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Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: New Insights Into Ancient Angkor By NASA Radar To Be Subject Of Press Subject: New Insights Into Ancient Angkor By NASA Radar To Be Subject Of Press Привет всем! Вот, свалилось из Internet... Douglas Isbell Headquarters, Washington, DC February 5, 1998 (Phone: 202/358-1753) Mary Hardin Jet Propulsion Laboratory, Pasadena, CA (Phone: 818/354-5011) NOTE TO EDITORS: N98-11 NEW INSIGHTS INTO ANCIENT ANGKOR BY NASA RADAR TO BE SUBJECT OF PRESS BRIEFING Radar imagery that may revolutionize archaeological understanding of the ancient Angkor complex of temples in northern Cambodia will be the subject of a NASA press briefing at 1 p.m. EST on Thursday, Feb. 12. The briefing will originate from NASA's Jet Propulsion Laboratory (JPL) in Pasadena, CA. The briefing, including supporting video material, will be broadcast live on NASA Television. Angkor is a vast complex of some 1,000 temples covering about 100 square miles of northern Cambodia, built between the 8th and 13th centuries AD. Today, much of Angkor is inaccessible or hidden beneath a dense forest canopy. The latest research findings were made possible by the Airborne Synthetic Aperture Radar (AIRSAR) developed by JPL, an Earth science instrument that can reveal features hidden from visual systems. Participants in the briefing will include: - Dr. Elizabeth Moore, Head of the Art & Archaeology Department at the School of Oriental and African Studies, University of London - JPL radar scientist Dr. Anthony Freeman NASA Television is available through GE-2, transponder 9C at 85 degrees West longitude, vertical polarization, with a frequency of 3880 Mhz, and audio at 6.8 Mhz. Journalists may ask questions in the briefing remotely at participating NASA field centers. -end- Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Space Researchers Gain Insight Into Deadly Virus Привет всем! Вот, свалилось из Internet... Michael Braukus Headquarters, Washington, DC February 5, 1998 (Phone: 202/358-1979) Steve Roy Marshall Space Flight Center, Huntsville, AL (Phone: 205/544-0034) RELEASE: 98-22 SPACE RESEARCHERS GAIN INSIGHT INTO DEADLY VIRUS NASA and industry biotechnology researchers have taken an important step toward developing a treatment for a life- threatening virus that causes pneumonia and severe upper respiratory infection in infants and young children. The infection, called Respiratory Syncytial Virus, attacks the respiratory airways and lungs. According to the National Academy of Sciences' Institute of Medicine in Washington, DC, nearly four million children ages one to five are infected every year in the United States by the virus. Approximately 100,000 of these children require hospitalization and 4,000 die annually from the resulting infection. The virus is considered by physicians to be the most serious infectious disease for infants in the United States. "Through NASA funded research in space and on the ground, and the application of space technology, we have determined the three-dimensional atomic structure of a potentially very important therapeutic antibody to this virus," said Dr. Daniel Carter, president of New Century Pharmaceuticals in Huntsville, AL. Antibodies aid the individual's immune system by neutralizing toxins, such as viruses, as they attempt to invade healthy cells. Knowledge of the molecular structure of the antibody will permit scientists to understand key interactions between the antibody and virus, facilitating development of treatments for the disease. "Currently, there is no vaccine against the virus," said Simon McKenzie, chief executive officer of Intracel Corp. in Issaquah, WA, which developed and produces the antibody. "Since this antibody neutralizes all known variants of the virus, therapeutics developed from it should have a major impact on lowering the mortality rate caused by the disease. And knowing its structure will provide key insight into our future development activities." The illness most frequently begins with a fever, up to 101 degrees Fahrenheit, along with runny nose, cough and sometimes wheezing and trouble breathing. When his six-week old daughter caught the respiratory infection, Carter saw the effects of the virus first-hand. "There was nothing the hospital could do for her," he said. "We brought her home, watched as the infection ran its course and hoped for the best," he said. His daughter recovered. Carter's