 GeV/nuc, which should be of value for solar modulation modeling.

  3. Helios-Voyager cooperation for the investigation of the interplanetary space

    NASA Technical Reports Server (NTRS)

    Porsche, H.; Kehr, J.

    1978-01-01

    The planning of a joint mission involving the two Helios spacecraft and the two Voyager spacecraft is reported. During late fall 1977 the position of the four spacecraft facilitated correlation measurements as part of an investigation of interplanetary space in the vicinity of the earth. The spacecraft and their orbits are described, and the benefits that could result from future joint missions are considered.

  4. Voyager 2 at its farthest goal: Neptune - Icy worlds of wonder

    NASA Astrophysics Data System (ADS)

    Fischer, Daniel

    1989-10-01

    Findings about the Neptune system made by Voyager 2 are reviewed. The dynamic nature of Neptune's atmosphere, the orientation of its magnetosphere, and the nature of its rings are addressed. The surfaces of Neptune's moons are described, emphasizing Triton and its volcanoes.

  5. The Three Voyages of Edmond Halley in the Paramore: 1698-1701

    NASA Astrophysics Data System (ADS)

    Agnew, Duncan Carr

    On Thursday, October 20, 1698, a three-masted ship, captained by Edmond Halley with orders “to improve the knowledge of the Longitude and variations of the Compasse,” which he was to observe “with all the accuracy you can,” set sail from Deptford, England, on the first leg of the first voyage ever commissioned for strictly scientific purposes. Halley is now best known as an astronomer and for the comet that bears his name. However, his interests ranged over so many specialties that he is better described now by the 17th century title of “natural philosopher.” Among his various areas of study, the study of the earth took a major place, as shown by his many papers on the trade winds, the tides, and especially the magnetic field. This last interest led him to propose to the Royal Society that he make a voyage around the world “to discover what may be learnt … [of] the variations of the Magneticall Needle.” This ambitious undertaking was later scaled down to cover only the Atlantic Ocean, Halley made two voyages from 1698 to 1700, at one point reaching 52°S in his 52-foot vessel. As a tailpiece he made a third voyage in the summer and fall of 1701 to study the tides and tidal currents of the English Channel.

  6. 46 CFR 90.05-10 - Application to vessels on an international voyage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Application to vessels on an international voyage. 90.05... MISCELLANEOUS VESSELS GENERAL PROVISIONS Application § 90.05-10 Application to vessels on an international... section, the regulations in this subchapter that apply to a vessel on an “international voyage” apply to...

  7. Voyager radio science observations of neptune and triton.

    PubMed

    Tyler, G L; Sweetnam, D N; Anderson, J D; Borutzki, S E; Campbell, J K; Eshleman, V R; Gresh, D L; Gurrola, E M; Hinson, D P; Kawashima, N; Kursinski, E R; Levy, G S; Lindal, G F; Lyons, J R; Marouf, E A; Rosen, P A; Simpson, R A; Wood, G E

    1989-12-15

    The Voyager 2 encounter with the Neptune system included radio science investigations of the masses and densities of Neptune and Triton, the low-order gravitational harmonics of Neptune, the vertical structures of the atmospheres and ionospheres of Neptune and Triton, the composition of the atmosphere of Neptune, and characteristics of ring material. Demanding experimental requirements were met successfully, and study of the large store of collected data has begun. The initial search of the data revealed no detectable effects of ring material with optical depth tau [unknown] 0.01. Preliminary representative results include the following: 1.0243 x 10(26) and 2.141 x 10(22) kilograms for the masses of Neptune and Triton; 1640 and 2054 kilograms per cubic meter for their respective densities; 1355 +/- 7 kilometers, provisionally, for the radius of Triton; and J(2) = 3411 +/- 10(x 10(-6)) and J(4) = -26(+12)(-20)(x10(-6)) for Neptune's gravity field (J>(2) and J(4) are harmonic coefficients of the gravity field). The equatorial and polar radii of Neptune are 24,764 +/- 20 and 24,340 +/- 30 kllometers, respectively, at the 10(5)-pascal (1 bar) pressure level. Neptune's atmosphere was probed to a pressure level of about 5 x 10(5) pascals, and effects of a methane cloud region and probable ammonia absorption below the cloud are evident in the data. Results for the mixing ratios of helium and ammonia are still being investigated; the methane abundance below the clouds is at least 1 percent by volume. Derived temperature-pressure profiles to 1.2 x 10(5) pascals and 78 kelvins (K) show a lapse rate corresponding to "frozen" equilibrium of the para- and ortho-hydrogen states. Neptune's ionosphere exhibits an extended topside at a temperature of 950 +/- 160 K if H(+) is the dominant ion, and narrow ionization layers of the type previously seen at the other three giant planets. Triton has a dense ionosphere with a peak electron concentration of 46 x 10(9) per cubic meter at an

  8. Voyager radio science observations of neptune and triton.

    PubMed

    Tyler, G L; Sweetnam, D N; Anderson, J D; Borutzki, S E; Campbell, J K; Eshleman, V R; Gresh, D L; Gurrola, E M; Hinson, D P; Kawashima, N; Kursinski, E R; Levy, G S; Lindal, G F; Lyons, J R; Marouf, E A; Rosen, P A; Simpson, R A; Wood, G E

    1989-12-15

    The Voyager 2 encounter with the Neptune system included radio science investigations of the masses and densities of Neptune and Triton, the low-order gravitational harmonics of Neptune, the vertical structures of the atmospheres and ionospheres of Neptune and Triton, the composition of the atmosphere of Neptune, and characteristics of ring material. Demanding experimental requirements were met successfully, and study of the large store of collected data has begun. The initial search of the data revealed no detectable effects of ring material with optical depth tau [unknown] 0.01. Preliminary representative results include the following: 1.0243 x 10(26) and 2.141 x 10(22) kilograms for the masses of Neptune and Triton; 1640 and 2054 kilograms per cubic meter for their respective densities; 1355 +/- 7 kilometers, provisionally, for the radius of Triton; and J(2) = 3411 +/- 10(x 10(-6)) and J(4) = -26(+12)(-20)(x10(-6)) for Neptune's gravity field (J>(2) and J(4) are harmonic coefficients of the gravity field). The equatorial and polar radii of Neptune are 24,764 +/- 20 and 24,340 +/- 30 kllometers, respectively, at the 10(5)-pascal (1 bar) pressure level. Neptune's atmosphere was probed to a pressure level of about 5 x 10(5) pascals, and effects of a methane cloud region and probable ammonia absorption below the cloud are evident in the data. Results for the mixing ratios of helium and ammonia are still being investigated; the methane abundance below the clouds is at least 1 percent by volume. Derived temperature-pressure profiles to 1.2 x 10(5) pascals and 78 kelvins (K) show a lapse rate corresponding to "frozen" equilibrium of the para- and ortho-hydrogen states. Neptune's ionosphere exhibits an extended topside at a temperature of 950 +/- 160 K if H(+) is the dominant ion, and narrow ionization layers of the type previously seen at the other three giant planets. Triton has a dense ionosphere with a peak electron concentration of 46 x 10(9) per cubic meter at an

  9. Titan's atmospheric composition: from Voyager to Cassini and beyond

    NASA Astrophysics Data System (ADS)

    Coustenis, A.

    2007-12-01

    Titan's atmosphere was revealed by the Voyager missions in the 80s. The trace composition was in particular inferred from infrared spectra by the V1/IRIS Spectrometer. ISO gave us an opportunity to further explore this exciting milieu in 1997 (Coustenis et al., 1998; 2003) and brought the discovery of new molecules : H2O and C6H6. Our understanding of Titan's atmospheric chemical composition has recently been enhanced by the data returned by the Cassini instruments. Spectra recorded by the Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft have been processed from the Titan flybys spanning three years now since SOI (Flasar et al., 2005; Teanby et al., 2006, Vinatier et al., 2006; Nixon et al., 2006; Coustenis et al., 2007). The spectra characterize various regions on Titan from 85°S to 80°N with a variety of emission angles. We have studied the emission observed in the CIRS detector arrays (covering the 10-1500 cm-1 spectral range with apodized resolutions of 2.54 or 0.53 cm-1). We have used temperature profiles retrieved from the inversion of the emission observed in the methane band at 1304 cm-1 and a line-by-line radiative transfer code to infer the abundances of the trace constituents and some of their isotopes in Titan's stratosphere (Coustenis et al., 2007a). The composite spectra show several signatures of previously identified molecules: hydrocarbons, nitriles, H2O and CO2. Besides these well-known trace species, a firm detection of benzene (C6H6) is provided by CIRS at 674 cm-1 and allows for the study of its latitudinal variations. No longitudinal variations were found for any of the gases. Information is retrieved on the meridional variations of the trace constituents and tied to predictions by dynamical-photochemical models (Hourdin et al., 2004; Lavvas et al., 2007). Molecules showing a significant enhancement at northern latitudes are the nitriles (HC3N, HCN) and the complex hydrocarbons (C4H2, C3H4). The D/H ratio on Titan was

  10. Calibration of the Voyager Ultraviolet Spectrometers and the Composition of the Heliosphere Neutrals: Reassessment

    NASA Astrophysics Data System (ADS)

    Ben-Jaffel, Lotfi; Holberg, J. B.

    2016-06-01

    The data harvest from the Voyagers’ (V 1 and V 2) Ultraviolet Spectrometers (UVS) covers encounters with the outer planets, measurements of the heliosphere sky-background, and stellar spectrophotometry. Because their period of operation overlaps with many ultraviolet missions, the calibration of V1 and V2 UVS with other spectrometers is invaluable. Here we revisit the UVS calibration to assess the intriguing sensitivity enhancements of 243% (V1) and 156% (V2) proposed recently. Using the Lyα airglow from Saturn, observed in situ by both Voyagers, and remotely by International Ultraviolet Explorer (IUE), we match the Voyager values to IUE, taking into account the shape of the Saturn Lyα line observed with the Goddard High Resolution Spectrograph on board the Hubble Space Telescope. For all known ranges of the interplanetary hydrogen density, we show that the V1 and V2 UVS sensitivities cannot be enhanced by the amounts thus far proposed. The same diagnostic holds for distinct channels covering the diffuse He i 58.4 nm emission. Our prescription is to keep the original calibration of the Voyager UVS with a maximum uncertainty of 30%, making both instruments some of the most stable EUV/FUV spectrographs in the history of space exploration. In that frame, we reassess the excess Lyα emission detected by Voyager UVS deep in the heliosphere, to show its consistency with a heliospheric but not galactic origin. Our finding confirms results obtained nearly two decades ago—namely, the UVS discovery of the distortion of the heliosphere and the corresponding obliquity of the local interstellar magnetic field (˜ 40^\\circ from upwind) in the solar system neighborhood—without requiring any revision of the Voyager UVS calibration.

  11. Transient Events in Galactic Cosmic Rays Observed by Voyager-1 beyond the Heliopause

    NASA Astrophysics Data System (ADS)

    Kota, J.; Jokipii, J. R.

