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Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Освещение метеорного потока Леонид в Internet Привет всем! Вот, свалилось из Internet... Освещение метеорного потока Леонид в Internet [NASA] Связь между появлением кометы Темпеля-Таттла и следующим за ним через 10 месяцев метеорным потоком Леонид была замечена в 1865 г. (сам поток наблюдался в 1866 г.). В нынешнем 1998 г. ожидается, что поток Леонид будет иметь самую высокую в этом столетии интенсивность. Его пик придется на ночь с 16 на 17 ноября. Лучше всего это явление будет видно в районах Восточной Азии и в западной части Тихого океана, но и в остальных частях света можно будет увидеть 20-40 метеоров в час. Вот несколько адресов в Internet, где можно будет ознакомиться с информацией об этом грандиозном астрономическом явлении: 1) Web-узел Королевской Гринвичской обсерватории The Leonids-RGO: http://www.ast.cam.ac.uk/RGO/leaflets/solar_system/leonids.html 2) Специальная Web-страница сервера NASA - Leonid '98 Meteor Outburst Page, где будут представлены данные о потоке Леонид, полученные с помощью разнообразного оборудования, установленного на борту специального самолета, который поднимется в воздух во время прохождения Земли через поток Леонид. Здесь также представлена история наблюдения этого метеорного потока. Планируется публиковать новости и полученные изображения. http://www-space.arc.nasa.gov/~leonid/ 3) Hа узле Live! Leonids 98 (http://www.leonids.net/live/) 17 ноября будет вестись "прямой репортаж" о прохождении потока Леонид в формате RealPlayer, в последующие несколько дней здесь будут размещаться выборочные изображения метеорного потока. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Астрономы всего мира готовы к наблюдению метеорного потока... Привет всем! Вот, свалилось из Internet... Астрономы всего мира готовы к наблюдению метеорного потока Леонид и ... к защите от него [SpaceViews] Леонид - это один из метеорных потоков, через которые Земля пролетает каждый год, он представляет собой хвост кометы Темпеля-Таттла (Tempel-Tuttle). Его интенсивность достигает максимума каждый год 17-18 ноября, но только раз в 33 года он бывает особенно сильным, и именно в такие моменты имеет смысл говорить о метеорном дожде. Последний раз это явление наблюдалось в 1966 г. И вот - новое пришествие. Пик метеорного дождя, когда в течение часа можно будет увидеть тысячи вспыхивающих в земной атмосфере метеорных частиц, можно будет наблюдать на территории от Дальнего Востока до Центральной Азии. NASA будет вести наблюдения с двух самолетов, которые будут летать над территорией Японии. Hа борту этих самолетов установлено самое разнообразное оборудование, в том числе и для улавливания органических молекул в метеорных частицах, что позволит прояснить картину возникновения жизни на Земле, то есть определить, как космические частицы могли способствовать появлению на Земле соответствующих условий для зарождения жизни. В то время как астрономы готовятся к наблюдениям, центры управления полетами околоземных спутников принимают меры для защиты своих орбитальных объектов от возможных повреждений метеорами. Хотя метеоры очень малы, но во время метеорного дождя их бывает очень много и скорость их составляет порядка 72 км/с. Большой ущерб могут нанести не сами метеоры (дырку в спутнике они проделать не смогут), а вторичные эффекты от их ударов. Скорость их так велика, что частица поверхности попавшегося на пути объекта будет испаряться с образованием плазмы, то есть ионизованных частиц, электромагнитные поля которых могут вывести из строя чувствительное электронное оборудование, установленное на спутнике. Именно из-за таких явлений в 1993 г. Европейское Космическое Агентство потеряло свой спутник после прохождения метеорного потока Персеид. Центры управления постараются таким образом ориентировать спутники, чтобы минимизировать количество попадаемых в них метеорных частиц. Большинство спутников будут непрерывно вести свою работу, но на некоторых аппаратура будет выключена, в частности на Rossi X-Ray Timing Explorer. Космический телескоп Hubble Space Telescope будет повернут таким образом, чтобы в его зеркала не попадали метеорные частицы, соответствующим образом будут установлены и панели солнечных батарей. Однако наблюдения на телескопе не будут останавливаться. Станция "Мир" продолжит свою работу во время прохождения потока Леонид. Hа прошлой неделе во время последнего своего выхода в открытый космос Геннадий Падалка и Сергей Авдеев установили на ее внешней поверхности специальный российско-французский датчик-ловушку космических частиц. Во время максимальной интенсивности метеорного потока космонавты на всякий случай будут находится в спускаемом модуле, чтобы в случае возникновения на станции нештатных ситуаций вернуться на Землю. