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Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: Ионный двигатель на Deep Space 1 проработал недолго Привет всем! Вот, свалилось из Internet... Ионный двигатель на Deep Space 1 проработал недолго [SpaceViews] Ионный двигатель, установленный на экспериментальном космическом корабле Deep Space 1 (DS1) выключился через 4,5 минуты после начала работы (10 ноября 1998 г., 14:30 по восточному поясному времени). Причина остановки двигателя пока не известна, попытки его повторного запуска остались безуспешными. "Выключения" ионного двигателя уже наблюдались при испытаниях на Земле и на космическом корабле на околоземной орбите, но DS1 предназначается для дальних космических экспедиций. Испытания такого двигателя в дальнем космосе проводились впервые. Следует отметить, что вся миссия Deep Space 1 носит экспериментальный характер, и выяснение причин сбоя тоже является ее целью. Все остальные системы DS1 работают нормально. DS1 - это первая миссия про Программе Hового Тысячелетия (New Millennium Program), которая была предпринята NASA для разработки и полетных испытаний новых технологий, которые могут быть использованы в будущих космических экспедициях. Кроме ионного двигателя, на DS1 проводятся испытания новых солнечных батарей, автономных систем управления и различного научного оборудования. Hа DS1 должны быть проведены не только испытания, но и различные научные наблюдения. Этот корабль был запущен 24 октября 1998 г., в июле 1999 г. он должен долететь до астероида 1992 KD, а к 2001 г. , если будет решено продолжить миссию, может достигнуть двух комет. Hо чтобы все это произошло, должен заработать ионный двигатель, так как другого двигателя на DS1 нет. Hа снимке - Deep Space 1 Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: Метеорный поток Леонид приближается Привет всем! Вот, свалилось из Internet... Метеорный поток Леонид приближается [NASA] Готовы мы к этому или нет, но они приближаются - метеоры потока Леонид (Leonid). Утром 17 ноября частицы и осколки кометы Темпеля-Таттла (Tempel-Tuttle) врежутся в атмосферу земли со скоростью более 250 тыс. км/ч. Однако, это не представляет большой опасности для землян - только некоторые из этих частиц упадут на землю. Большинство из них сгорит в атмосфере, и мы увидим "падающие" звезды. По мнению специалистов нынешнее пришествие метеорного потока Леонид (а это бывает раз в 33 года) будет самым ярким явлением такого рода в этом столетии, так как его пиковая интенсивность превысит 40 падающих звезд в секунду. Большую часть своего времени комета Темпеля-Таттла проводит на окраине солнечной системы между орбитами Сатурна и Урана. Раз в 33 года она пролетает недалеко от Земли. Последний раз это случилось 10 месяцев назад в январе 1998 г. Комета прошла на расстоянии 53,82 млн км от Земли и ее легко можно было наблюдать в бинокль или в небольшой телескоп. Hо комета не приходит одна, ее сопровождает облако льда и пыли, которые вылетают из ядра кометы в результате ее нагрева солнечными лучами. Эти осколки продолжают двигаться вместе с кометой, образуя укий вытянутый поток метеоритных частиц. Метеорный поток Леонид вытянулся в длину на несколько миллионов километров, а поперечные его размеры составляют всего лишь 35 тыс. км. В прошлый раз поток Леонид бомбардировал Землю в 1966 г., тогда в некоторых местах можно было увидеть до 100 тыс. падающих звезд в час (на снимке слева). Hа этот раз лучше всего поток Леонид будет виден в Японии, Китае и других регионах восточной Азии. Hа снимке справа - поток Леонид в 1833 г. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: Астрономы исследуют новые спектральные диапазоны Привет всем! Вот, свалилось из Internet... Астрономы исследуют новые спектральные диапазоны [NASA] В Аризоне планируется установить новый телескоп, который будет наблюдать звезды в новом диапазоне длин волн - коротком субмиллиметровом. До сих пор астрономы исследовали излучение Вселенной в оптическом, ИК и радиодиапазонах. Телескоп Heinrich Hertz Submillimeter Telescope (HHT) будет иметь диаметр 10 м. Это совместный проект Обсерватории им. Стюарта Университета Аризоны в Туксоне и Института Радиоастрономии им. Макса Планка (Бонн, Германия). Этой осенью сотрудники обсерватории уже провели тончайшую настройку и юстировку всех 60 панелей, из которых состоит 10-метровое зеркало рефлектора телескопа. Для этого были использованы сигналы радиомаяка, установленного на околоземном спутнике. Hа этот процесс ушло 3 недели, в результате чего точность установки рефлектора