    2015-12-01

    Following the passage of Voyager-1 through the Heliopause in August 2012, anomalous cosmic rays essentially disappeared while galactic cosmic rays (GCRs) leveled to a remarkably constant flux. There were two notable exceptions: in March 2013 and May 2014 Voyager-1 experienced small increases of GCRs in the few hundred MeV range. Both events lasted a couple of weeks and were followed by detection of plasma oscillation (Gurnett et al., 2013, 2015). We shall discuss the pitch-angle distribution of GCRs, seen by LECP, and the time profiles of these events. We interpreted the first event as the GCRs remotely sensing a disturbance passing through the magnetic field line of Voyager-1: particles gained energy as they were reflected on the approaching region of stronger magnetic field of the disturbance. Here, we show that energy gain is not restricted to reflected particles, and the effect should be present at all pitch angles in the hemisphere facing the disturbance. The maximum increase of GCR intesity is predicted to occur at the critical reflection angle. The time profile starts with a sharp increase if GCRs are reflected from a sharp shock. However, the disturbance need not be very sharp. For instance, Voyager-1 magnetometer (Burlaga et al., 2013) detected a gradual 5-day increase of the field strength, B, in November 2012. A disturbance with a similar gradual profile would produce a smoother time-profile in the GCR flux at Voyager-1. We shall present numerical simulations and discuss their implications. Burlaga, L.F., et al., Astrophys. J., 778, L3 (2013)Gurnett, D.A., et a;., Science, 341, 1489 (2013)Gurnett, D.A., et al., Astrophys. J., in press (2105)

  12. My school voyages with PERSEUS - PERSEUS@SCHOOL

    NASA Astrophysics Data System (ADS)

    Fermeli, Georgia; Papathanassiou, Evangelos; Papatheodorou, George; Streftaris, Nikos; Ioakeimidis, Christos

    2014-05-01

    PERSEUS@SCHOOL is an international environmental education thematic school network which is inspired and supported by the European research project PERSEUS (Policy Oriented Marine Environmental Research in Southern European Seas_http://www.perseus-net.eu) which is funded by EU FP7 Theme "Ocean of Tomorrow" and it is coordinating by the Hellenic Centre for Marine Research (HCMR). The overall scientific objectives of PERSEUS (FP7) research project are to identify the interacting patterns of natural and human-derived pressures on the Mediterranean and Black Seas, assess their impact on marine ecosystems and, using the objectives and principles of the Marine Strategy Framework Directive as a vehicle, to design an effective and innovative research governance framework based on solid scientific knowledge. This research governance framework will engage scientists, policy-makers and the public, thereby reaching a shared understanding and informed decision-making based on sound scientific knowledge. PERSEUS@SCHOOL network is coordinated by the Department of Environmental Education of the 1st Directorate of Secondary Education of Athens and aims to help and enhance environmental education, focusing on clean seas stewardship in schools. Educators along with marine scientists have a role in supporting and inspiring children to acquire the knowledge, skills and inspire their awareness to live and work as responsible and concerned citizens. For this purpose, the network has designed specific pedagogical activities for primary and secondary education - based on PERSEUS key thematic areas i.e. Marine biodiversity, Overfishing, Chemical Marine Pollution - Bioaccumulation - Health, Eutrophication in Marine Waters and Marine Litter. Complementary, two web-monitoring tools will be used by the network; the Jellyfish Spotting campaign and the Marine LitterWatch (MLW) app (Developed by EEA). A special emphasis is given to MLW app, as school students for first time will use it in order to

  13. NASA Now Minute: Space Science: Voyager’s Grand Tour of the Solar System

    NASA Video Gallery

    Planetary scientist Lou Mayo discusses what we’re learning from theVoyager missions, where the two spacecraft are currently located andsome of the incredible discoveries made on the long journe...

  14. Telecommunications and data acquisition systems support for Voyager missions to Jupiter and Saturn, 1972-1981, prelaunch through Saturn encounter

    NASA Technical Reports Server (NTRS)

    Traxler, M. R.; Beauchamp, D. F.

    1983-01-01

    The Deep Space Network has supported the Voyager Project for approximately nine years, during which time implementation, testing, and operational support was provided. Four years of this time involved testing prior to launch; the final five years included network operations support and additional network implementation. Intensive and critical support intervals included launch and four planetary encounters. The telecommunications and data acquisition support for the Voyager Missions to Jupiter and Saturn are summarized.

  15. WHY ARE THE MAGNETIC FIELD DIRECTIONS MEASURED BY VOYAGER 1 ON BOTH SIDES OF THE HELIOPAUSE SO SIMILAR?

    SciTech Connect

    Grygorczuk, J.; Czechowski, A.; Grzedzielski, S.

    2014-07-10

    The solar wind carves a cavity in the interstellar plasma bounded by a surface, called the heliopause (HP), that separates the plasma and magnetic field of solar origin from those of interstellar origin. It is now generally accepted that in 2012 August Voyager 1 (V1) crossed that boundary. Unexpectedly, the magnetic fields on both sides of the HP, although theoretically independent of each other, were found to be similar in direction. This delayed the identification of the boundary as the HP and led to many alternative explanations. Here, we show that the Voyager 1 observations can be readily explained and, after the Interstellar Boundary Explorer (IBEX) discovery of the ribbon, could even have been predicted. Our explanation relies on the fact that the Voyager 1 and undisturbed interstellar field directions (which we assume to be given by the IBEX ribbon center (RC)) share the same heliolatitude (∼34.°5) and are not far separated in longitude (difference ∼27°). Our result confirms that Voyager 1 has indeed crossed the HP and offers the first independent confirmation that the IBEX RC is in fact the direction of the undisturbed interstellar magnetic field. For Voyager 2, we predict that the difference between the inner and outer magnetic field directions at the HP will be significantly larger than that observed by Voyager 1 (∼30° instead of ∼20°), and that the outer field direction will be close to the RC.

  16. Voyager 2 observations of plasmas and flows out to 104 AU

    SciTech Connect

    Richardson, J. D.; Decker, R. B. E-mail: robert.decker@apljhu.edu

    2014-09-10

    Voyager 2 has crossed through 20 AU of the heliosheath; assuming the same heliosheath thickness as at Voyager 1, it is now two-thirds of the way to the heliopause. The plasma data are generally of good quality, although the increasing flow angle of the plasma makes analysis more difficult. The average plasma speed has remained constant but the flow angles have increased to almost 60° in the RT plane and to almost 30° in the RN plane. The average density and thermal speed have been constant since a density increase observed in 2011. Comparison of V2 plasma flows derived from plasma science experiment (PLS) data and Low Energy Charged Particle (LECP) proton anisotropies give good agreement except when heavy ion contributions or non-convective proton anisotropies are observed in the LECP data.

  17. Absolute far-ultraviolet spectrophotometry of hot subluminous stars from Voyager

    SciTech Connect

    Holberg, J.B.; Ali, B.; Carone, T.E.; Polidan, R.S. NASA, Goddard Space Flight Center, Greenbelt, MD )

    1991-07-01

    Observations, obtained with the Voyager ultraviolet spectrometers, are presented of absolute fluxes for two well-known hot subluminous stars: BD + 28 deg 4211, an sdO, and G191 - B2B, a hot DA white dwarf. Complete absolute energy distributions for these two stars, from the Lyman limit at 912 A to 1 micron, are given. For BD + 28 deg 4211, a single power law closely represents the entire observed energy distribution. For G191 - B2B, a pure hydrogen model atmosphere provides an excellent match to the entire absolute energy distribution. Voyager absolute fluxes are discussed in relation to those reported from various sounding rocket experiments, including a recent rocket observation of BD + 28 deg 4211. 43 refs.

  18. Voyager 1 explores the termination shock region and the heliosheath beyond.

    PubMed

    Stone, E C; Cummings, A C; McDonald, F B; Heikkila, B C; Lal, N; Webber, W R

    2005-09-23

    Voyager 1 crossed the termination shock of the supersonic flow of the solar wind on 16 December 2004 at a distance of 94.01 astronomical units from the Sun, becoming the first spacecraft to begin exploring the heliosheath, the outermost layer of the heliosphere. The shock is a steady source of low-energy protons with an energy spectrum approximately E(-1.41 +/- 0.15) from 0.5 to approximately 3.5 megaelectron volts, consistent with a weak termination shock having a solar wind velocity jump ratio r=2.6(-0.2)(+0.4). However, in contradiction to many predictions, the intensity of anomalous cosmic ray (ACR) helium did not peak at the shock, indicating that the ACR source is not in the shock region local to Voyager 1. The intensities of approximately 10-megaelectron volt electrons, ACRs, and galactic cosmic rays have steadily increased since late 2004 as the effects of solar modulation have decreased.

  19. Forward and reverse shocks in the outer heliosphere: Observations from Voyager 2

    NASA Technical Reports Server (NTRS)

    Lazarus, A. J.; Belcher, J. W.; Paularena, K. I.; Richardson, J. D.; Steinberg, J. T.; Pizzo, V. J.; Gosling, J. T.

    1995-01-01

    Observations from Voyager 2 as it moved from 10 to 14 deg S heliographic latitude in the period from 1992 through 1994 were used to gather statistics on the relative number of forward and reverse shocks. These results can be used to compare with observations from the Ulysses spacecraft which moved from 6 deg S to 70 deg S heliographic latitude during that time period. The Ulysses observations are in agreement with a 3-D, MHD model of the evolution of a steady tilted-dipole solar wind flow configuration prevalent in 1993. The model predicts and the Ulysses observations confirm a preponderance of reverse shocks at Ulysses latitudes poleward of streamer-belt latitudes. A preliminary scan of the Voyager data supports the complementary prediction of the model that forward fronts should dominate at large heliocentric distances near the heliographic equatorial plane during the same time period.

  20. Search for the exit: Voyager 1 at heliosphere's border with the galaxy.

    PubMed

    Krimigis, S M; Decker, R B; Roelof, E C; Hill, M E; Armstrong, T P; Gloeckler, G; Hamilton, D C; Lanzerotti, L J

    2013-07-12

    We report measurements of energetic (>40 kiloelectron volts) charged particles on Voyager 1 from the interface region between the heliosheath, dominated by heated solar plasma, and the local interstellar medium, which is expected to contain cold nonsolar plasma and the galactic magnetic field. Particles of solar origin at Voyager 1, located at 18.5 billion kilometers (123 astronomical units) from the Sun, decreased by a factor of >10(3) on 25 August 2012, while those of galactic origin (cosmic rays) increased by 9.3% at the same time. Intensity changes appeared first for particles moving in the azimuthal direction and were followed by those moving in the radial and antiradial directions with respect to the solar radius vector. This unexpected heliospheric "depletion region" may form part of the interface between solar plasma and the galaxy.

  1. Performance of three-way data types during Voyager's encounter with Neptune

    NASA Technical Reports Server (NTRS)

    Roth, D. C.; Taylor, T. H.; Jacobson, R. A.; Lewis, G. D.

    1990-01-01

    Voyager's flyby of Neptune in August of 1989 was the most distant planetary encounter ever achieved. Round trip light travel time was more than eight hours, exceeding view periods at two of the three tracking station sites. Consequently, the majority of radiometric tracking was accomplished by transmitting the uplink from one station, and receiving the downlink at a different station. This procedure defines three-way data. Dependence on three-way data for orbit determination is one distinguishing element of Voyager's successful encounter with Neptune. This paper addresses the performance of three-way range and Doppler data supporting pre-encounter orbit determination and post-encounter orbit reconstruction. Also, calibrations which reduce systematic errors inherent to three-way data are described and analyzed.