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Подготовка к старту ракеты-носителя "Протон" Привет всем! Вот, свалилось из Internet... Подготовка к старту ракеты-носителя "Протон" Сегодня утром на космодроме "Байконур" началась подготовка к старту ракеты носителя "Протон", которая должна вывести на орбиту первый элемент Международной космической станции - управляющий модуль "Заря" (на снимке). Запуск состоится в ранее намеченное время - 20 ноября 1998 г. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Presentation At Pueblo Weisbrod Aircraft Museum Привет всем! Вот, свалилось из Internet... Who: The Pueblo Weisbrod Aircraft Museum and Home of the International B-24 Museum What: will present a lecture by Dr. Boyd Baldauf (ED.D) former Professor of Computer Science at the University of Southern Colorado and Colonel USAFR (Retired) titled: _Looking at Earth From Space, Listening to Deep Space_. Topics covered will be military and civilian uses of space, improving imagery from space, and the Search for Extraterrestrial Intelligence (SETI). Where: The museum is located at the Pueblo Memorial Airport 31001 Magnuson Ave, Pueblo, Colorado 81001. The airport is located approximately 5 miles east of Pueblo on US Highway 50 E/Colorado State Highway 96 East. When: The presentation will be on 21 November 1998 at 2:00 PM. Additional information: Admission is free. A recommended donation of $3 for adults (persons 12 years and greater) is appreciated but not required. No one will be turned away. All donations go toward the museum building fund. Contact the museum at (719)948-9219 or email at pwam@usa.net for more information. Jason Unwin Volunteer Pueblo Weisbrod Aircraft Museum Home of the International B-24 Museum Pueblo, CO 81001 (719)948-9219 Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Zarya Briefings And Launch Coverage Set Привет всем! Вот, свалилось из Internet... Debra J. Rahn Headquarters, Washington, DC November 16, 1998 (Phone: 256-961-6226 - Russian 586-75-60) Kyle Herring NASA Moscow Office (Phone: 256/961-6225 - Russian 586-75-60) NOTE TO EDITORS: N98-69 ZARYA BRIEFINGS AND LAUNCH COVERAGE SET The launch of the first component of the new International Space Station, the Russian-built, U.S.-owned Zarya Control Module, will be the subject of a preflight briefing at the Russian Mission Control Center in Korolev, Russia, outside Moscow, at 8 a.m. EST ( 4:00 p.m. Moscow time) on Nov. 17. The news conference will take place just three days before Zarya is scheduled to be launched atop a Russian Proton rocket from the Baikonur Cosmodrome in Kazakstan. The news conference will be broadcast live on NASA Television, but questions can only be asked by reporters at the Russian Mission Control Center. The participants will include: Gretchen McClain, Deputy Associate Administrator for Space Station Randy Brinkley, International Space Station (ISS) Program Manager Mikhail Sinelchikov, Director of Piloted Programs, Russian Space Agency Alain Poirier, Director General, Space Systems, Canadian Space Agency Frank Longhurst, Head, Manned Spaceflight Program, European Space Agency Tsuguo Tadakawa, Deputy Director, Space Utilization Promotion Dept., National Space Development Agency of Japan Two days later, on Nov. 19, video of the final prelaunch preparations for Zarya and the rollout of the Proton rocket to its launch pad at Baikonur will be presented on the NASA TV Video File at noon EST. Based on Zarya's current planned launch time of 1:40 a.m. EST (9:40 a.m. Moscow time, 11:40 a.m. Baikonur time,) on Nov. 20, NASA public affairs commentary and live television coverage of the countdown and the launch will begin at 1:10 a.m. EST (9:10 a.m. Moscow time). A postlaunch news conference will be held at Baikonur with senior level officials approximately two hours after launch. It is expected to be broadcast live on NASA Television with questions from reporters at Baikonur. A second postlaunch news conference will be held at the Russian Mission Control Center following the Baikonur conference to give a technical status report on Zarya. It will be broadcast live on NASA TV with questions from reporters in Moscow. Written status reports on Zarya's operation in orbit will be issued on subsequent days addressing major activation events leading up to the launch of the Unity connecting module aboard Endeavour on the first shuttle assembly mission, STS-88, on December 3. Following the STS-88 mission, with Zarya and Unity mated as the first Space Station elements, written status reports and status briefings on the unpiloted flight of the International Space Station will be provided periodically. Note: News media planning to attend the news conferences or the Zarya launch from the Russian Mission Control Center, Korolev, who are not already accredited, should request press accreditation from the Russian press office at 011-7-095-187-2344, or by calling the NASA public affairs office in Moscow at 256-961-6225, 6226, or Russian line 586-75-60. -end- NASA press releases and other information are available automatically Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Encouraging Report On The Leonids Привет всем! Вот, свалилось из Internet... Forwarded From George Zay (GeoZay@aol.com) Subject: Leonid fireballs galore! Nov 15/16 ZAYGE Meteor/Leonid observations for the night of Nov 15/16, 1998 From Descanso, California, San Diego County I just got back from the best meteor shower I've ever witnessed. I observed from my descanso, calif. observatory under clear skies with bob lunsford. I have a teff of about 7.5 hours and an LM near 6.0 for most of the night. I plotted until about midnight and then just record data without plotting. I recorded a total of 140 meteors. 