research team used the viral antibody to grow antibody crystals aboard the Space Shuttle Columbia in June and July of 1997. In the weightless environment of space known as microgravity, the antibody crystals grew larger and were of better quality than those previously grown on Earth. Using highly specialized X-ray equipment and computers, scientists at New Century Pharmaceuticals located the key positions of individual atoms in the crystal structure and constructed a model of the antibody. Because of the perfection and increased size of the space-grown crystals, the researchers were able to precisely determine the atomic structure of the antibody. Dr. Arnauld Nicogossian, Associate Administrator of NASA's Office of Life and Microgravity Sciences, Washington, DC, which sponsored the joint research effort by government and industry, said, "This concrete benefit to human health is invaluable in demonstrating the importance of space-based research in solving Earth-based medical problems, as well as the need to have a permanently orbiting research facility. The International Space Station, to begin assembly later this year, will be at the forefront of new medical discoveries while it opens the space frontier to exploration." - end - Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Galileo - Countdown to Europa Привет всем! Вот, свалилось из Internet... GALILEO - COUNTDOWN TO EUROPA February 5, 1998 It is now 4 days and 22 hours to the Galileo spacecraft's next encounter with Europa. A special Countdown to Europa home page is now available on the Galileo Home Page: http://www.jpl.nasa.gov/galileo/countdown/ Launched in October 1989, Galileo entered orbit around Jupiter in December 1995, and recently completed its 2 year orbital tour around the solar system's largest planet. Galileo has now embarked on a two-year extended mission, called Galileo Europa Mission (GEM). During GEM, Galileo will make 8 close flybys of Europa, four flybys of Callisto, and two close encounters with Io provided the spacecraft is still alive. The second encounter for GEM is scheduled for Europa on February 10, 1998 at 17:57 UT. With a diameter of 3,138 km, Europa is slighty smaller than our own Moon and is the smoothest object in the solar system. On Galileo's previous encounters with Europa, evidence of a possible ocean on were found, including the discovery of ice vocalnoes (non active), probable icebergs, and salt deposits on the surface. Galileo will continue its attempt to find additional evidence of a liquid ocean underneath Europa's icy crust and look for signs of active volcanism on the moon's young surface. On the upcoming encounter, alileo will pass by Europa at a distance of 3,562 km, which is 57 times closer than Voyager's closest approach. Since this encounter occurs during solar conjunction (when the Sun is between the Earth and the spacecraft), only gravity field measurements will be made. Highlights of the Countdown to Europa home page: o A virtual flyby of Europa with computer-generated approach images displayed at the top of the home page. The page was recently expanded to included simulated Galileo views of Jupiter, Europa, Io, Callisto and Ganymede. These images are all updated every 5 minutes. o Live Doppler plots of Galileo spacecraft radio signal as it received on Earth. Watch the gravity of Europa change the frequency of the radio signal in real-time. The Doppler plots will be updated every minute on encounter day (Feb 10). o Flyby animation of the Europa 13 flyby. o The latest Galileo status reports reporting on the Europa 13 encounter. o Fact sheets and Callisto, Ganymede, Europa, Io and Amalthea. o A detailed timeline of events and sequences that the spacecraft will perform for the Europa 13 encounter. o Voyager 1 & 2 images of Callisto, Ganymede, Europa and Io. o Hubble Space Telescope images of the Galilean satellites. o Pioneer 10 & 11 images of Callisto, Ganymede, Europa and Io. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ Pasadena, CA | The truth always turns out /___| | | | ___/ | |/__ /| | to be simpler than you |_____|/ |_|/ |_____|/ | thought. Richard Feynman Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Exotic glass shows promise in low-g experiments Привет всем! Вот, свалилось из Internet... Thin fibers of an exotic glass called ZBLAN are clearer when made in near weightlessness than on Earth under gravity's effects, according to a researcher at NASA's Marshall Space Flight Center. ZBLAN glass fibers are valuable for advanced communications, medical, and manufacturing technologies using lasers. Space-based processing holds the promise of helping us understand how to make ZBLAN fibers without crystallizing, the main roadblock in their wider use today. The full story, with hi-res JPGs for print media, is at http://science.msfc.nasa.gov/newhome/headlines/msad05feb98_1.htm :) Dave Dooling Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: YES There is water on the moon! Привет всем! Вот, свалилось из Internet... Article from today's BBC: http://bbc.news.co.uk I hope you find interesting Water on the moon Conformation of the discovery should come within weeks. The BBC has been told that data sent back from the Lunar Prospector space probe suggests there is water on the moon. If this is right, then the presence of water-ice on the moon will transform the prospects for a manned lunar colony. It would be more likely that a base on the moon would be established before one on Mars. Conformation of the discovery is expected from the Lunar Prospector team within weeks. For decades, scientists have speculated that there could be up to a billion tonnes of ice buried deep in craters, where sunlight never reaches. The data sent back from the probe seems to indicate that there is water and water-ice in deep fissures near the South Pole. Lunar Prospector was launched on January 7 from Florida on an Athena rocket. The 12-month mission also involves mapping the lunar surface to determine its composition and its gravitational and magnetic fields. The total cost of the project is just under $63m, which includes the spacecraft, the science instruments, integration and test, launch and all mission operations. Lockheed Martin Missiles & Space, in Sunnyvale, California built the spacecraft. The project began as a private initiative to show that small, inexpensive missions could be developed in a short time, and still do high quality science. Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Additional Experiments Selected For Mars 2001 Missions Привет всем! Вот, свалилось из Internet... Michael Braukus Headquarters, Washington, DC January 22, 1998 (Phone: 202/358-1979) Douglas Isbell Headquarters, Washington, DC (Phone: 202/358-1753) RELEASE: 98-13 ADDITIONAL EXPERIMENTS SELECTED FOR MARS 2001 MISSIONS NASA has selected additional instruments for the Mars Surveyor 2001 missions, which will study Mars' environment. The Mars Surveyor 2001 missions will follow two other robotic Mars missions to be launched in late 1998 and early 1999. All are part of NASA's long-term, systematic exploration of Mars in which two missions are launched to the planet approximately every 26 months. "In a sense, these missions allow virtual presence by humans and provide precursor data and subsequent infrastructure for possible human missions in the 21st century," said Arnauld Nicogossian, Associate Administrator of NASA's Office of Life and Microgravity Sciences and Applications. "By adding capability to missions already planned, this near term effort will result in cost effective, tangible progress in carrying out the Human Exploration and Development of Space strategy and contribute to the Origins program of NASA's Office of Space Science." NASA's Office of Life and Microgravity Sciences and Applications has selected the following investigations for the Mars 2001 Orbiter, due for launch in March of that year, and the Mars 2001 Lander/Rover, due for launch in April 2001: * The Martian Radiation Environment Experiment will characterize the radiation environment in the orbit and on the surface of Mars simultaneously. This experiment will consist of radiation spectrometers on both the Mars 2001 Orbiter and on the Mars 2001 Lander. Dr. Guatam Badhwar from NASA's Johnson Space Center, Houston, TX, is the principal investigator. * The Mars Environmental Compatibility Assessment will characterize Martian dust and soil to identify potential undesirable and harmful interactions with human explorers and associated hardware, and to evaluate properties of the soil related to its use as a construction material. Dr. Thomas Meloy from West Virginia State University is the principal investigator. A team consisting of NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA, and Lockheed Martin Astronautics, Denver, CO, will develop the missions, led by JPL. The radiation and dust investigations were selected from 39 proposals submitted to