  2. Voyager 1 observes low-energy galactic cosmic rays in a region depleted of heliospheric ions.

    PubMed

    Stone, E C; Cummings, A C; McDonald, F B; Heikkila, B C; Lal, N; Webber, W R

    2013-07-12

    On 25 August 2012, Voyager 1 was at 122 astronomical units when the steady intensity of low-energy ions it had observed for the previous 6 years suddenly dropped for a third time and soon completely disappeared as the ions streamed away into interstellar space. Although the magnetic field observations indicate that Voyager 1 remained inside the heliosphere, the intensity of cosmic ray nuclei from outside the heliosphere abruptly increased. We report the spectra of galactic cosmic rays down to ~3 × 10(6) electron volts per nucleon, revealing H and He energy spectra with broad peaks from 10 × 10(6) to 40 × 10(6) electron volts per nucleon and an increasing galactic cosmic-ray electron intensity down to ~10 × 10(6) electron volts.

  3. COMPARISON OF HELIOSPHERIC MODELS WITH OBSERVATIONS OF THE VOYAGER AND IBEX SPACECRAFT

    SciTech Connect

    Strumik, M.; Ratkiewicz, R.; Grygorczuk, J.; Ben-Jaffel, L.

    2011-11-01

    Results of modeling the heliosphere are compared with observations of the Voyager spacecraft and the IBEX mission simultaneously. The MHD solutions are tested against observational data for different strengths and orientations of the local interstellar magnetic field (LIMF) used in the simulations for asymmetric magnetized solar wind flow. We show that the model reproduces approximately the position of the IBEX ribbon and the termination shock crossing distance for Voyager 2, when the LIMF vector lies in the proximity of the hydrogen deflection plane with the inclination angle to the local interstellar flow equal to 39 deg. {+-} 9 deg. and its magnitude is 2.4 {+-} 0.3 {mu}G. In ecliptic coordinates this solution corresponds to the LIMF vector pointing from (longitude, latitude) = (227 deg. {+-} 7 deg., 35 deg. {+-} 7 deg.).

  4. The near real time image navigation of pictures returned by Voyager 2 at Neptune

    NASA Technical Reports Server (NTRS)

    Underwood, Ian M.; Bachman, Nathaniel J.; Taber, William L.; Wang, Tseng-Chan; Acton, Charles H.

    1990-01-01

    The development of a process for performing image navigation in near real time is described. The process was used to accurately determine the camera pointing for pictures returned by the Voyager 2 spacecraft at Neptune Encounter. Image navigation improves knowledge of the pointing of an imaging instrument at a particular epoch by correlating the spacecraft-relative locations of target bodies in inertial space with the locations of their images in a picture taken at that epoch. More than 8,500 pictures returned by Voyager 2 at Neptune were processed in near real time. The results were used in several applications, including improving pointing knowledge for nonimaging instruments ('C-smithing'), making 'Neptune, the Movie', and providing immediate access to geometrical quantities similar to those traditionally supplied in the Supplementary Experiment Data Record.

  5. Jupiter Data Analysis Program: Analysis of Voyager wideband plasma wave observations

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.

    1983-01-01

    Voyager plasma wave wideband frames from the Jovian encounters are analyzed. The 511 frames which were analyzed were chosen on the basis of low-rate spectrum analyzer data from the plasma wave receiver. These frames were obtained in regions and during times of various types of plasma or radio wave activity as determined by the low-rate, low-resolution data and were processed in order to provide high resolution measurements of the plasma wave spectrum for use in the study of a number of outstanding problems. Chorus emissions at Jupiter were analyzed. The detailed temporal and spectral form of the very complex chorus emissions near L = 8 on the Voyager 1 inbound passage was compared to both terrestrial chorus emissions as well as to the theory which was developed to explain the terrestrial waves.

  6. A new spectrum of Triton near the time of the Voyager encounter

    NASA Technical Reports Server (NTRS)

    Grundy, William M.; Fink, Uwe

    1991-01-01

    A 5200-10,000 A spectrum of Triton that was telescopically obtained during the summer of 1989, just before the Voyager II encounter with the Neptune system, exhibits a measurable 8900 A CH4 ice absorption band. A combination of these data with those of Voyager indicates that the absorption is caused solely by Triton surface CH4 ice. A Hapke-type model for the Triton spectrum (1) sets a 20-micron lower limit on the CH4 ice's mean grain size (although it is suspected that actual grain size is closer to 100 microns), and (2) indicates that CH4 ice is widely distributed on the southern-hemisphere surface of Triton.

  7. Geology and Topography of Ra Patera, Io, in the Voyager era: Prelude to Eruption

    NASA Technical Reports Server (NTRS)

    Schenk, Paul M.; McEwen, Alfred; Davies, A. G.; Davenport, Trevor; Jones, Kevin; Fessler, Brian

    1997-01-01

    Voyager era stereo images are used to map the geology and topography of Ra Patera (a major active volcanic center and possible site of sulfur eruptions on Io). The summit of Ra Patera reaches only approx.1 km above the surrounding plains. Pre-Voyager-era lava flows occur on slopes of 0.1-0.3 deg, comparable to the lunar mare. These flows were emplaced at either low viscosities, high eruption rates, or both. A 600- km-long ridged mountain unit (rising to approx. 8 km near Carancho Patera) forms a 60 by 90 km wide plateau approx. 0.5 km high 50 km east of Ra Patera. The new lava flows observed by Galileo flowed around the southern edge of this plateau.

  8. Absolute far-ultraviolet spectrophotometry of hot subluminous stars from Voyager

    NASA Technical Reports Server (NTRS)

    Holberg, J. B.; Ali, B.; Carone, T. E.; Polidan, R. S.

    1991-01-01

    Observations, obtained with the Voyager ultraviolet spectrometers, are presented of absolute fluxes for two well-known hot subluminous stars: BD + 28 deg 4211, an sdO, and G191 - B2B, a hot DA white dwarf. Complete absolute energy distributions for these two stars, from the Lyman limit at 912 A to 1 micron, are given. For BD + 28 deg 4211, a single power law closely represents the entire observed energy distribution. For G191 - B2B, a pure hydrogen model atmosphere provides an excellent match to the entire absolute energy distribution. Voyager absolute fluxes are discussed in relation to those reported from various sounding rocket experiments, including a recent rocket observation of BD + 28 deg 4211.

  9. A Study of Saturn's E-Ring Particles Using the Voyager 1 Plasma Wave Instrument

    NASA Technical Reports Server (NTRS)

    Tsintikidis, D.; Kurth, W. S.; Gurnett, D. A.; Barbosa, D. D.

    1993-01-01

    The flyby of Voyager 1 at Saturn resulted in the detection of a large variety of plasma waves, e.g., chorus, hiss, and electron cyclotron harmonics. Just before the outbound equator crossing, at about 6.1 R(sub s), the Voyager 1 plasma wave instrument detected a strong, well-defined low-frequency enhancement. Initially it was suggested that plasma waves might be responsible for the spectral feature but more recently dust was suggested as at least a partial contributor to the enhancement. In this report we present evidence which supports the conclusion that dust contributes to the low-frequency enhancement. A new method has been used to derive the dust impact rate. The method relies mainly on the 16-channel spectrum analyzer data. The few wide band waveform observations available (which have been used to study dust impacts during the Voyager 2 ring plane crossing) were useful for calibrating the impact rate from the spectrum analyzer data. The mass and, hence, the size of the dust particles were also obtained by analyzing the response of the plasma wave spectrum analyzer. The results show that the region sampled by Voyager 1 is populated by dust particles that have rms masses of up to few times 10(exp -11) g and sizes of up to a few microns. The dust particle number density is on the order of 10(exp -3) m(exp 3). The optical depth of the region sampled by the spacecraft is 1.04 x 10(exp -6). The particle population is centered about 2500 km south of the equatorial plane and has a north-south thickness of about 4000 km. Possible sources of these particles are the moons Enceladus and Tethys whose orbits lie within the E-ring radial extent. These results are in reasonable agreement with photometric studies and numerical simulations.

  10. A Voyage to Vardoe. A Scientific Account of an Unscientific Expedition

    NASA Astrophysics Data System (ADS)

    Sterken, Christiaan; Aspaas, Per Pippin; Duner, David; Kontler, Laszlo; Neul, Reinhard; Pekonen, Osmo; Posch, Thomas

    2013-05-01

    After the "Venus Transit Conference" that took place at the University of Tromsoe from June 2 to June 3, 2012, participants were given the opportunity to either stay in Tromsoe until the night of June 5-6, or to participate in a voyage to Finnmark, where the historical sites Vardoe, Hammerfest, and the North Cape were to be visited. This voyage culminated in the observation of the 2012 transit of Venus at Vardoe. This paper gives a detailed account of this voyage that lasted from June 3 to June 6, and emphasizes the historical, scientific, philosophical, educational and cultural involvement of the participants of the voyage and of the local population. The paper concludes with reflections on the prime condition for success of any of the Venus transit expeditions of the past: the weather must cooperate in the first place - not only during the quarter of a day of the transit, but also during the preceding weeks and months in order to allow the explorers to rightly determine their geographic positions and correctly set their clocks. The latter factor is no longer an issue nowadays, but the weather aspect remains today a limiting factor as much as it was 250 years ago. Despite the variable and partly clouded weather at Vardoe during the time of the transit, the participants of this expedition were able to observe Venus in front of the Sun - with interruptions due to quickly moving clouds - between 4.30 a.m. and the fourth contact at 06:53:20 a.m. A large number of impressive, partly `dramatic' photographs have been taken especially in this time interval.

  11. Electron density of local interstellar medium, based on the Voyager heliospheric-shock observations

    SciTech Connect

    Baranov, V.B.

    1986-10-01

    Some implications of a model for the solar wind-local-interstellar-medium (LISM) interaction, comprising a bow shock and a heliospheric shock with a contact interface in between, are compared against the Voyager probe data. A fit can be achieved if the LISM electron density is somewhat higher than indicated by pulsar dispersion measurements. The theory is compatible with the hydrogen densities inferred from Copernicus and from the scattering solar L-alpha radiation. 14 references.

  12. A 'private adventure'? John Herschel's Cape voyage and the production of the 'Cape Results'

    NASA Astrophysics Data System (ADS)

    Ruskin, Steven William

    2002-07-01

    This dissertation considers the life of John Herschel (1792 1871) from the years 1833 to 1847. In 1833 Herschel sailed from London to Cape Town, southern Africa, to undertake (at his own expense) an astronomical exploration of the southern heavens, as well as a terrestrial exploration of the area around Cape Town. After his return to England in 1838, he was highly esteemed and became Britain's most recognized scientist. In 1847 his southern hemisphere astronomical observations were published as the Cape Results. The main argument of this dissertation is that Herschel's voyage, and the publication of the Cape Results, in addition to their contemporary scientific importance, were also significant for nineteenth-century politics and culture. This dissertation is a two-part dissertation. The first part is entitled “John Herschel's Cape Voyage: Private Science, Public Imagination, and the Ambitions of Empire”; and the second part, “The Production of the Cape Results.” In the first part it is demonstrated that the reason for Herschel's cultural renown was the popular notion that his voyage to the Cape was a project aligned with the imperial ambitions of the British government. By leaving England for one of its colonies, and pursuing there a significant scientific project, Herschel was seen in the same light as other British men of science who had also undertaken voyages of exploration and discovery. It is then demonstrated, in the second part of this work, that the production of the Cape Results, in part because of Herschel's status as Britain's scientific figurehead, was a significant political and cultural event. In addition to the narrow area of Herschel scholarship, this dissertation touches on other areas of research in the history of science as well: science and culture, science and empire, science and politics, and what has been called the “new” history of scientific books.