77 were leonids, 31 N. Taurids, 2 S. Taurids and 30 sporadics. But!! out of the 77 leonids I recorded 25 fireballs. I also recorded a brilliant N. Taurid fireball with a magnitude of -12. I thought that was gonna be the highlight of the night...but it didn't even come close. The magnitudes of the leonid fireballs are as follows: -3,-3,-3,-3,-3, -4,-4,-4,-4, -5,-5,-5, -6,-6,-6,-6, -7,-7,-7, -8,-8, -10, -12, -12, -15 The trains lasted quite long for a lot of them. One -7 had a train last 30 seconds, then the other two -7's had trains lasting over 100 seconds each, one of the -8's train lasted over 100 seconds as well. The -10 had a train last 4.5 minutes and the -15 train lasted over 8 minutes. The -15 and a -12 had persistent trains that were of magnitudes of around -8 for a few seconds it seemed. They snaked and twisted all over the place. It was hard to keep count of their durations because often another fireball would show up. The -15 occurred above and behind us...the stars totally disappeared and the sky looked like daylight blue for a second or two. It was pure old excitement. I wanted to go to the bathroom, but didn't dare because I was afraid I would miss another fireball. The strange thing about last nights activity, there were very little dim meteors...that is those that were of around +3 or dimmer. Besides the fireballs, I also recorded three that had magnitudes of -2 and 8 were of -1 magnitudes. I won't have time to do my report for a few days...but I bet my mean magnitude will be around -3 or more? Never had this happen before. We were caught completely off guard for this kind of activity the night before the leonid maximum. I hope to be out there again tonight for the leonid maximum...if the weather holds out? Now to get some shut eye...I might have to do a road trip to an area in the desert near Yuma, arizona if that front comes down like it might...got my toes crossed. George Zay Descanso, California Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Weiler Named NASA's Associate Adminstrator For Space Science Привет всем! Вот, свалилось из Internet... Douglas Isbell/Don Savage Headquarters, Washington, DC November 16, 1998 (Phone: 202/358-1547) RELEASE: 98-204 WEILER NAMED ASSOCIATE ADMINISTRATOR FOR SPACE SCIENCE NASA Administrator Daniel S. Goldin today named Dr. Edward J. Weiler as Associate Administrator for NASA's Office of Space Science, effective immediately. Weiler has served as acting Associate Administrator since Sept. 28, following the departure of Dr. Wesley T. Huntress, Jr. "In his short time as acting Associate Administrator, Ed Weiler has demonstrated both the management skills and scientific leadership that this position demands, and I am delighted he has accepted the offer on a more permanent basis," Goldin said. In this capacity, Weiler will be responsible for providing overall executive leadership of NASA's Space Science Enterprise. This enterprise aims to achieve a comprehensive understanding of the origins and evolution of the Solar System and the Universe, including connections between the Sun and the Earth, the beginnings of life and the question of whether life exists elsewhere beyond Earth. It also is charged with communicating this knowledge to the public. Weiler was appointed as Science Director of the Astronomical Search for Origins and Planetary Systems theme within the Office of Space Science in March 1996. He will continue to serve as the Program Scientist for the Hubble Space Telescope, a position he has held since 1979, until a replacement for that position is selected. Weiler joined NASA in 1978 as a staff scientist. Prior to that, Weiler was a member of the Princeton University research staff and was based at NASA'S Goddard Space Flight Center, Greenbelt, MD, as the director of science operations of the Orbiting Astronomical Observatory-3 (COPERNICUS). Weiler received his Ph.D. in astrophysics from Northwestern University in January 1976. Weiler lives in Bowie, MD, and has two children, Gregory, 9, and Allison, 12. -end- Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Third US Space Station Assembly Crew Named Привет всем! Вот, свалилось из Internet... Jennifer McCarter Headquarters, Washington, DC November 16, 1998 (Phone: 202/358-1639) Doug Peterson Johnson Space Center, Houston, TX (Phone: 281/483-5111) RELEASE: 98-205 THIRD U.S. SPACE STATION ASSEMBLY CREW NAMED Astronaut James D. Halsell, Jr. (Lieutenant Col., USAF) will command the third Space Shuttle mission to carry cargo to space for the International Space Station in August 1999. Joining Halsell in the flight deck for mission STS-101 aboard Atlantis will be Pilot Scott J. Horowitz, Ph.D. (Lieutenant Col., USAF). Rounding out the crew are Mission Specialists Mary Ellen Weber, Ph.D.; Edward Tsang Lu, Ph.D.; and Jeffrey N. Williams (Lieutenant Col., USA). As the third International Space Station assembly flight, the mission will carry internal logistics and resupply cargo for station operations. The equipment will further the outfitting of the Russian Service Module. "STS-101 will bring important components and equipment to the growing Station assembly," said James D. Wetherbee, Director of Flight Crew Operations and Deputy Director of NASA's Johnson Space Center, Houston. "This talented crew brings a great deal of experience and skill to make this key mission a success." STS-101 will be Halsell's fifth mission, and his third as commander. Selected as an astronaut in 1990, he flew as pilot on STS-65 in 1994 and STS-74 in 1995, and as commander on STS-83 and STS-94 in 1997. Horowitz served as pilot in his two previous missions: STS-75 in 1996 and STS-82 in 1997. Weber, a Mission Specialist onboard Discovery on STS-70, will be on her second space flight. Lu also will be on his second space trip; his first was STS-84 which docked to the Mir Space Station. Mission Specialist Williams will be making his first space flight. For biographical information on the STS-101 crew and other astronauts, see the NASA Internet astronaut biography home page at: http://www.jsc.nasa.gov/Bios/ For information on the International Space Station, visit the Space Station home page at: http://station.nasa.gov/ - end - Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: STARDUST Update - November 13, 1998 Привет всем! Вот, свалилось из Internet... STARDUST Status Report November 13, 1998 Ken Atkins STARDUST Project Manager I hope you've noticed from the picture on the homepage we are now sending them live from Kennedy Space Center (KSC) in Florida: http://stardust.jpl.nasa.gov/webcam The spacecraft was packed into its shipping container last week and this week was transported by truck to Buckley Field in Denver. There, it was carefully loaded aboard a giant USAF C-17 jet transport and flown to KSC aboard a USAF C-17. It arrived at 2:00 am on November 12 and was moved to the Payload Hazardous Servicing Facility (PHSF) for check-out, some re-installation of electronics and beginning preparations for mating to the Delta II launch rocket. The spacecraft has been set up on its handling dolly and the solar arrays, high-gain antenna removed and the bottom panel removed for access to the interior. A crew filmed the whole delivery process and KSC released 15 news photos of STARDUST's arrival at KSC. These have been merged with the JPL press release and are available now on the web site. We also now have a time lapse movie of the unpacking sequence at KSC. All this great action is found at: http://stardust.jpl.nasa.gov/news/news39.html. With the arrival at KSC, I understand NASA will be showing some of the footage on NASA TV. Hope you can catch it there too. Speaking of pictures, now that STARDUST is at KSC the still images of activities in the PHSF are back on line. The image is updated every minute with the last 10 images available at any time. http://stardust.jpl.nasa.gov/spacecraft/construction.html For more information on the STARDUST mission - the first ever comet sample return mission - please visit the STARDUST home page: http://stardust.jpl.nasa.gov Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: The Leonid Sample Return Mission Привет всем! Вот, свалилось из Internet... The Leonid Sample Return Mission NASA scientists will try to capture and return a Leonid meteoroid http://science.nasa.gov/newhome/headlines/ast16nov98_3.htm November 16, 1998: High above the clouds on November 17th a NASA weather balloon will lie in wait for the Leonid meteors. The goal: to capture a meteoroid and return it to Earth intact. "The chances of success are small, probably less than 10%", says Dr. David Noever, the project leader at NASA's Marshall Space Flight Center, "but of course the payoff is rather huge." One of the goals of the experiment is to see if the "Stuff of Life" -- organic compounds and other molecules -- are present in the debris of comet Tempel-Tuttle, the source of the Leonid meteoroids. Amino acids and other organic molecules necessary for life as we know it on Earth are thought to be common in meteorites and comets. While life probably doesn't thrive inside comets, the compounds they carry might have contributed to the genesis of life on Earth billions of years ago. Scientists would like to know whether the