NASA in August 1997. Both of the 2001 missions are part of an ongoing NASA series of robotic Mars exploration spacecraft that began with the launches of the Mars Global Surveyor in November 1996. The 2001 missions represent the first step in a NASA initiative to integrate the requirements for Space Science and the Human Exploration and Development of Space program into a single robotic exploration program. - end - Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: NASA Studying Space Weather From Puerto Rico Привет всем! Вот, свалилось из Internet... Donald Savage Headquarters, Washington, DC February 6, 1998 (Phone: 202/358-1547) Keith Koehler Wallops Flight Facility, Wallops Island, VA (Phone: 757/824-1579) RELEASE: 98-23 NASA STUDYING SPACE WEATHER FROM PUERTO RICO Starting Feb. 12, NASA will launch a two-month campaign in Puerto Rico to study space weather using rockets and ground instruments, including the world's largest radio telescope in Arecibo, Puerto Rico. The project is expected to provide information that ultimately will help improve the reliability of radio and satellite communications. Using a temporary range at Tortuguero on the north coast of Puerto Rico, NASA's Goddard Space Flight Center Wallops Flight Facility, Wallops Island, VA, is scheduled to launch 11 suborbital rockets between Feb. 12 and Apr. 9, 1998, as part of a project called Coqui Dos. The project is a continuation of a 1992 project called El Coqui, named after a species of native frog which is an ecological and cultural symbol of Puerto Rico. "NASA, in association with several universities and other organizations, will launch these rockets to make measurements of electrical and turbulent layers that occur in the ionosphere, approximately 62 miles above the surface of the Earth," said Miguel Larson, campaign scientist from Clemson University, SC. "People tend to think that space is a quiet place with no activity. However, over the years we have come to realize that the contrary is true," said Mike Kelley, a professor at Cornell University, Ithica, NY, and principal investigator for two of the rocket launches. In fact, the layers that are the focus of the Coqui Dos study are very active features that are responsible for disruptions of radio, television, and satellite communications. The activity is the result of the interaction between "space weather" and the Earth's atmosphere, according to Kelley, who also was the campaign scientist for NASA rocket launches from Puerto Rico in 1992. Space weather refers to the complex interactions of the Solar wind (the fast-moving stream of particles emanating from the Sun), the Sun's magnetic field and the Earth's magnetic field and atmosphere. The 1992 project had a 100 percent success rate and ten scientific papers have been published based on the data obtained, Kelley said. Just as studies of the lower atmosphere in the 1960s led to our current understanding of weather and improved weather forecasts, the Coqui Dos studies are expected to lead to a better understanding of the ionosphere so that we can predict activity in this region in the future, Kelley said. Puerto Rico was selected as the launch site due to the availability of the National Science Foundation's National Astronomy and Ionospheric Center. The Arecibo radio telescope provides unique capabilities for detecting the activity within the electrical layers. Such information is needed for both deciding when to launch the rockets and for the interpretation of the rocket measurements after the flight. The Arecibo radio telescope is the largest in the world and is an essential part of the scientific mission, Larsen said. During the Coqui Dos campaign, a total of 11 launches will be carried out as part of six separate sets of measurements. All the launches will be during the nighttime hours when ionospheric instabilities are present in the high altitude region above Puerto Rico. In some cases, two or three rocket launches may occur in one night. Five of the rockets have payloads containing small amounts of the chemical trimethyaluminum (TMA), which will be released in the ionosphere at an altitude between 50 and 93 miles altitude. When TMA is released it forms a cloud that is luminescent for 10 to 20 minutes. These clouds can be tracked visually and with camera equipment to determine where the atmospheric turbulent layers occur. The milky-white clouds should be visible within several hundred miles of the launch site, across most of