  13. Carbon-14 dating of an iron bloom associated with the voyages of Sir Martin Frobisher

    SciTech Connect

    Sayre, E.V.; Harbottle, G.; Stoenner, R.W. Washburn, W.; Olin, J.S.; Fitzhugh, W.

    1982-01-01

    This paper recounts the history of the iron bloom associated with the English Elizabethan explorer Sir Martin Frobisher who made 3 voyages to the North American mainland in the 1570's. Specifically the paper deals with the use of proportional counters in carbon-14 dating of the Frobisher iron bloom which is located at the Smithsonian Institution. The procedures for preparing the samples for counting are described. (KRM)

  14. Selecting and implementing scientific objectives. [for Voyager 1 and 2 planetary encounters

    NASA Technical Reports Server (NTRS)

    Miner, E. D.; Stembridge, C. H.; Doms, P. E.

    1985-01-01

    The procedures used to select and implement scientific objectives for the Voyager 1 and 2 planetary encounters are described. Attention is given to the scientific tradeoffs and engineering considerations must be addressed at various stages in the mission planning process, including: the limitations of ground and spacecraft communications systems, ageing of instruments in flight, and instrument calibration over long distances. The contribution of planetary science workshops to the definition of scientific objectives for deep space missions is emphasized.

  15. Pointing calibration of the MKIVA DSN antennas Voyager 2 Uranus encounter operations support

    NASA Technical Reports Server (NTRS)

    Stevens, R.; Riggs, R. L.; Wood, B.

    1986-01-01

    The MKIVA DSN introduced significant changes to the pointing systems of the 34-meter and 64-meter diameter antennas. To support the Voyager 2 Uranus Encounter, the systems had to be accurately calibrated. Reliable techniques for use of the calibrations during intense mission support activity had to be provided. This article describes the techniques used to make the antenna pointing calibrations and to demonstrate their operational use. The results of the calibrations are summarized.

  16. Quantitative measurements of Jupiter, Saturn, their rings and satellites made from Voyager imaging data

    NASA Technical Reports Server (NTRS)

    Collins, S. A.; Bunker, A. S.

    1983-01-01

    The Voyager spacecraft cameras use selenium-sulfur slow scan vidicons to convert focused optical images into sensible electrical signals. The vidicon-generated data thus obtained are the basis of measurements of much greater precision than was previously possible, in virtue of their superior linearity, geometric fidelity, and the use of in-flight calibration. Attention is given to positional, radiometric, and dynamical measurements conducted on the basis of vidicon data for the Saturn rings, the Saturn satellites, and the Jupiter atmosphere.

  17. On the inclusion of the hydrogen dimer in the analysis of Voyager IRIS spectra

    NASA Technical Reports Server (NTRS)

    Carlson, Barbara E.; Ma, Qiancheng; Lacis, Andrew

    1992-01-01

    Empirical formulas are fitted to existing theoretical absorption spectra of H2-H2 pairs in the far-infrared allowing the inclusion of dimer absorption, parameterized with the height dependence of the para-hydrogen profile, in the calculations. Comparison between synthetic and Voyager IRIS spectra shows that once the dimer absorption is included it is now possible to reproduce the hydrogen portion of the IRIS spectrum to within the precision of the measurements.

  18. Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle.

    PubMed

    Petren, Kenneth; Grant, Peter R; Grant, B Rosemary; Clack, Andrew A; Lescano, Ninnia V

    2010-04-12

    Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded. Using 'ancient' DNA techniques, we quantified variation at 14 autosomal microsatellite loci. Assignment tests showed several museum specimens genetically matched recently field-sampled birds from their island of origin. Some were misclassified or were difficult to classify. Darwin's exceptionally large ground finches (Geospiza magnirostris) from Floreana and San Cristóbal were genetically distinct from several other currently existing populations. Sharp-beaked ground finches (Geospiza difficilis) from Floreana and Isabela were also genetically distinct. These four populations are currently extinct, yet they were more genetically distinct from congeners than many other species of Darwin's finches are from each other. We conclude that a significant amount of the finch biodiversity observed and collected by Darwin has been lost since the voyage of the Beagle. PMID:20194164

  19. Voyager observations of O(+6) and other minor ions in the solar wind

    NASA Technical Reports Server (NTRS)

    Villanueva, Louis; Mcnutt, Ralph L., Jr.; Lazarus, Alan J.; Steinberg, John T.

    1994-01-01

    The plasma science (PLS) experiments on the Voyager 1 and 2 spacecraft began making measurements of the solar wind shortly after the two launches in the fall of 1977. In reviewing the data obtained prior to the Jupiter encounters in 1979, we have found that the large dynamic range of the PLS instrument generally allows a clean separation of signatures of minor ions (about 2.5% of the time) during a single instrument scan in energy per charge. The minor ions, most notably O(+6), are well separated from the protons and alpha particles during times when the solar wind Mach number (ratio of streaming speed to thermal speed) is greater than approximately 15. During the Earth to Jupiter cruise we find that the average ratio of alpha particle number density to that of oxygen is 66 +/- 7 (Voyager 1) and 71 +/- 17 (Voyager 2). These values are consistent with the value 75 +/- 20 inferred from the Ion Composition Instrument on ISEE 3 during the period spanning 1978 and 1982. We have inferred an average coronal temperature of (1.7 +/- 0.1) x 10(exp 6) K based on the ratio of O(+7) to O(+6) number densities. Our observations cover a period of increasing solar activity. During this time we have found that the alpha particle to proton number density ratio is increasing with the solar cycle, the oxygen to proton ratio increases, and the alpha particle to oxygen ratio remains relatively constant in time.

  20. Re-acceleration of galactic electrons at the termination shock and its role in Voyager observations

    NASA Astrophysics Data System (ADS)

    Prinsloo, Phillip; Toit Strauss, Du; Potgieter, Marius

    2016-07-01

    The Voyager spacecraft have had a number of notable achievements, with the crossing of the TS certainly being among them. Observations of 0.35 to 14 MeV electron intensities in the proximity of the termination shock show narrow peak-like increases, which are thought to result, at least in part, due to diffusive shock acceleration. Using a numerical cosmic-ray modulation model, it is shown that this acceleration mechanism can indeed account for the magnitude of the peaks observed by Voyager 1 and 2. Additionally, the contribution of re-accelerated electrons to overall intensities in the heliosheath is revealed to be significant despite the low-diffusion conditions reigning in this region. With the appropriate specification of the rigidity dependence of diffusion coefficients in the transport equation, and including therein the dissipation-range contribution of magnetic turbulence, the form of the energy distribution observed by Voyager 1 at the termination shock is also reproduced with the inclusion of diffusive shock acceleration.

  1. The solar wind density spectrum near the Sun: Results from Voyager radio measurements

    SciTech Connect

    Coles, W.A.; Liu, W. ); Harmon, J.K.; Martin, C.L. )

    1991-02-01

    Spacecraft radio propagation data are analyzed to estimate the solar wind density fluctuation power spectrum across five decades of spatial wave number. The data were from radio science observations made during superior conjunctions of the Voyager 1 and Voyager 2 spacecrafts in 1979 and 1980. These data were analyzed to yield the wave structure function, a statistic which is related to, but obtained more readily than, the spectrum itself. Structure functions were obtained from a total of 28 observations spanning the heliocentric distance range 7-22 R{sub S}. Each structure function was a composite of two shorter segments estimated, respectively, from phase scintillation and spectral broadening analyses. The composite structure functions tend to be steep (approximately Kolmogorov) at large scales (10{sup 3}-10{sup 6} km) and nearly always show some flattening at smaller scales (10-100 km). The inflection between the steep and flatter regions is abrupt and occurs at scales of 100-300 km. Most of the structure functions also show some turnover at the very smallest scales. These results are in excellent agreement with the spectral shape model proposed by Coles and Harmon (1989). A few transients were seen in the Voyager data which were characterized by an overall increase in power at large scales and a steeping of the structure function at small scales. These transients were similar in appearance to transients reported earlier from Arecibo spectral broadening observations.

  2. New analysis of the Voyager UVS H Lyman-alpha emission of Saturn

    NASA Technical Reports Server (NTRS)

    Jaffel, L. Ben; Prange, R.; Sandel, B. R.; Yelle, R. V.; Emerich, C.; Feng, D.; Hall, D. T.

    1995-01-01

    The limb to limb Lyman-alpha reflectivities observed with the Voyager ultraviolet spectrometer (UVS) instruments during the fly-by of Saturn are reanalyzed using a revised H Lyman-alpha sensitivity for the Voyager 1 instrument. The new sensitivity reconciles the measured intensities to those of Voyager 2 and gives a coherent set of data. To fit the UV airglow observations, four sources are considered: (1) H resonance and H2 Rayleigh scattering of solar Lyman-alpha radiation, (2) the interplanetary Lyman-alpha radiation, (3) a possible internal source of unknown origin, (4) the possibility of atmospheric turbulence recently proposed to explain the Lyman-alpha bulge of Jupiter. The analysis supports neither a dominant collisional excitation source for the UV emissions nor the presence of strong atmospheric turbulence. The best fit, in terms of brightness but also in terms of shape of the limb to limb profile (that is to say independent on the absolute calibrations), is obtained for pure resonance and Rayleigh scattering of solar and interstellar wind line in an atmosphere enriched in atomic hydrogen up to three times the standard model. Influx of water from the rings of Saturn may provide a means for producing such enhanced H densities in the upper atmosphere.

  3. Distribution of Heavy Ions in the Jovian Magnetosphere from Re-Analysis of Voyager PLS Data

    NASA Astrophysics Data System (ADS)

    Dougherty, L.; Bagenal, F.; Wilson, R. J.; Bodisch, K. M.

    2015-12-01

    Jupiter's magnetosphere is populated with heavy ions produced by ionization of volcanic gases from Io. The 1979 flybys of the Voyager 1 and 2 spacecraft through the Jovian system provided in situ measurements of plasma properties by the Plasma Science (PLS) instruments. Re-analysis of the Voyager 1 and 2 PLS data, combined with constraints from EUV emissions, allow a more detailed description of the distribution of heavier ions throughout the entire Jovian magnetosphere. The PLS instrument on the Voyager spacecraft had a large angle of view, with 4 Faraday cups covering different portions of the sky. This allows for an accurate determination of the properties of the plasma, including density, temperature, and flow speed, assuming a convected Maxwellian distribution. We determine densities of S+, S++, S+++, O+, and O++ ions mapped out to 30 RJ. Because the instrument measures a current as a function of energy/charge, there is an ambiguity in the measurement of the density of the dominant species O+ and S++. To resolve this issue we use a chemistry model to constrain the relative amounts of these two species throughout the magnetosphere.

  4. On the latitudinal distribution of Titan's haze at the Voyager epoch

    NASA Astrophysics Data System (ADS)

    Negrao, A.; Roos-Serote, M.; Rannou, P.; Rages, K.; McKay, C.