comet, which passed Earth just last January, contains organic compounds, and if organic molecules are created when a Leonid meteor burns up in Earth's atmosphere. To answer these questions researchers from the Marshall Space Flight Center hope to capture a piece of the comet Tempel-Tuttle. Tuesday's meteor storm is like "room service for science", says Dr. David Noever, a member of the Astrobiology Institute. "Instead of us going to the comet, it's coming to us." Scientists will use a particle collector made of aerogel carried aloft on a helium-filled weather balloon. Weather permitting, the balloon is scheduled for launch from the Marshall Space Flight Center at 2 am Central Standard Time on November 17th . The payload will include a meteoroid collection device, and a CCD video camera. The balloon will spend up to 4 hours aloft and reach a maximum altitude of 100,000 ft. High above the clouds and far away from city lights the view could be spectacular. Live video from the flight will be available to the public at Leonids Live! (http://www.leonidslive.com) in RealVideo format beginning approximately 0800 UT November 17th (0200 CST). Video and images from the NASA's East Asia plane flights will also be posted at that web site. Aerogel is the lightest known solid, and is considered the best substance available for capturing fragile particles from a comet without damaging them. When a high-velocity dust particle hits the aerogel, it buries itself in the material, creating a carrot-shaped track up to 200 times its own length. Since aerogel is translucent scientists can use these tracks to find the tiny particles. The track is largest at the point of entry, and the particle can be collected intact at the point of the cone. The sample collector on tomorrow's balloon mission will consist of twenty-four 1" diameter circular wells of aerogel films clustered in a 6"x4" payload. The aerogel has a mean density around 0.08 g/cc and is semitransparent. The total weight is less than a few ounces (mainly container and structural supports, not aerogel), so it should have a negligible effect on the flight of the balloon. According to Dr. David Noever, "The drawback I see is that we are forced to catch everything from ground to 100,000 feet, mainly because we do not have time to fashion a remote control door that opens or closes to expose the capture media. This experiment should be considered an engineering test, and we'll make improvements prior to the 1999 Leonid shower." Prelude to Stardust The Leonids Return Mission is an interesting prelude to another NASA mission with possible connections to Astrobiology: the Stardust Mission. Stardust is a spacecraft, scheduled for launch in early 1999, designed to collect and return to Earth particles flying off the nucleus of Comet Wild-2 in January 2004. It will also bring back samples of interstellar dust including the recently discovered dust streaming into the solar system from other stars. The spacecraft will count the comet particles striking the spacecraft, and produce real-time analyses of the composition of the material coming off the comet. Like the Leonids balloon flight, Stardust will use an aerogel-based collector to capture bits of the comet. "The transparency of aerogel is critical to the success of Stardust; tracing particle tracks by eye or microscope requires a reasonably clear material", explained David Noever. Aerogel made on earth is not perfectly transparent because of irregularities in the pores which permeate the substance (aerogel is 99% empty space). There is some evidence that aerogels manufactured in low gravity are much clearer, and an experiment was just conducted on space shuttle mission STS-95 to test the idea. "Space-manufactured aerogels could significantly improve our ability to capture comet particles," commented David Noever. "Using centrifuges we can make aerogel with a density gradient: low density on one side for low damage particle capture, backed by a denser section to insure nothing escapes out the other side. This kind of thin-to-dense aerogel is unique in this dust capture business and may be unique to the way we make aerogel in space. It's an open question at the moment." When Stardust swings by Earth in January 2006, the aerogel samples encased in a reentry capsule will be jettisoned and parachute to a pre-selected site in the Utah desert. Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: 1998 Mars Orbiter, Lander, Microprobes Set For Launch Привет всем! Вот, свалилось из Internet... 