составила 12 мкм (почти одна миллионная часть диаметра телескопа). Для нового телескопа был разработан субмиллиметровый приемник нового типа - болометр горячих электронов (Hot Electron Bolometer). С его помощью будет регистрироваться излучение с длинами волн в диапазоне от 300 до 1000 мкм. Основной целью создания этого телескопа является исследования холодных молекулярных облаков пыли и газа, находящихся на расстоянии более 100 световых лет от Солнца. По мнению теоретиков, такие облака образуются в результате взрыва сверхновой звезды, в результате которого и была образована в свое время наша солнечная система. Исследования таких облаков необходимы для лучшего понимания процесса образования звезд. До сих пор не ясно, почему вокруг некоторых звезд образуются планеты, а вокруг других - нет. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=

Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: ESA's Spanish astronaut looking forward to Space Station (Forwarded) Привет всем! Вот, свалилось из Internet... European Space Agency Press Release No. 48-98 Paris, France 12 November 1998 ESA'S SPANISH ASTRONAUT LOOKING FORWARD TO SPACE STATION ESA's first Spanish astronaut, Pedro Duque, "did a fantastic job in orbit and has a great future in the space programme", declared Curt Brown, the commander of the Space Shuttle Discovery which returned this past weekend from its STS-95 mission. Brown was speaking during a press conference on Sunday, the day after Discovery touched down at the Kennedy Space Center in Florida. Duque's STS-95 flight was the latest in a series of manned missions for Europe that have been amassing valuable experience for the International Space Station, the first element of which is to be launched next week. The international crew also included the oldest ever astronaut John Glenn (77) making his return to space 36 years after he became the first American to orbit the Earth. But Glenn was not the only crew member to go into the record books. Duque became the first Spanish national to go into space and, born in March 1963, more than a year after John Glenn's epic flight, he was also the youngest crew member. After returning to Earth on Saturday, Duque said he felt fine and would like to return to space in the future as an ESA astronaut on the International Space Station. "This mission, and ESA's direct involvement in the Space Station, shows that Europe is fully committed to exploiting space to the benefit of all people on Earth," said Duque. "I would certainly like to be a part of that." During the Space Shuttle flight of almost nine days, Duque's responsibilities included monitoring the performance of ESA's scientific experiment facilities, which carried experiments from scientists in Belgium, Britain, France, Germany, Italy, Spain Sweden and Switzerland. He also played a key role in the mission's medical experiments. The mission was a final test for some of the ESA science facilities, and experiments into the effects of weightlessness on various materials and substances, that may be flown in Europe's Columbus laboratory of the International Space Station. Investigators are already analysing telemetry data sent from the Shuttle, and samples from ESA's Biobox and the Advanced Protein Crystallisation Facility (APCF) are now being prepared for post-flight processing. The experiments in the other three ESA research facilities (MOMO, AGHF and FAST) will be recovered from the Shuttle, as scheduled, in late November or early December. Note to editors: The first element of the International Space Station is scheduled to be launched from Baikonur, Kazakhstan, on 20 November. ESA is one of five partners in the International Space Station programme, the largest international technical project ever undertaken. The other partners are the United States, Russia, Canada and Japan. ESA is currently in discussion with the partners to have ESA astronauts take part in missions to assemble the Space Station. Once the Space Station is operational, one or two European astronauts will board it each year for up to three months. Working as part of the six or seven-member crew, they will conduct scientific research, monitor experiments and contribute to general Space Station duties. Andrew Yee ayee@nova.astro.utoronto.ca Hа сегодня все, пока! =SANA=

Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: STARDUST Arrives At Kennedy Space Center For Launch Preparations Привет всем! Вот, свалилось из Internet... MEDIA RELATIONS OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011 http://www.jpl.nasa.gov Contact: Mary Beth Murrill FOR IMMEDIATE RELEASE November 12, 1998 STARDUST ARRIVES AT KENNEDY SPACE CENTER FOR LAUNCH PREPARATIONS NASA's Stardust spacecraft, designed to fly to a comet, collect a sample and return it to Earth, has arrived at the Kennedy Space Center, FL, to begin pre-launch processing. Launch aboard a Delta 7426 rocket is currently targeted for February 6, 1999 from Cape Canaveral Air Station. Stardust will be the first spacecraft ever to bring cometary material back to Earth for analysis by scientists worldwide. Comets are believed to contain the original building blocks of the planets and perhaps those of life itself. Early in Earth's history, comets laden with water ice slammed into the planet, maybe providing the source of our oceans. When Stardust returns its pristine comet samples, scientists will be able to examine for the first time the key ingredients of the original recipe that created the planets. The spacecraft was shipped from Lockheed Martin Astronautics, Denver, CO, aboard a C-17 aircraft and landed at Kennedy Space Center this morning. Stardust is being built Lockheed Martin Astronautics and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA. The principal investigator of the mission is space particle scientist Dr. Donald Brownlee of the University of Washington. Dr. Kenneth Atkins of JPL is the project manager. Stardust's main objective is to collect and bring 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 send back pictures of Wild-2, count the comet particles striking the spacecraft, and produce real-time analyses of the composition of the material coming off the comet. A unique substance called aerogel is the medium that will be used to catch and preserve comet samples. When Stardust swings by Earth in January 2006, the samples encased in a reentry capsule will be jettisoned and parachute to a pre-selected site in the Utah desert. The length of the Stardust main bus is 1.7 meters (5.5 feet), about the size of an average office desk. The spacecraft weighs 385 kilograms (849 pounds). Among the processing activities to be performed are installation and testing of the solar arrays, final installation and testing of some spacecraft instruments followed by an overall spacecraft functional test. The spacecraft can then be fueled and mated to the Star 37 solid propellant upper-stage booster. Meanwhile, at Launch Complex 17, the Delta II rocket will be undergoing erection and pre-launch checkout by Boeing. The first stage is scheduled to be installed into the launcher on January 5, 1999. Four solid-rocket boosters will be attached around the base of the first stage the next day. The second stage will be mated atop the first stage on January 8, and the spacecraft fairing will be hoisted into the clean room of the pad's mobile service tower January 11. Stardust will be transported to Complex 17 on January 28 for hoisting aboard the Delta rocket on Pad A and mating to the second stage. After the spacecraft undergoes state of health checks, the fairing can be placed around it three days later. Launch is currently targeted for February 6 at 4:08 p.m. EST. The 20-day launch opportunity ends February 25. Stardust is the fourth under NASA's Discovery Program of low-cost science missions, following Lunar Prospector, Mars Pathfinder and the Near Earth Asteroid Rendezvous (NEAR). The goal of NASA's Discovery Program is to launch many smaller missions with shorter development time that perform focused science at lower cost. JPL is a division of the California Institute of Technology, Pasadena, CA. ##### NOTE TO EDITORS: Images to accompany this release are available on the web at: http://www.ast.lmco.com/frameset.shtml?top=Media_Gallery,content=gallery_stard ust Hа сегодня все, пока! =SANA=

Дата: 16 ноября 1998 (1998-11-16) От: Alexander Bondugin Тема: Discovery of a Young Near-By Supernova Remnant (Forwarded) Привет всем! Вот, свалилось из Internet... Max Planck Institute for Extraterrestrial Physics Garching/Germany Contact: Bernd Aschenbach Phone: +49-89-3299-3561 Fax: +49-89-3299-3569 13-11-98 Discovery of a Young Near-By Supernova Remnant Young supernova remnant close to Earth discovered in hard X-rays towards the edge of the "Vela" supernova remnant confirmed by detection of g-ray lines from titanium-44 X-ray astronomers and g-ray astronomers of the Max Planck Institute for Extraterrestrial Physics in Garching/Germany, have discovered a young supernova remnant which is exceptionally close to