Puerto Rico and perhaps on some of the neighboring islands. The harmless by-products disperse for thousands of miles before settling into the upper atmosphere. Three payloads being launched are chemical only, two payloads contain TMA and scientific instruments and six payloads contain instruments only. The rockets will be launched over the Atlantic Ocean to altitudes of from 71 to 236 miles, and will fall in the ocean beyond 30 miles off shore. The launches, which typically will occur between 7 and 11 p.m., should be visible from most of Puerto Rico, especially along the northern coast and San Juan. The flights will last approximately 10 to 15 minutes each. Further information on the Puerto Rico project, including a schedule of the rocket launches, is available on the Coqui Dos home page at: http://www.wff.nasa.gov/~web/PRCampaign/CoquiDos.html The Coqui Dos project is being conducted under the suborbital Sounding Rocket Program, which is managed at Wallops for NASA's Office of Space Science, Washington, DC. The program consists of approximately 25 sounding rockets launched each year from various locations worldwide. - end - Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Cassini Update - February 6, 1998 Привет всем! Вот, свалилось из Internet... CASSINI SIGNIFICANT EVENTS REPORT FOR WEEK ENDING 02/06/98 MSO Significant Events input for week of Friday 01/30 through Thursday 02/05: Spacecraft Status: The Cassini spacecraft is presently traveling at a speed of approximately 124,000 kilometers/hour (~77,000 mph) with respect to the Sun and has traveled approximately 281 million kilometers (~176 million miles) since launch last October 15. The most recent Spacecraft status is from the DSN tracking pass on Thursday, 02/05, over Madrid. The Cassini spacecraft is in an excellent state of health and is operating nominally, with the C6 sequence executing onboard. Inertial attitude control is being maintained using the spacecraft's hydrazine thrusters (RCS system). The spacecraft continues flying in a High Gain Antenna-to-Sun attitude. It will maintain the HGA-to-Sun attitude, except for planned trajectory correction maneuvers, for the first 14 months of flight. Communication with Earth during early cruise is via one of the spacecraft's two low-gain antennas; the antenna selected depends on the relative geometry of the Sun, Earth and the spacecraft. The downlink telemetry rate is presently 40 bps. Spacecraft Activity Summary: From Friday, 01/30, through Sunday, 02/01, there were no changes in spacecraft configuration. On Monday, 02/02, and Tuesday, 02/03, a maintenance activity was performed on the SSR Flight Software Partitions. This activity, scheduled approximately every two weeks, repairs any SSR DBEs which have occurred in the code-containing portions of the Flight Software partitions during the preceding period. Monday's activity performed the repair; Tuesday's activity read out the results of the repair and reset DBE counters in the repaired partitions. Tuesday's telemetry indicated that two DBEs were successfully repaired and one DBE was located in an unused portion of a partition (such DBEs are identified by this procedure and repaired by a different procedure). Also on Tuesday, 02/03, the Solid State Recorder (SSR) record and playback pointers were reset, according to plan. This housekeeping activity, done approximately weekly, maximizes the amount of time that recorded engineering data is available for playback to the ground should an anomaly occur on the spacecraft. On Wednesday, 02/04, and Thursday, 02/05, there were no changes in spacecraft configuration. Upcoming spacecraft events: Events for the week of 02/06 through 02/12 include: a reset of the SSR pointers (02/09), a Read-out of the Propulsion Module Subsystem (PMS) Mass Properties (02/12), in preparation for TCM-2 which is scheduled for February 25. Two science activities are being considered for the Venus 1 flyby in April. The first is a search for Venus lightning by the Radio and Plasma Wave Science instrument; the second is a check of the RADAR bounce capability. If these activities are approved, they will be added to the sequence. No off-sun-line maneuver is required. DSN Coverage: For the next month or so, there will be an increase in DSN coverage for Navigation purposes, as the second and third Trajectory Correction Maneuvers (TCMs) approach. Over the past week Cassini had 8 track periods (01/30, 01/31- 3 passes, 02/02, 02/03, 02/04, 02/05). In the coming week there will be 7 DSN passes, Friday (02/06), Sunday and Monday (02/08, 02/09), and 4 passes occurring from Tuesday through Thursday (02/10 - 01/12). Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Celestis Announces First Launch of Human Cremated Remains Into Space Привет всем! Вот, свалилось из Internet... CELESTIS 2444 Times Blvd., Suite 260 Houston, TX 77005-3253 Tel: 1 (800) 522-3217 Fax: (713) 522-7380 E-mail: Celestis@iah.com Web: http://www.celestis.com/ FOR IMMEDIATE RELEASE Celestis Announces First Launch of Human Cremated Remains into Space from the United States Interview opportunity for news media VANDENBERG AFB, CA (Feb. 7) -- Celestis, Inc., -- the Houston company that launched the cremated remains of Star Trek creator Gene Roddenberry and 1960's pop icon Timothy Leary last April from the Canary Islands -- today announced the first launch of human cremated remains from the United States is slated to occur February 9 from Vandenberg Air Force base, Lompoc, Calif. The cremated remains of 30 people will be launched aboard an Orbital Sciences Corporation Taurus (tm) rocket from Vandenberg. The vehicle's primary payloads are the U.S. Navy's Geosat Follow On (GFO) satellite, and two Orbcomm (tm) communication satellites. The Celestis paylpad was integrated onto the Taurus rocket November 20 at Orbital's facility at Vandenberg Air Force Base. Among those who will be memorialized by the flight are: -- The first woman to select the Celestis service; -- A fifteen-year-old boy from the Netherlands; -- A Japanese citizen; -- An American couple whose cremated remains are in two flight capsules located next to each other in the Celestis spacecraft, and: -- Another American couple whose cremated remains were mixed together in a single flight capsule. Celestis offers a uniquely meaningful approach to honoring and remembering family, friends, and loved ones, while simultaneously helping to open up the space frontier. The privately-funded company launches a 7-gram (0.25 oz.) sample of a person's cremated remains in a lipstick-size capsule. Each capsule, inscribed with the deceased's name and personal message, is sealed with an O-ring that securely contains the cremated remains. The company places the capsules in a honeycomb-like arrangement inside a special carrier attached to the top stage of a Taurus (tm) or Pegasus (tm) launch vehicle. Once in space, the same stage and the rocket's primary payloads separate and enter Earth orbit. Neither the capsules nor the ashes ever escape into space: The capsules remain attached to the final stage. The cremated remains launched on Celestis flights will stay on orbit between 18 months and 10 years before they re-enter the atmosphere and harmlessly vaporize. The launch is provided by Orbital Sciences Corporation of Dulles, VA., a leading provider of commercial space launch services. At a cost of $4,800 per person, Celestis services are comparrable to most conventional funeral services. The first Celestis spacecraft, launched April 21, 1997, continues to circle the Earth on an orbit inclined 30 degrees to the equator. The next Celestis spacecraft, Celestis-02, will be placed in a near-polar orbit, with an inclination of 108 degrees. "Because ours is a secondary payload on a typical commercial space mission, we will not contribute to orbital pollution," Chan Tysor, president of Celestis, said. "Eventually, the satellite will re-enter the atmosphere. . .blazing like a shooting star in final tribute." A portion of the proceeds goes to the Celestis Foundation which contributes to entrepreneurial space enterprises, educational organizations, and other charities which promote a positive future on Earth. The Foundation is supporting an ongoing fundraising effort to insure the Duth youth's participation in the flight. The teenager, an avid "Star Trek" fan, expressed his wish that his ashes be launched into space and orbit Earth just as Gene Roddenbery's had on Celestis' first flight. More information can be found on the World Wide Web at: http://utopia.knoware.nl/users/karlhh/english.htm "Space remains the domain of a few, the dream of many," said Charles Chafer, president of the Celestis Foundation. "With Celestis, the dream can finally be realized. . .a final chance to become part of the universe, by being one with the universe." The launch also has an international dimension. In addition to the Japanese and Dutch citizens on the launch, there is also a naturalized U.S. citizen who was raised and educated in Argentina. The Celestis service is evolving into a truly global service. --30-- NOTE TO EDITORS: For news media interviews, please contact Celestis' Houston office at (713) 522-7282. For press clearance to enter Vandenberg Air Force Base, journalists should call the 30th Space Wing Public Affairs Office at Vandenberg: Phone (805) 734-8232, ext. 63595, FAX (805) 734-8232, ext. 68303. Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Lunar Prospector Update - February 6, 1998 Привет всем! Вот, свалилось из Internet... Lunar Prospector Mission Status Report #17 February 06, 1998 - 6:00 pm EST (3:00 a.m. PST) As discussed in previous status reports, Lunar Prospector scientists require orbit ephemeris data that describe the position of the spacecraft over the moon in order to accurately map data collected by their instruments onto the lunar surface. An accurate history of the Lunar Prospector trajectory over the moon is referred to as a "definitive" orbit ephemeris. Predictions of the future path of the spacecraft is referred to as a "predicted" orbit ephemeris. For Lunar Prospector, engineers at NASA's Goddard Space Flight Center use Doppler data collected by tracking stations from the Jet Propulsion Laboratory's (JPL) Deep Space Network to compute a definitive orbit ephemeris. Predicted orbit ephemeredes are also generated for several weeks into the future in order to enable mission controllers to schedule station tracks, anticipate shadow events and plan orbit maneuvers as necessary. Long-term predictions of the path of low altitude lunar orbiting missions is made difficult by the moon's non-uniform gravity field that results from an uneven distribution of the moon's mass. The non-uniform mass distribution of the moon makes it necessary to construct complicated models of the lunar gravity in order to accurately predict the evolution of the LP orbit over time. The figure below shows predictions made shortly after entering the mapping orbit of the periapsis (lowest) and apoapsis (highest) altitude of Lunar Prospector compared with actual values computed from a definitive orbit. Such figures are used to assess the accuracy of candidate lunar gravity models The Doppler Gravity Experiment (see description under the "Instrument" heading of the LP Web site's Science section) conducted by Dr. Alexander Konopliv of JPL, will among other things, help construct an improved gravity model of the moon which can be used by this and future missions to compute accurate long-term orbit predictions. Until now, very few missions have orbited the moon close enough and long enough to allow a highly accurate lunar gravity model to be constructed. Lunar Prospector is unique, in that it will orbit the moon in a low polar orbit (dropping as low as 10 km during the extended mission) that will provide gravity data over the entire lunar surface every two weeks. Already, preliminary gravity models from the Doppler Gravity Experiment are being generated which appear to be tracking definitive solutions much more closely than the sample pre-launch model shown in the figure below. Hа сегодня все, пока! =SANA=

Дата: 08 февраля 1998 (1998-02-08) От: Alexander Bondugin Тема: Mars Surveyor 98 Update - February 6, 1998 Привет всем! Вот, свалилось из Internet... 1998 Mars Surveyor Project Status Report February 6, 1998 John McNamee Mars Surveyor 98 project Manager Orbiter and lander integration and test activities are proceeding on schedule with no significant problems. The Mars Volatile and Climate Surveyor (MVACS) payload integration and functional checkout on the lander spacecraft is complete. The flight Surface Stereo Imager (SSI), Meteorology package (MET), Robotic Arm (RA), Robotic Arm Camera (RAC), and engineering model Thermal and Evolved Gas Analyzer (TEGA) are installed on the lander. A data transfer problem was found in the SSI instrument and the lander Command and Data Handling Subsystem interface. The SSI electronics card is being modified to resolve the discrepancy. The flight Mars Descent Imager (MARDI) instrument will be installed on the lander on February 10 completing the lander payload integration activities until the flight TEGA is available for installation. For more informaton on the Mars Surveyor 98 mission, please visit the Mars Surveyor 98 home page: http://mars.jpl.nasa.gov/msp98/ Hа сегодня все, пока! =SANA=

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