1998 MARS ORBITER, LANDER, MICROPROBES SET FOR LAUNCH November 1998 NASA embarks on a return trip to Mars this winter with two spacecraft launches that will first send an orbiter to circle the red planet, then follow with another to land on the frigid, barren steppe near the edge of Mars' south polar cap. Piggybacking on the lander will be two small probes that will smash into the Martian surface to test new technologies. Mars Climate Orbiter, scheduled for launch Dec. 10, and Mars Polar Lander, scheduled for launch Jan. 3, will seek clues to the history of climate change on Mars. Both will be launched atop identical Delta II launch vehicles from Launch Complex 17 A and B at Cape Canaveral Air Station, FL, carrying instruments to map the planet's surface, profile the structure of the atmosphere, detect surface ice reservoirs and dig for traces of water beneath Mars' rusty surface. The lander also carries a pair of basketball-sized microprobes that will be released as the lander approaches Mars and dive toward the planet's surface, penetrating up to about 1 meter (3 feet) underground to test 10 new technologies, including a science instrument to search for traces of water ice. The microprobe project, called Deep Space 2, is part of NASA's New Millennium Program. The missions are the second installment in NASA's long-term program of robotic exploration of Mars, which was initiated with the 1996 launches of the currently orbiting Mars Global Surveyor and the Mars Pathfinder lander and rover. The 1998 missions will advance our understanding of Mars' climate history and the planet's current water resources by digging into the enigmatic layered terrain near one of its poles for the first time. Instruments onboard the orbiter and lander will analyze surface materials, frost, weather patterns and interactions between the surface and atmosphere to better understand how the climate of Mars has changed over time. Key scientific objectives are to determine how water and dust move about the planet and where water, in particular, resides on Mars today. Water once flowed on Mars, but where did it go? Clues may be found in the geologic record provided by the polar layered terrain, whose alternating bands of color seem to contain different mixtures of dust and ice. Like growth rings of trees, these layered geological bands may help reveal the secret past of climate change on Mars and help determine whether it was driven by a catastrophic change, episodic variations or merely a gradual evolution in the planet's environment. Today the Martian atmosphere is so thin and cold that it does not rain; liquid water does not last on the surface, but quickly freezes into ice or evaporates and resides in the atmosphere. The temporary polar frosts which advance and retreat with the seasons are made mostly of condensed carbon dioxide, the major constituent of the Martian atmosphere. But the planet also hosts both water-ice clouds and dust storms, the latter ranging in scale from local to global. If typical amounts of atmospheric dust and water were concentrated today in the polar regions, they might deposit a fine layer every year, so that the top meter (or yard) of the polar layered terrains could be a well-preserved record showing 100,000 years of Martian geology and climatology. Nine and a half months after launch, in September 1999, Mars Climate Orbiter will fire its main engine to put itself into an elliptical orbit around Mars. The spacecraft will then skim through Mars' upper atmosphere for several weeks in a technique called aerobraking to reduce velocity and circularize its orbit. Friction against the spacecraft's single, 5.5-meter-long (18-foot) solar array will slow the spacecraft as it dips into the atmosphere each orbit, reducing its orbit period from more than 14 hours to 2 hours. Finally, the spacecraft will use its thrusters to settle into a polar, nearly circular orbit averaging 421 kilometers (262 miles) above the surface. From there, the orbiter will await the arrival of Mars Polar Lander and serve as a radio relay satellite during the lander's surface mission. After the lander's mission is over, the orbiter will begin routine monitoring of the atmosphere, surface and polar caps for a complete Martian year (687 Earth days), the equivalent of almost two Earth years. The orbiter carries two science instruments: the Pressure Modulator Infrared Radiometer, a copy of the atmospheric sounder on the Mars Observer spacecraft lost in 1993, and the Mars Color Imager, a new, light-weight imager combining wide-and medium-angle cameras. The radiometer will measure temperatures, dust, water vapor and clouds by using a mirror to scan the atmosphere from the Martian surface up to 80 kilometers (50 miles) above the planet's limb. Meanwhile, the imager will gather horizon-to-horizon images at up to kilometer-scale (half-mile-scale) resolutions, which will then be combined to produce daily global weather images. The camera will also image surface features and produce a map with 40-meter (130-foot) resolution in several colors, to provide unprecedented views of Mars' surface. Mars Polar Lander, launched a month after the orbiter is on its way, will arrive in December 1999, two to three weeks after the orbiter has finished aerobraking. The lander is aimed toward a target sector within the edge of the layered terrain