Earth (Nature, Vol. 396, 12 November 1998). The remnant is just 700 light years away and it was created about 700 years ago when a star exploded in the southern sky in the constellation Vela ("sail"). "Our analysis shows that this is the nearest supernova remnant to have occurred during recent human history; other similarly close remnants in the Milky Way are of age of at least 10.000 years and more", Dr. Bernd Aschenbach from the Garching Max Planck Institute explains. "Now, it is up to optical astronomers and radio astronomers to confirm and extend our results." The discoveries are being reported in two separate contributions in "Nature's" issue of November 12, 1998, volume 396. The data on which these discoveries rest have been taken with the German X-ray astronomy satellite ROSAT, which has been developed and built under the direction of the Garching Max Planck Institute, and by the COMPTEL instrument, built by an international collaboration under the leadership of the Max Planck Institute as well, on board of the U.S. American g-ray astronomy Observatory "COMPTON". During the first all-sky survey with imaging X-ray telescopes also the Vela constellation has been mapped by ROSAT. This is a region in the sky well known to astronomers. In soft X-rays the Vela region is dominated by a huge and bright supernova remnant, the Vela supernova remnant, with a diameter of almost 200 light years, which still continues to expand at supersonic speed. More than 10.000 years ago a star exploded as a gigantic supernova and it gave rise to the clouds of hot gas which we see today. (Outside of the boundary of the explosion cloud Dr. Bernd Aschenbach has discovered numerous fragments of the progenitor star, a result which has been published in "Nature" in March 1995.) When Dr. Aschenbach was analysing the Vela supernova remnant in a way differing from standard software routines developed for ROSAT, in particular by extracting only the highest energy photons accessible with ROSAT, the image of the Vela supernova remnant changed drastically. For photon energies greater than 1300 electron volts the soft X-rays of the Vela supernova remnant had disappeared almost completely and a previously unknown, fairly circular emission region of about 2 degrees diameter, which is about four times the size of the full moon, emerged at the south-east corner of the Vela remnant (c.f. the pictures attached). "We were stunned; there is no way around, this is a new supernova remnant", Dr. Aschenbach says enthusiastically. "There are no other X-ray sources in the sky we know of which show this sort of shape and brightness distribution, except supernova remnants". The previously unknown object was named "RX J0852.0-4622" according to the position in the sky. Further analysis showed: "RX J0852.0-4622" is extremely hot at a temperature of about 30,000,000 Kelvin. This means: "RX J0852.0-4622" is a very young object, otherwise it would have cooled down to much lower temperatures already. But because "RX J0852.0-4622" is young it could have reached the angular extent of 2 degrees only if it is relatively close to Earth, otherwise just a small patch of X-ray emission would have been visible. "Detailed analysis and comparison with the well-studied remnant of the supernova which occurred in the year 1006 demonstrate that the new supernova remnant can not be significantly older than 1500 years and it can not be located at distances greater than 1000 parsec or 3300 light years", Dr. Aschenbach explains. "And the low X-ray surface brightness of "RX J0852.0-4622" can be attributed to a low matter density of just 0.04 gas and dust particles per cubic-centimeter, surrounding the star before it exploded. This is indeed low compared with standard values being about 20 times higher." The case that "RX J0852.0-4622" is a supernova remnant was finally settled by the g-ray astronomers. They specialize in studies of the g-ray emission from radioactive decay of atomic nuclei. During the sudden death of a star in a supernova, which takes a fraction of a second, matter density and temperature in the star reach levels at which atomic nuclei change and reformat. Most of the chemical elements including their isotopes are being released from the star to the world at supernova explosions, without these stellar ashes no life would have been possible. The matter expelled in the supernova process is further being used, it is the "raw material" for formation of the next generation of stars and planets. Many isotopes are not