    2002-09-01

    In this work, we re-analyse a total of 10 high phase angle images of Titan (2 from Voyager 1 and 8 from Voyager 2). The images were acquired in different filters of the Voyager Imaging Sub System in 1980 - 1981. We apply a model, developed and used by Rannou etal. (1997) and Cabane etal. (1992), that calculates the vertical (1-D) distribution of haze particles and the I/F radial profiles as a function of a series of parameters. Two of these parameters, the haze particle production rate (P) and imaginary refractive index (xk), are used to obtain fits to the observed I/F profiles at different latitudes. Differerent from previous studies is that we consider all filters simultaneously, in an attempt to better fix the parameter values. We also include the filter response functions, not considered previously. The results show that P does not change significantly as a function of latitude, eventhough somewhat lower values are found at high northern latitudes. xk seems to increase towards southern latitudes. We will compare our results with GCM runs, that can give the haze distribution at the epoch of the observations. Work financed by portuguese Foundation for Science and Tecnology (FCT), contract ESO/PRO/40157/2000

  5. New local interstellar spectra for protons, Helium and Carbon computed from Voyager 1 and PAMELA observations

    NASA Astrophysics Data System (ADS)

    Bisschoff, Driaan; Potgieter, Marius

    2016-07-01

    The comparison of computed galactic spectra with experimental, in situ data at lower energies is finally possible with the cosmic ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere. Galactic spectra computed by galactic propagation models and considered to be local interstellar spectra (LIS), for specifically protons, Helium and Carbon nuclei, can now be compared with observations at low energies (less than 100 MeV/nuc) from Voyager 1 and at high energies (above 30 GeV/nuc) from the PAMELA space detector at the Earth. We set out to reproduce the Voyager 1 observations beyond the heliopause using the GALPROP code and the PAMELA spectra at the Earth via a comprehensive solar modulation model. By varying the galactic diffusion parameters in the GALPROP plain diffusion model, specifically the rigidity dependence of spatial diffusion, and then including reacceleration in Galactic space, we compute spectra simultaneously for galactic protons, Helium and Carbon. These LIS are then used as input to a full 3D solar modulation model to test the spectra against the PAMELA measurements. We present new LIS, with expressions for the energy range of 3 MeV/nuc to 100 GeV/nuc, which should be most valuable for further solar modulation modelling.

  6. Investigating the Spectral Evolution of Anomalous Cosmic Rays at Voyager 1

    NASA Astrophysics Data System (ADS)

    Senanayake, Udara; Cummings, A. C.; Stone, E. C.; Florinski, Vladimir

    Anomalous cosmic rays (ACRs) were thought to be accelerated at the solar wind termination shock by the diffusive shock acceleration process. When Voyager 1 crossed the termination shock in 2004, the measured ACR spectra did not match the theoretical prediction of a continuous power law, and the source of the high-energy ACRs was not observed. Then, ACR spectra started to unfold in the heliosheath during the declining phase of the solar cycle 23. In this work, a three-dimensional magnetohydrodynamic background model with constant solar wind boundary conditions is applied to Helium and Oxygen ACRs. Further, we use a backward-in-time stochastic integration technique where phase-space trajectories are integrated until 0.5 MeV/n is reached. Solar activity effects can be simulated using changes in drifts and diffusion. We will use changes in heliospheric current sheet tilt angle and diffusion coefficient to investigate the spectral evolution of ACRs at Voyager 1. Our results will be compared with the Voyager 1 observations.

  7. Spectral Evolution of Anomalous Cosmic Rays at Voyager 1 Beyond the Termination Shock

    NASA Astrophysics Data System (ADS)

    Senanayake, U. K.; Florinski, V. A.; Cummings, A. C.; Stone, E. C.

    2014-12-01

    When Voyager 1 spacecraft crossed the termination shock on 16th December 2004, the energy spectra of anomalous cosmic rays (ACRs) could not have been produced by steady state diffusive shock acceleration. However, over the next few years, in the declining phase of the solar cycle, the spectra began to evolve into the expected power-law profile. Energetic particle transport coefficients, such as diffusion and drift, and also ACR source strength tend to increase with declining levels of solar activity. In this work, we propose that the solar cycle had an important effect on the "unrolling" spectra in the heliosheath at Voyager 1. To investigate the spectral evolution of ACRs, a magentohydrodynamic background model with stationary solar-wind inner boundary conditions will be used to model the transport of helium and oxygen ions. We use a backward-in- time stochastic integration technique where phase-space trajectories are integrated until the so called "injection energy" is reached. Our simulation results will be compared with Voyager 1 observations from 2005 to 2012.

  8. Thermal imaging of Uranus: Upper-tropospheric temperatures one season after Voyager

    NASA Astrophysics Data System (ADS)

    Orton, Glenn S.; Fletcher, Leigh N.; Encrenaz, Therese; Leyrat, Cedric; Roe, Henry G.; Fujiyoshi, Takuya; Pantin, Eric

    2015-11-01

    We report on 18-25 μm thermal imaging of Uranus that took place between 2003 and 2011, a time span roughly one season after the thermal maps made by the Voyager-2 IRIS experiment in 1986. We re-derived meridional variations of temperature and para-H2 fraction from the Voyager experiment and compared these with the thermal images, which are sensitive to temperatures in the upper troposphere of Uranus around the 70-400 mbar atmospheric pressure range. The thermal images display a maximum of 3 K of equivalent temperature changes across the disk, and they are consistent with the temperature distribution measured by the Voyager IRIS experiment. This implies that there has been no detectable change of the meridional distribution of upper-tropospheric/lower-stratospheric temperatures over a season. This is inconsistent with seasonally dependent radiative-convective-dynamical models and full global climate models that predict some variability with season if the effective temperature is meridionally constant. We posit that the effective temperature of Uranus could be meridionally variable, with the additional possibility that even the small temperature variations predicted by the GCMs are overestimated.

  9. Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle.

    PubMed

    Petren, Kenneth; Grant, Peter R; Grant, B Rosemary; Clack, Andrew A; Lescano, Ninnia V

    2010-04-12

    Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded. Using 'ancient' DNA techniques, we quantified variation at 14 autosomal microsatellite loci. Assignment tests showed several museum specimens genetically matched recently field-sampled birds from their island of origin. Some were misclassified or were difficult to classify. Darwin's exceptionally large ground finches (Geospiza magnirostris) from Floreana and San Cristóbal were genetically distinct from several other currently existing populations. Sharp-beaked ground finches (Geospiza difficilis) from Floreana and Isabela were also genetically distinct. These four populations are currently extinct, yet they were more genetically distinct from congeners than many other species of Darwin's finches are from each other. We conclude that a significant amount of the finch biodiversity observed and collected by Darwin has been lost since the voyage of the Beagle.

  10. Analysis of Clumps in Saturn’s F Ring from Voyager and Cassini Observations

    NASA Astrophysics Data System (ADS)

    French, Robert S.; Hicks, S. K.; Showalter, M. R.; Antonsen, A. K.; Packard, D. R.

    2013-10-01

    Saturn's F ring is well known for its unique and dynamic features that change on timescales from hours to months. Among these features are clumps, localized bright areas spanning ~3-30 degrees in longitude. 34 clumps tracked in Voyager images (Showalter 2004, Icarus, 171, 356-371) were found to live for several months and have a ~100 km spread in semi-major axis around the F ring core. Several clumps appeared to "split" during their lifetimes. Unfortunately, the poor resolution of the Voyager images and limited temporal and longitudinal coverage prevented a more detailed analysis. In this study, we performed a similar analysis using six years' worth of images from the Cassini Orbiter. We tracked 96 clumps and found similar angular widths, lifetimes, and semi-major axes to those observed by Voyager. However, the number of clumps present at one time appears to have decreased and the clumps are generally less bright; there are also many fewer extremely bright clumps. The better quality images allowed us to investigate five "splitting" clumps and we found that the apparent splits were often caused by the passage of the inner shepherd moon Prometheus. We further found that the birth and death of clumps appears uncorrelated with the position of Prometheus or with other features such as "mini-jets" or "jets" often found in the ring. We speculate on the changes in the population of embedded moonlets that may have resulted in these changes.

  11. A report on SHARP (Spacecraft Health Automated Reasoning Prototype) and the Voyager Neptune encounter

    NASA Technical Reports Server (NTRS)

    Martin, R. G. (Editor); Atkinson, D. J.; James, M. L.; Lawson, D. L.; Porta, H. J.

    1990-01-01

    The development and application of the Spacecraft Health Automated Reasoning Prototype (SHARP) for the operations of the telecommunications systems and link analysis functions in Voyager mission operations are presented. An overview is provided of the design and functional description of the SHARP system as it was applied to Voyager. Some of the current problems and motivations for automation in real-time mission operations are discussed, as are the specific solutions that SHARP provides. The application of SHARP to Voyager telecommunications had the goal of being a proof-of-capability demonstration of artificial intelligence as applied to the problem of real-time monitoring functions in planetary mission operations. AS part of achieving this central goal, the SHARP application effort was also required to address the issue of the design of an appropriate software system architecture for a ground-based, highly automated spacecraft monitoring system for mission operations, including methods for: (1) embedding a knowledge-based expert system for fault detection, isolation, and recovery within this architecture; (2) acquiring, managing, and fusing the multiple sources of information used by operations personnel; and (3) providing information-rich displays to human operators who need to exercise the capabilities of the automated system. In this regard, SHARP has provided an excellent example of how advanced artificial intelligence techniques can be smoothly integrated with a variety of conventionally programmed software modules, as well as guidance and solutions for many questions about automation in mission operations.

  12. Red Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  The Red Sea     View Larger Image ... Imaging SpectroRadiometer (MISR) image of the Red Sea was acquired on August 13, 2000. Located between the East African coast and the Saudi Arabian peninsula, the Red Sea got its name because the blooms of a type of algae,  Trichodesmium ...

  13. Introduction: SIPEX-2: A study of sea-ice physical, biogeochemical and ecosystem processes off East Antarctica during spring 2012

    NASA Astrophysics Data System (ADS)

    Meiners, Klaus M.; Golden, Ken M.; Heil, Petra; Lieser, Jan L.; Massom, Rob; Meyer, Bettina; Williams, Guy D.

    2016-09-01

    This editorial introduces a suite of articles resulting from the second Sea Ice Physics and Ecosystems eXperiment (SIPEX-2) voyage by presenting some background information on the study area and Antarctic sea-ice conditions, and summarising the key findings from the project. Using the Australian icebreaker RV Aurora Australis, SIPEX-2 was conducted in the area between 115-125°E and 62-66°S off East Antarctica during September to November 2012. This region had been sampled during two previous experiments, i.e. ARISE in 2003 (Massom et al., 2006a) and SIPEX in 2007 (Worby et al., 2011a). The 2012 voyage combined traditional and newly developed sampling methods with satellite and other data to measure sea-ice physical properties and processes on large scales, which provided context for biogeochemical and ecological case studies. The specific goals of the SIPEX-2 project were to: (i) measure the spatial variability in sea-ice and snow-cover properties over small- to regional-length scales; (ii) improve understanding of sea-ice kinematic processes; and (iii) advance knowledge of the links between sea-ice physical characteristics, sea-ice biogeochemical cycling and ice-associated food-web dynamics. Our field-based activities were designed to inform modelling approaches and to improve our capability to assess impacts of predicted changes in Antarctic sea ice on Southern Ocean biogeochemical cycles and ecosystem function.