near Mars' south pole. The exact landing site coordinates will be adjusted as late as August 1999, based on images and altimeter data from the currently orbiting Mars Global Surveyor. Like Mars Pathfinder, Mars Polar Lander will dive directly into the Martian atmosphere, using an aeroshell and parachute scaled down from Pathfinder's design to slow its initial descent. The smaller Mars Polar Lander will not use airbags, but instead will rely on onboard guidance and retro-rockets to land softly on the layered terrain near the south polar cap a few weeks after the seasonal carbon dioxide frosts have disappeared. After the heat shield is jettisoned, a camera will take a series of pictures of the landing site as the spacecraft descends. As it approaches Mars about 10 minutes before touchdown, the lander will release the two Deep Space 2 microprobes. Once released, the projectiles will collect atmospheric data before they crash at about 200 meters per second (400 miles per hour) and bury themselves beneath the Martian surface. The microprobes will test the ability of very small spacecraft to deploy future instruments for soil sampling, meteorology and seismic monitoring. A key instrument will draw a tiny soil sample into a chamber, heat it and use a miniature laser to look for signs of vaporized water ice. About 100 kilometers (60 miles) away from the microprobe impact sites, Mars Polar Lander will dig into the top of the terrain using a 2-meter-long (6-1/2-foot) robotic arm. A camera mounted on the robotic arm will image the walls of the trench, viewing the texture of the surface material and looking for fine-scale layering. The robotic arm will also deliver soil samples to a thermal and evolved gas analyzer, an instrument that will heat the samples to detect water and carbon dioxide. An onboard weather station will take daily readings of wind temperature and pressure, and seek traces of water vapor. A stereo imager perched atop a 1.5-meter (5-foot) mast will photograph the landscape surrounding the spacecraft. All of these instruments are part of an integrated science payload called the Mars Volatiles and Climate Surveyor. Also onboard the lander is a light detection and ranging (lidar) experiment provided by Russia's Space Research Institute. The instrument will detect and determine the altitude of atmospheric dust hazes and ice clouds above the lander. Inside the instrument is a small microphone, furnished by the Planetary Society, Pasadena, CA, which will record the sounds of wind gusts, blowing dust and mechanical operations onboard the spacecraft itself. The lander is expected to operate on the surface for 60 to 90 Martian days through the planet's southern summer (a Martian day is 24 hours, 37 minutes). The mission will continue until the spacecraft can no longer protect itself from the cold and dark of lengthening nights and the return of the Martian seasonal polar frosts. The Mars Climate Orbiter, Mars Polar Lander and Deep Space 2 missions are managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, DC. Lockheed Martin Astronautics Inc., Denver, CO, is the agency's industrial partner for development and operation of the orbiter and lander spacecraft. JPL designed and built the Deep Space 2 microprobes. JPL is a division of the California Institute of Technology, Pasadena, CA. Hа сегодня все, пока! =SANA=

Дата: 17 ноября 1998 (1998-11-17) От: Alexander Bondugin Тема: Galileo - Countdown To Europa Привет всем! Вот, свалилось из Internet... GALILEO - COUNTDOWN TO EUROPA November 16, 1998 It is now 5 days and 10 hours to the Galileo spacecraft's next encounter with Europa. A special Countdown to Europa home page is 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 completed its primary 2 year orbital tour around the solar system's largest planet. Galileo has 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 seventh encounter for GEM is scheduled for Europa on November 22, 1998 at 11:47 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 were found, including the discovery of ice volcanoes (none 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, the spacecraft will pass by Europa at a distance of 2,281 km, which is over 320 times closer than Voyager's closest approach. Galileo will also take in observations of Jupiter, Io and Ganymede. Highlights of the Countdown to Europa home page: o A virtual flyby of Europa with computer-generated approach images of Jupiter and Europa displayed at the top of the home page. These images are all updated every 5 minutes. o Flyby animation of the Europa 18 flyby. o Daily Galileo status reports reporting on the Europa 18 encounter. o Fact sheets and Europa, Callisto and Io. o A detailed timeline of events and sequences that the spacecraft will perform for the Europa 18 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 Galileo Webmaster Hа сегодня все, пока! =SANA=

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