stable; they decay at a variety of times scales, which can be measured as "life-time" and which is a charateristic of each individual isotope. Eventually only the known "natural" chemical elements remain. Often the decay of an isotope is accompanied by the emission of g-rays of very specific energies. These g-ray lines are as unique as a finger-print for each radioactive isotope. Among other elements titanium-44 forms in a supernova explosion. It is produced exclusively during "silicon burning" and it decays over scandium to calcium by emitting a g-ray line of 1.156 million electron volt. The same group of g-ray astronomers had discovered this line for the first time from the well known young galactic supernova remnant "Cassiopeia A" already back some years ago.With the discovery of the titanium-44 g-ray line now from "RX J0852.0-4622" it was clear: "RX J0852.0-4622" is a young closeby supernova remnant. Despite the fact that the production yield of titanium-44 in "RX J0852.0-4622" is not known -- it is being produced in every type of supernova but at different rates -- the g-ray measurements could be used to further constrain the age and distance of "RX J0852.0-4622" making use of the "life-time" of titanium-44. It is concluded that the supernova occurred in the 13th century at a distance of about 700 light years from Earth. "This is the first time that a previously unknown supernova remnant has been found by means of the titanium-44 g-ray line", Dr. Anatoli Iyudin from the Max Planck Institute for Extraterrestrial Physics comments about this success. Coming years are very likely to show further discoveries of supernova remnants. In our Milky Way two to three stars in every 100 years are expected to explode; this follows from a comparison with external galaxies. But for the last 1000 years only seven remnants have been found so far. The remaining supernovae and their remnants might have escaped detection because the optical light might have gone lost in intervening interstellar gas and dust clouds. Hard X-rays and g-rays are not blocked by these clouds, so that the missing supernova remnants might be found soon by the instruments on board of the next X-ray astronomy and g-ray astronomy satellites, which are already being built and which are close to launch. IMAGE CAPTION: [http://www.mpg.de/news34_98.htm] Figure 1: At X-ray photon energies of more than 1300 electron volts a new X-ray source of circular shape emerges at the lower-left corner of the "Vela" supernova remnant; picture taken by the ROSAT X-ray astronomy satellite. X-ray astronomers and g-ray astronomers of the Max Planck Institute for Extraterrestrial Physics (MPE) have demonstrated that this new source is a young, previously unknown remnant, which has been borne in a supernova event at a distance of about 700 light years just 700 years ago. The white patch in the upper right shows the bright supernova remnant "Puppis-A", which is far behind the "Vela" supernova remnant and is unrelated to it. Photo by Max Planck Society/MPE. Figure 2: Two ROSAT X-ray images of the same region of the sky: The left hand image shows that the soft X-ray emission of the "Vela" supernova remnant taken for energies between 100 and 2400 electron volts dominates the region and outshines everything else except the very bright supernova remnant "Puppis-A" towards the upper right corner, which however lies behind and is not related to "Vela". Picking just the X-ray photons with energies greater than 1300 electron volts shows that "Vela" is soft, i.e. no "hard" X-ray photons are left; and the new supernova remnant with a diameter of two degrees, which the X-ray astronomers and g-ray astronomers of the Max Planck Institute have discovered, can clearly be seen in the lower left part. Photo by Max Planck Society/MPE. Figure 3: The image taken in the light of the 1.156 million electron volts g-ray line shows a clear concentration of titanium-44 in the area, which includes the X-ray object "RX J0852.0-4622" discovered by ROSAT. The g-ray line image has been produced from data taken with the COMPTEL instrument which was built by an international collaboration under the leadership of the Max Planck Institute for Extraterrestrial Physics. Because titanium-44 is exclusively produced in supernovae explosions there was no doubt for the X-ray astronomers and the g-ray astronomers the new object is a previously unknown supernova remnant. Photo by Max Planck Society/MPE. Andrew Yee ayee@nova.astro.utoronto.ca Hа сегодня все, пока! =SANA= </xmp