  14. Grant Proposal for the Continuation of the Voyager Interstellar Mission: LECP Investigation

    NASA Technical Reports Server (NTRS)

    Krimigis, Stamatios M.; Armstrong, Thomas P.; Lanzerotti, Louis J.; Ip, Wing-H.; Decker, Robert B.; Keath, Edwin P.; Mauk, Barry H.; McNutt, Ralph L., Jr.; Gloeckler, George; Hamilton, Douglas C.

    1996-01-01

    This proposal documents the plans of the Low Energy Charged Particle (LECP) investigation team for participation in NASA's Voyager Interstellar Mission (VIM) as the Voyager 1 and 2 spacecraft explore the outer reaches of the heliosphere and search for the termination shock and the heliopause. The proposal covers the four year period from 1 January 1997 to 31 December 2000. The LECP instruments on Voyager 1 and 2 measure in situ intensities of charged particles with energies from about 30 keV to 100 MeV for ions, and about 20 keV to greater than 10 MeV for electrons. The instruments provide detailed spectral, angular, and compositional information about the particles. Composition is available for greater than 200 keV/nuc using multi-parameter measurements. Angular information is obtained by a mechanically scanned platform that rotates at various commanded rates. Measurements of low energy ion and electron intensities versus time and spatial location within the heliosphere contain an abundance of information regarding various transport and acceleration processes on both local (approx. 1 hr, approx. 0.01 AU) and global (approx. 11 yrs, approx. 100 AU) scales. The LECP instruments provide unique observations of such dynamical processes, and we anticipate that it will return critical information regarding the boundaries of the heliosphere. Several recent and exciting discoveries based on LECP measurements emphasize the important role that low energy charged particle distributions play in physical processes in the interplanetary medium. Yet, at the same time, these discoveries also underscore the fact that our understanding of processes in the outer heliosphere is, in most cases, incomplete, and in others, only rudimentary at best. Among the discoveries referred to above are the following: (1) Shocks: Examination of greater than 30 keV ion intensities have revealed: (a) a total absence of acceleration beyond only -100-200 keV at a strong transient shock in May 1991 at 35

  15. Factors influencing the en route survivorship and post-voyage growth of a common ship biofouling organism, Bugula neritina.

    PubMed

    Schimanski, Kate B; Piola, Richard F; Goldstien, Sharyn J; Floerl, Oliver; Grandison, Clare; Atalah, Javier; Hopkins, Grant A

    2016-09-01

    The likelihood that viable non-indigenous biofouling species will survive a voyage on a vessel is influenced by a range of factors, including the speed, duration, and route of the voyage and the amount of time the vessel spends in port. In this study, a land-based dynamic flow device was used to test the effect of recruit age, vessel speed and voyage duration on the survivorship and growth of the bryozoan Bugula neritina. In the experiment, one-week-old recruits had a higher likelihood (100%) of surviving voyages than older (one-month-old, 90%) or younger (one-day-old, 79%) recruits, but survival was not influenced by vessel speed (6 and 18 knots) or voyage duration (two and eight days). The results suggest that the non-indigenous species B. neritina can be effectively transferred at a range of ages but one-week-old recruits are more likely to survive the translocation process and survive in the recipient environment. PMID:27539565

  16. John Lawson's "A New Voyage to Carolina": notes on the publication history of the London (1709) edition.

    PubMed

    Simpson, Marcus B; Simpson, Sallie W

    2008-01-01

    John Lawson's "A New Voyage to Carolina," an important source document for American colonial natural history, was first printed in 1709 in "A New Collection of Voyages and Travels," a two-volume set that also contained travel books translated by John Stevens. Lawson's publishers were leaders in the book trade of early eighteenth century London, and the "New Voyage" is typical of the resurgent popular interest in foreign travel narratives and exotic flora and fauna that began in the late 1600s. The "New Collection" was among the earliest examples of books published in serial instalments or fascicles, a marketing strategy adopted by London booksellers to broaden the audience and increase sales. Analysis of London issues of the "New Voyage" indicates that the 1709, 1711, 1714, and 1718 versions are simply bindings of the original, unsold sheets from the 1709 "New Collection" edition, differing only by new title-pages, front matter, and random stop-press corrections of type-set errors. Lawson's "New Voyage" illustrates important aspects of the British book trade during the hand press period of the early eighteenth century. PMID:19271343

  17. Factors influencing the en route survivorship and post-voyage growth of a common ship biofouling organism, Bugula neritina.

    PubMed

    Schimanski, Kate B; Piola, Richard F; Goldstien, Sharyn J; Floerl, Oliver; Grandison, Clare; Atalah, Javier; Hopkins, Grant A

    2016-09-01

    The likelihood that viable non-indigenous biofouling species will survive a voyage on a vessel is influenced by a range of factors, including the speed, duration, and route of the voyage and the amount of time the vessel spends in port. In this study, a land-based dynamic flow device was used to test the effect of recruit age, vessel speed and voyage duration on the survivorship and growth of the bryozoan Bugula neritina. In the experiment, one-week-old recruits had a higher likelihood (100%) of surviving voyages than older (one-month-old, 90%) or younger (one-day-old, 79%) recruits, but survival was not influenced by vessel speed (6 and 18 knots) or voyage duration (two and eight days). The results suggest that the non-indigenous species B. neritina can be effectively transferred at a range of ages but one-week-old recruits are more likely to survive the translocation process and survive in the recipient environment.

  18. SEAC 2011 Stars and Stones: Voyages in Archaeoastronomy and Cultural Astronomy

    NASA Astrophysics Data System (ADS)

    Pimenta, F.; Ribeiro, N.; Silva, F.; Campion, N.; Joaquinito, A.; Tirapicos, L.

    2015-05-01

    Since Prehistory the sky has always been integrated as part of the cosmovision of human societies. The sky played a fundamental role not only in the orientation in space, time organization, ritual practices or celestial divination but also as an element of power. Migrations and voyages are intrinsic to humankind, they opened the routes for cultural diffusion and trade, but also for power dominance. Following these routes is also to follow cultural diversity and how human societies met or clashed. The sky and astronomical phenomena provided the tools for time reckoning, calendar organization and celestial navigation that supported those voyages. Astronomy gives us today the capacity to reproduce the sky, opening a window through which we can glimpse how those societies perceived, integrated and manipulated the sky into their world-views and their myths and, ultimately, into their social organization. A voyage is always a meeting of different worlds and eventually a process to accept diversity and thus we challenged the participants of the 19th meeting of the European Society for Astronomy in Culture to present their papers in the form of a voyage or an encounter for the following topics: - Techniques of celestial navigation and orientation of the past. Astronomical navigation and nautical instruments in the XIVth, XVth and XVIth centuries; - Expressions of astronomical knowledge in architecture and monuments, rock art, archaeology and landscape. People migration, a meeting between different cultures; - History of astronomy. An encounter between different conceptions; - Astronomy and the Jesuits. A meeting between different worlds; - Astronomy in antiquity. A meeting between different knowledge; - Ethno-astronomy, Cultural Astronomy and myths, voyages in space and in time through different cultures; - To where is Archaeoastronomy voyaging? A round table about Archaeoastronomy, Cultural Astronomy and Education. The 19th meeting of the European Society for Astronomy in

  19. Estimation of a genetically viable population for multigenerational interstellar voyaging: Review and data for project Hyperion

    NASA Astrophysics Data System (ADS)

    Smith, Cameron M.

    2014-04-01

    Designing interstellar starships for human migration to exoplanets requires establishing the starship population, which factors into many variables including closed-ecosystem design, architecture, mass and propulsion. I review the central issues of population genetics (effects of mutation, migration, selection and drift) for human populations on such voyages, specifically referencing a roughly 5-generation (c. 150-year) voyage currently in the realm of thought among Icarus Interstellar's Project Hyperion research group. I present several formulae as well as concrete numbers that can be used to help determine populations that could survive such journeys in good health. I find that previously proposed such populations, on the order of a few hundred individuals, are significantly too low to consider based on current understanding of vertebrate (including human) genetics and population dynamics. Population genetics theory, calculations and computer modeling determine that a properly screened and age- and sex-structured total founding population (Nc) of anywhere from roughly 14,000 to 44,000 people would be sufficient to survive such journeys in good health. A safe and well-considered Nc figure is 40,000, an Interstellar Migrant Population (IMP) composed of an Effective Population [Ne] of 23,400 reproductive males and females, the rest being pre- or post-reproductive individuals. This number would maintain good health over five generations despite (a) increased inbreeding resulting from a relatively small human population, (b) depressed genetic diversity due to the founder effect, (c) demographic change through time and (d) expectation of at least one severe population catastrophe over the 5-generation voyage.

  20. Radiation transport of heliospheric Lyman-α from combined Cassini and Voyager data sets

    NASA Astrophysics Data System (ADS)

    Pryor, W.; Gangopadhyay, P.; Sandel, B.; Forrester, T.; Quemerais, E.; Möbius, E.; Esposito, L.; Stewart, I.; McClintock, W.; Jouchoux, A.; Colwell, J.; Izmodenov, V.; Malama, Y.; Tobiska, K.; Shemansky, D.; Ajello, J.; Hansen, C.; Bzowski, M.

    2008-11-01

    Aims: Heliospheric neutral hydrogen scatters solar Lyman-α radiation from the Sun with “27-day” intensity modulations observed near Earth due to the Sun's rotation combined with Earth's orbital motion. These modulations are increasingly damped in amplitude at larger distances from the Sun due to multiple scattering in the heliosphere, providing a diagnostic of the interplanetary neutral hydrogen density independent of instrument calibration. Methods: This paper presents Cassini data from 2003-2004 obtained downwind near Saturn at ~10 AU that at times show undamped “27-day” waves in good agreement with the single-scattering models of Pryor et al. (1992, ApJ, 394, 363). Simultaneous Voyager 1 data from 2003-2004 obtained upwind at a distance of 88.8-92.6 AU from the Sun show waves damped by a factor of ~0.21. The observed degree of damping is interpreted in terms of Monte Carlo multiple-scattering calculations (e.g., Keller et al. 1981, A&A, 102, 415) applied to two heliospheric hydrogen two-shock density distributions (discussed in Gangopadhyay et al. 2006, ApJ, 637, 786) calculated in the frame of the Baranov-Malama model of the solar wind interaction with the two-component (neutral hydrogen and plasma) interstellar wind (Baranov & Malama 1993, J. Geophys. Res., 98, 15157; Izmodenov et al. 2001, J. Geophys. Res., 106, 10681; Baranov & Izmodenov 2006, Fluid Dyn., 41, 689). Results: We conclude that multiple scattering is definitely occurring in the outer heliosphere. Both models compare favorably to the data, using heliospheric neutral H densities at the termination shock of 0.085 cm-3 and 0.095 cm-3. This work generally agrees with earlier discussions of Voyager data in Quemerais et al. (1996, ApJ, 463, 349) showing the importance of multiple scattering but is based on Voyager data obtained at larger distances from the Sun (with larger damping) simultaneously with Cassini data obtained closer to the Sun.

  1. Saturn's upper atmosphere during the Voyager era: Reanalysis and modeling of the UVS occultations

    NASA Astrophysics Data System (ADS)

    Vervack, Ronald J.; Moses, Julianne I.

    2015-09-01

    The Voyager 1 and 2 Ultraviolet Spectrometer (UVS) solar and stellar occultation dataset represents one of the primary, pre-Cassini sources of information that we have on the neutral upper atmosphere of Saturn. Despite its importance, however, the full set of occultations has never received a consistent, nor complete, analysis, and the results derived from the initial analyses over thirty years ago left questions about the temperature and density profiles unanswered. We have reanalyzed all six of the UVS occultations (three solar and three stellar) to provide an up-to-date, pre-Cassini view of Saturn's upper atmosphere. From the Voyager UVS data, we have determined vertical profiles for H2, H, CH4, C2H2, C2H4, and C2H6, as well as temperature. Our analysis also provides explanations for the two different thermospheric temperatures derived in earlier analyses (400-450 K versus 800 K) and for the unusual shape of the total density profile noted by Hubbard et al. (1997). Aside from inverting the occultation data to retrieve densities and temperatures, we have investigated the atmospheric structure through a series of photochemical models to infer the strength of atmospheric mixing and other physical and chemical properties of Saturn's mesopause region during the Voyager flybys. We find that the data exhibit considerable variability in the vertical profiles for methane, suggesting variations in vertical winds or the eddy diffusion coefficient as a function of latitude and/or time in Saturn's upper atmosphere. The results of our reanalysis will provide a useful baseline for interpreting new data from Cassini, particularly in the context of change over the past three decades.

  2. SPECTRAL EVOLUTION OF ANOMALOUS COSMIC RAYS AT VOYAGER 1 BEYOND THE TERMINATION SHOCK

    SciTech Connect

    Senanayake, U. K.; Florinski, V.; Cummings, A. C.; Stone, E. C. E-mail: vaf0001@uah.edu E-mail: ecs@srl.caltech.edu

    2015-05-01

    When the Voyager 1 spacecraft crossed the termination shock (TS) on 2004 December 16, the energy spectra of anomalous cosmic rays (ACRs) could not have been produced by steady-state diffusive shock acceleration. However, over the next few years, in the declining phase of the solar cycle, the spectra began to evolve into the expected power-law profile. Observations at the shock led to a broad range of alternative theories for ACR acceleration. In spite of that, in this work we show that the observations could be explained by assuming ACRs are accelerated at the TS. In this paper, we propose that the solar cycle had an important effect on the unrolling of the spectra in the heliosheath. To investigate the spectral evolution of ACRs, a magnetohydrodynamic background model with stationary solar-wind inner boundary conditions was used to model the transport of helium and oxygen ions. We used a backward-in-time stochastic integration technique where phase-space trajectories are integrated until the so-called “injection energy” is reached. Our simulation results were compared with Voyager 1 observations using three different diffusion models. It is shown that the spectral evolution of ACRs in the heliosheath at Voyager 1 could be explained by an increase in the source strength and an enhancement in diffusion as a result of a decrease of the turbulent correlation length in the declining phase of the solar cycle. At the same time, drift effects seem to have had a smaller effect on the evolution of the spectra.

  3. Study of dust in the vicinity of Dione using the Voyager 1 plasma wave instrument

    NASA Astrophysics Data System (ADS)

    Tsintikidis, D.; Kurth, W. S.; Gurnett, D. A.; Barbosa, D. D.

    1995-02-01

    The flyby of Voyager 1 at Saturn yielded the detection of a large variety of plasma waves, for example, chorus, hiss, and electron cyclotron harmonics. Just before the outbound equator crossing, the Voyager 1 plasma wave instrument detected a strong, well-defined low-frequency enhancement in signal levels. Initially, it was thought that this enhancement was due to plasma waves, but more recently it was suggested that dust impacts might be at least partial contributors. In this report we present evidence that dust impacts are partly responsible for the low-frequency enhancement. A new method of analysis which relies mainly on the 16-channel spectrum analyzer has been used to derive the dust impact rate. The available wideband waveform observations (which have been used previously to study dust impacts) were useful for calibrating the impact rate from the spectrum analyzer data. The mass and hence size of the dust particles were also obtained by analyzing the response of the plasma wave spectrum and analyzer. The results show that the region sampled by Voyager 1 is populated by dust particles that have rms masses of up to a few times 10-11 g and sizes of up to a few microns. The dust particle number density is of the order of 10-3/cu m. The optical depth of the region sampled by the spacecraft is approximately 10-6. The particle population is centered at 2470 (+/- 150) km south of the equatorial plane and has a north-south FWHM (full-width, half-maximum) thickness of 4130 (+/- 450) km. The dust may be part of the E ring or a localized ringlet associated with Dione.

  4. Study of dust in the vicinity of Dione using the Voyager 1 plasma wave instrument

    NASA Technical Reports Server (NTRS)

    Tsintikidis, D.; Kurth, W. S.; Gurnett, D. A.; Barbosa, D. D.

    1995-01-01

    The flyby of Voyager 1 at Saturn yielded the detection of a large variety of plasma waves, for example, chorus, hiss, and electron cyclotron harmonics. Just before the outbound equator crossing, the Voyager 1 plasma wave instrument detected a strong, well-defined low-frequency enhancement in signal levels. Initially, it was thought that this enhancement was due to plasma waves, but more recently it was suggested that dust impacts might be at least partial contributors. In this report we present evidence that dust impacts are partly responsible for the low-frequency enhancement. A new method of analysis which relies mainly on the 16-channel spectrum analyzer has been used to derive the dust impact rate. The available wideband waveform observations (which have been used previously to study dust impacts) were useful for calibrating the impact rate from the spectrum analyzer data. The mass and hence size of the dust particles were also obtained by analyzing the response of the plasma wave spectrum and analyzer. The results show that the region sampled by Voyager 1 is populated by dust particles that have rms masses of up to a few times 10(exp -11) g and sizes of up to a few microns. The dust particle number density is of the order of 10(exp -3)/cu m. The optical depth of the region sampled by the spacecraft is approximately 10(exp -6). The particle population is centered at 2470 (+/- 150) km south of the equatorial plane and has a north-south FWHM (full-width, half-maximum) thickness of 4130 (+/- 450) km. The dust may be part of the E ring or a localized ringlet assoicated with Dione.

  5. Radiation Transport of Heliospheric Lyman-alpha from Combined Cassini and Voyager Data Sets

    NASA Technical Reports Server (NTRS)

    Pryor, W.; Gangopadhyay, P.; Sandel, B.; Forrester, T.; Quemerais, E.; Moebius, E.; Esposito, L.; Stewart, I.; McClintock, W.; Jouchoux, A.; Colwell, J.; Izmodenov, V.; Malama, Y.; Shemansky, D.; Ajello, J.; Hansen, C.; Bzowski, M.

    2008-01-01

    Heliospheric neutral hydrogen scatters solar Lyman-alpha radiation from the Sun with '27-day' intensity modulations observed near Earth due to the Sun's rotation combined with Earth's orbital motion. These modulations are increasingly damped in amplitude at larger distances from the Sun due to multiple scattering in the heliosphere, providing a diagnostic of the interplanetary neutral hydrogen density independent of instrument calibration. This paper presents Cassini data from 2003-2004 obtained downwind near Saturn at approximately 10 AU that at times show undamped '27-day' waves in good agreement with the single-scattering models of Pryor et al., 1992. Simultaneous Voyager 1 data from 2003- 2004 obtained upwind at a distance of 88.8-92.6 AU from the Sun show waves damped by a factor of -0.21. The observed degree of damping is interpreted in terms of Monte Carlo multiple-scattering calculations (e.g., Keller et al., 1981) applied to two heliospheric hydrogen two-shock density distributions (discussed in Gangopadhyay et al., 2006) calculated in the frame of the Baranov-Malama model of the solar wind interaction with the two-component (neutral hydrogen and plasma) interstellar wind (Baranov and Malama 1993, Izmodenov et al., 2001, Baranov and Izmodenov, 2006). We conclude that multiple scattering is definitely occurring in the outer heliosphere. Both models compare favorably to the data, using heliospheric neutral H densities at the termination shock of 0.085 cm(exp -3) and 0.095 cm(exp -3). This work generally agrees with earlier discussions of Voyager data in Quemerais et al., 1996 showing the importance of multiple scattering but is based on Voyager data obtained at larger distances from the Sun (with larger damping) simultaneously with Cassini data obtained closer to the Sun.

  6. Spectral Evolution of Anomalous Cosmic Rays at Voyager 1 beyond the Termination Shock

    NASA Astrophysics Data System (ADS)

    Senanayake, U. K.; Florinski, V.; Cummings, A. C.; Stone, E. C.

    2015-05-01

    When the Voyager 1 spacecraft crossed the termination shock (TS) on 2004 December 16, the energy spectra of anomalous cosmic rays (ACRs) could not have been produced by steady-state diffusive shock acceleration. However, over the next few years, in the declining phase of the solar cycle, the spectra began to evolve into the expected power-law profile. Observations at the shock led to a broad range of alternative theories for ACR acceleration. In spite of that, in this work we show that the observations could be explained by assuming ACRs are accelerated at the TS. In this paper, we propose that the solar cycle had an important effect on the unrolling of the spectra in the heliosheath. To investigate the spectral evolution of ACRs, a magnetohydrodynamic background model with stationary solar-wind inner boundary conditions was used to model the transport of helium and oxygen ions. We used a backward-in-time stochastic integration technique where phase-space trajectories are integrated until the so-called “injection energy” is reached. Our simulation results were compared with Voyager 1 observations using three different diffusion models. It is shown that the spectral evolution of ACRs in the heliosheath at Voyager 1 could be explained by an increase in the source strength and an enhancement in diffusion as a result of a decrease of the turbulent correlation length in the declining phase of the solar cycle. At the same time, drift effects seem to have had a smaller effect on the evolution of the spectra.

  7. Radio occultation by Saturn's rings - Observations of structure and particle size with Voyager 1

    NASA Technical Reports Server (NTRS)

    Marouf, E. A.; Tyler, G. L.

    1985-01-01

    Voyager 1 radio occultation study of Saturn's rings gives detailed information regarding the rings' radial structure and particle sizes. Structure within the rings is mapped to a radial resolution of few hundred m in the tenuous parts of ring C and the Cassini Division, and few km over most of ring A. Fine resolution profiles reveal extremely sharp edges, very narrow gaps, and a host of wave phenomena. Particle size distributions obtained from occultation data within several ring regions are roughly consistent with an inverse cube power law with upper size cutoff in the 5 to 10 m radius range.

  8. Gravity field of the Saturnian system from Pioneer and Voyager tracking data

    SciTech Connect

    Campbell, J.K.; Anderson, J.D.

    1989-05-01

    Doppler-tracking data and star-satellite imaging from the Voyager 1 and 2 spacecraft are used along with Pioneer 11 Doppler tracking data to study the gravity field of the Saturnian system. The present analysis has yielded improved values for the masses of Rhea, Titan, and Iapetus, and Saturn. The results are consistent with the findings of Null et al. (1981) and Nicholson and Porco (1988) for the Saturn zonal harmonic coefficients J2, J4, and J6. The ratio of the mass of the sun to the mass of the Saturnian system is found to be 3497.898 + or - 0.018 30 refs.

  9. Microwave Edge Diffraction by Features in Saturn's Rings: Observations with Voyager 1.

    PubMed

    Marouf, E A; Tyler, G L

    1982-07-16

    Classical edge diffraction patterns are formed at centimeter wavelengths by several features of Saturn's rings. These patterns were discovered in 3.6-and 13-centimeter radio signals from Voyager 1 during occultation by the rings. The observed shapes are in agreement with theoretical patterns computed for screens of perfectly abrupt edges having large but finite opacity. Comparison with models in which the opacity at the edge tapers to zero from a finite value sets a new bound of less than about 200 meters on the microwave edge thickness. Certain features of the data suggest a smaller upper bound of about 130 meters on the edge thickness.

  10. Voyager 1 observations of the termination shock particles in the inner heliosheath at 122 au

    NASA Astrophysics Data System (ADS)

    Chalov, S. V.; Alexashov, D. B.

    2016-07-01

    The sharp drop in fluxes of the termination shock particles observed by Voyager 1 in the inner heliosheath at distance of about 122 au from the Sun can be explained by factors, which are not related to the heliopause crossing as is now commonly believed. It is shown that the region of the heliosheath occupied by the current sheet can be considered as a reservoir for suprathermal charged particles accelerated at the termination shock. When a spacecraft crosses the boundary of this region in the latitudinal direction, fluxes of the suprathermal particles can vary by several orders of magnitude.

  11. DISCONNECTION FROM THE TERMINATION SHOCK: THE END OF THE VOYAGER PARADOX

    SciTech Connect

    McComas, D. J.; Schwadron, N. A.

    2012-10-10

    The most recent Voyager 1 observations show rapidly increasing galactic cosmic ray fluxes with simultaneously decreasing anomalous cosmic ray fluxes. While this has been suggested to somehow herald the imminent crossing of the heliopause, which bounds the heliosphere, we show that such observations should naturally arise from the heliosphere's global magnetic topology. For a blunt termination shock, there must be a region of magnetic flux, still inside the heliopause, but beyond the last magnetic connection point to the termination shock, with poorer access for the shock-accelerated anomalous cosmic rays and better access for the galactic cosmic rays entering the heliosphere.

  12. Implications of Voyager 1 observations beyond the heliopause for the local interstellar electron spectrum

    SciTech Connect

    Bisschoff, D.; Potgieter, M. S.

    2014-10-20

    Cosmic-ray observations made by the Voyager 1 spacecraft outside the dominant modulating influence of the heliosphere finally allow the comparison of computed galactic spectra with experimental data at lower energies. These computed spectra, based on galactic propagation models, can now be compared with observations at low energies by Voyager 1 and at high energies by the PAMELA space detector at Earth. This improves understanding of basic propagation effects and also provides solar modulation studies with reliable input spectra from 1 MeV to 100 GeV. We set out to reproduce the Voyager 1 electron observations in the energy range of 6-60 MeV, as well as the PAMELA electron spectrum above 10 GeV, using the GALPROP code. By varying the source spectrum and galactic diffusion parameters, specifically the rigidity dependence of spatial diffusion, we find local interstellar spectra that agree with both power-law spectra observed by Voyager 1 beyond the heliopause. The local interstellar spectrum between ∼1 MeV and 100 GeV indicates that it is the combination of two power laws, with E {sup –(1.45} {sup ±} {sup 0.15)} below ∼100 MeV and E {sup –(3.15} {sup ±} {sup 0.05)} above ∼100 MeV. A gradual turn in the spectral shape matching the power laws is found, between 2.0 ± 0.5) GeV and (100 ± 10) MeV. According to our simplified modeling, this transition is caused primarily by galactic propagation effects. We find that the intensity beyond the heliopause at 10 MeV is (350 ± 50) electrons m{sup –2} s{sup –1} sr{sup –1} MeV{sup –1}, decreasing to (50 ± 5) electrons m{sup –2} s{sup –1} sr{sup –1} MeV{sup –1} at 100 MeV.

  13. Voyager energetic particle observations at interplanetary shocks and upstream of planetary bow shocks - 1977-1990

    NASA Technical Reports Server (NTRS)

    Krimigis, S. M.

    1992-01-01

    The Voyager 1 and 2 vehicles include instrumentation that makes comprehensive electron and ion measurements in several energy channels with good energy, temporal, and compositional resolution. Data gathered from 1977 to 1988, including observations downstream and upstream of four planetary bow shocks (earth, Saturn, Uranus, Jupiter) and numerous interplanetary shocks to about 30 AU, are analyzed in the context of the Fermi and shock drift acceleration models. Overall results indicate that electrons and ions observed upstream of planetary bow shocks have their source inside the parent magnetosphere, with first order Fermi acceleration playing a secondary role at best.

  14. Photometry from Voyager 2 - Initial results from the Neptunian atmosphere, satellites, and rings

    NASA Technical Reports Server (NTRS)

    Lane, Arthur L.; West, Robert A.; Nelson, Robert M.; Horn, Linda J.; Wallis, Brad D.; Buratti, Bonnie J.; Hord, Charles W.; Simmons, Karen E.; Pryor, Wayne R.; Esposito, Larry W.

    1989-01-01

    Voyager 2 has performed photopolarimetric measurements for the planet, several of its satellites, and its ring system. The Great Dark Spot is noted to appear as a low-albedo region, while the bright companion appear to lie at a higher altitude than the Great Dark Spot. Triton's linear phase coefficients are consistent with a solid-surface object having high reflectivity; its rotational phase curve indicates two major compositional units at its surface. The deficiency of material in Neptune's ring system by comparison with that of Uranus may indicate the absence of a recent moon-shattering event.

  15. Interstellar Dust Detected by Voyager 1 Over Heliocentric Radial Distances From 5 to 132 AU

    NASA Astrophysics Data System (ADS)

    Gurnett, D. A.; Persoon, A. M.; Granroth, L.; Kurth, W. S.

    2015-12-01

    The plasma wave instruments on the Voyager 1 and 2 spacecraft can detect the impact of high velocity dust particles when they strike the spacecraft body. The impacts are recognizable by a characteristic voltage pulse that they produce in the wideband electric field waveform data. Although the wideband receiver on Voyager 2 is no longer working, Voyager 1 has been collecting wideband data for over 37 years, starting near the Jupiter flyby at 5 AU and continuing to the most recent data beyond 132 AU. During this time a persistent level of dust impacts have been detected at a rate of about 3 to 7 impacts/ hour. We interpret these impacts as being due to interstellar dust. Using the cross-sectional area of the spacecraft high-gain antenna, 10.75 m2, as the effective impact area, and the velocity of the spacecraft relative to the 26 km/s arrival velocity of the interstellar dust, this impact rate corresponds to a flux of about (0.75 to 1.65) x 10-4 m-2 s-1. Although we do not have good knowledge of the mass of the dust particles, this flux agrees well with the interstellar dust flux published by Grün et al. [1993] from the dust detector on the Ulysses spacecraft at 5 AU. The Ulysses dust instrument showed that the mass of the interstellar dust particles ranged from about 10-15 to 10-10 grams (roughly 0.1 to 10 μm). We presume that Voyager 1 is detecting these same particles. The heliocentric radial variation can be fit within the error bars by a constant flux of about 1.2 x 10-4 m-2s-1. However, the plot of the average count rates in 20 AU bins increases steadily from 10 to 100 AU, with a notable decrease beyond 100 AU, suggesting that there might be a slightly higher flux (by a factor of two) in the outer regions of the heliosphere than in the interstellar medium.

  16. Spatial irregularities in Jupiter's upper ionosphere observed by Voyager radio occultations

    NASA Technical Reports Server (NTRS)

    Hinson, D. P.; Tyler, G. L.

    1982-01-01

    Radio scintillations (at 3.6 and 13 cm) produced by scattering from ionospheric irregularities during the Voyager occultations are interpreted using a weak-scattering theory. Least squares solutions for ionospheric parameters derived from the observed fluctuation spectra yield estimates of (1) the axial ratio, (2) angular orientation of the anisotropic irregularities, (3) the power law exponent of the spatial spectrum of irregularities, and (4) the magnitude of the spatial variations in electron density. It is shown that the measured angular orientation of the anisotropic irregularities indicates magnetic field direction and may provide a basis for refining Jovian magnetic field models.

  17. A seasonal model of the Saturnian upper troposphere Comparison with Voyager infrared measurements

    NASA Technical Reports Server (NTRS)

    Bezard, B.; Gautier, D.; Conrath, B.

    1984-01-01

    In the present extension of Cess and Caldwell's (1979) seasonal climate model to the upper troposphere of Saturn, the ring-modulated latitudinal dependence of the insolation, the ring thermal emission, the oblateness and orbital eccentricity of the planet, and the latitudinal variation of the internal heat flux, are taken into account. While these calculations agree with the temperature-latitude profiles retrieved from Voyager IRIS measurements above 0.2-bar pressure level atmospheric strata, the model fails to predict the retrieved temperature-latitude profiles below the 0.3-bar level. This discrepancy may be due to the existence of clouds at these levels.

  18. INTERPRETATION OF THE DISTURBANCE IN GALACTIC COSMIC RAYS OBSERVED ON VOYAGER 1 BEYOND THE HELIOPAUSE

    SciTech Connect

    Jokipii, J. R.; Kóta, J.

    2014-10-10

    We present a possible explanation for the transient increase in the galactic cosmic ray flux observed by Voyager 1 (V1) beyond the heliopause, in 2013 March. We suggest that this disturbance may be caused by a propagating disturbance in the interstellar magnetic field, of heliospheric origin. A model in which a magnetic disturbance, propagating outward from the heliosphere into the very-local interstellar plasma, affects the galactic cosmic rays is presented. We also discuss the possibility that this event is related to the plasma-wave event observed some 25 days later by the PWS experiment on V1.

  19. A search for Saturn electrostatic discharges in the Voyager plasma wave data

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Gurnett, D. A.; Scarf, F. L.

    1983-01-01

    A search of Voyager spacecraft plasma wave data for evidence of Saturn electrostatic discharges, whose detection was suggested to be likely on the basis of radio astronomy observations, has yielded no evidence of this phenomenon. The statistical significance of this null result is analyzed, and its ramifications are commented upon. The explanations entertained for the lack of plasma wave observations of electrostatic discharges include the possibility that many events are of much shorter duration than previously reported, or that there may be a nonlinear distortion in the radio astronomy receiver employed which may have artificially broadened the spectrum of the discharges.

  20. Phenomenology of Neptune's radio emissions observed by the Voyager planetary radio astronomy experiment

    NASA Technical Reports Server (NTRS)

    Pedersen, B. M.; Lecacheux, A.; Zarka, P.; Aubier, M. G.; Kaiser, M. L.; Desch, M. D.

    1992-01-01

    The Neptune flyby in 1989 added a new planet to the known number of magnetized planets generating nonthermal radio emissions. We review the Neptunian radio emission morphology as observed by the planetary radio astronomy experiment on board Voyager 2 during a few weeks before and after closest approach. We present the characteristics of the two observed recurrent main components of the Neptunian kilometric radiation, i.e., the 'smooth' and the 'bursty' emissions, and we describe the many specific features of the radio spectrum during closest approach.