Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.astrolib.ru/rsn/1998/11/12/
Дата изменения: Unknown
Дата индексирования: Sat Apr 9 23:32:46 2016
Кодировка: Windows-1251

Поисковые слова: http www.stsci.edu science goods
Электронная библиотека астронома-любителя. RU.SPACE.NEWS - архив за 12 ноября 1998.
Электронная библиотека астронома-любителя. Книги по астрономии, телескопостроению, оптике.


Ru.Space.News:
Ноябрь 1998
ПнВтСрЧтПтСбВс
 
1
2345678
9101112131415
16171819202122
23242526272829
30
 

год:





  • Обзоры оружия и снаряжения
  • m31.spb.ru



  • AstroTop-100

    Яндекс цитирования


    0.025


    YouTUBE NauchFilm Channel

    Архив RU.SPACE.NEWS за 12 ноября 1998


    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: Европейское космическое агентство готовится к полету на Марс Привет всем! Вот, свалилось из Internet... Европейское космическое агентство готовится к полету на Марс [SpaceViews] Европейское космическое агентство (ESA) утвердило планы разработки проекта Mars Express, который включает и орбитальный и спускаемый на поверхность Марса аппараты. Экспедиция на Марс запланирована на 2003 г. Все 14 стран участниц Комитета научных программ ESA одобрили концепцию миссии, стоимость которой составит 150 млн евро (175 млн дол.). По заявлению директора ESA по науке Роджера Бонне (Roger Bonnet), это будет одна из самых дешевых и оригинальных экспедиций на Марс. Старт Mars Express запланирован на июнь 2003 г. Для запуска будет использована российская ракета "Союз". К Марсу корабль прилетит к Рождеству 2003 г. Hа космическом корабле будет установлено 7 блоков научной аппаратуры, некоторые из них будут дублировать те, что были потеряны при аварии российского корабля "Марс-96" в ноябре 1996 г. В состав аппаратуры войдут фотокамера высокого разрешения, несколько спектрографов и радар, способный обнаруживать объекты в толще земли. Этот радар будет использован для исследования воды, скрытого под марсианской поверхностью, которая находится там в виде рек, озер, ледников и вечной мерзлоты. Mars Express понесет и спускаемый аппарат Beagle 2 весом 60 кг, на котором будут установлены фотокамера и инструменты для исследования марсианского грунта и горных пород с целью определения прошлого этой планеты. Установка остального оборудования будет зависеть от финансовых возможностей разработчиков. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=
    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: NASA завершает испытания ракетного двигателя на атмосферном воздухе Привет всем! Вот, свалилось из Internet... NASA завершает испытания ракетного двигателя на атмосферном воздухе [NASA] Hациональное управление по аэронавтике и исследованию космического пространства США(NASA) успешно завершило двухлетние наземные испытания принципиально нового ракетного двигателя, который может существенно изменить будущее космонавтики - этот двигатель "дышит" кислородом воздуха. По заявлению разработчиков, они готовы продемонстрировать работу нового двигателя в полете. С таким двигателем весь космический корабль может быть использован неоднократно и после приземления он будет готов к полету уже через несколько дней, что существенно удешевит космические путешествия и откроет ворота в космос для многих стран мира. Часть полетного времени двигатель будет брать кислород непосредственно из атмосферного воздуха, что позволит сократить запасы газа на борту корабля. Соответственно и весить ракета с таким двигателем будет меньше. Для начального разгона двигателя будут использоваться специальные ракеты, мощность которых составит около 15% от мощности современных ракет-носителей. После того как космический корабль достигнет удвоенной скорости звука разгоняющие ракеты отделяются, и двигатель переходит на атмосферный кислород. После разгона до 10-кратной скорости звука включается обычная система вывода космического корабля на орбиту. По мнению NASA, при использовании таких двигателей запуск космического корабля удешевится настолько, что полет в космос станет доступен и для туристов. Цель NASA - снизить затраты на запуск одного фунта веса космического корабля с 10 тыс. дол. (около 22 тыс. дол. на килограмм) до нескольких сотен долларов. В создании воздушного ракетного двигателя принимали участие компании Aerojet, Rocketdyne, Astrox, Университеты Пеннсильвании и Алабамы. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=
    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: Выход в открытый космос на станции "Мир" прошел успешно Привет всем! Вот, свалилось из Internet... Выход в открытый космос на станции "Мир" прошел успешно 10 ноября в 22 часа 25 минут космонавты 26-ой экспедиции на станции "Мир" Геннадий Падалка и Сергей Авдеев совершили выход в открытый космос для установки на внешней поверхности орбитального комплекса научной аппаратуры и оборудования. Космонавты провели в открытом космосе 6 часов - практически полный рабочий день. Объем работ был довольно большим, так что пришлось шевелиться. В общей сложности космонавты установили на станции 17 блоков с оборудованием, самым крупным из которых была солнечная батарея нового типа. По словам разработчиков эта двухсекционная батарея является практически вечной, во всяком случае они гарантируют несколько десятков лет ее безотказной работы. Основной целью ее установки является изучение поведения новых материалов в открытом космосе. Была испытана и новая система защиты скафандров от внешнего космического излучения и выхлопных газов орбитальной станции. Установлен российско-французский датчик-ловушка космических частиц. Он пройдет проверку боем уже 17 ноября - именно тогда станция попадет в метеорный поток Леонид, а такое событие в окрестности Земли происходит раз в 33 года. Станция войдет в поток Леонид 17 ноября в 22 часа по московскому времени. В течение часа частицы будут бомбардировать станцию. По мнению ученых никакого ущерба станции нанесено не будет (частицы очень малы), но тем не менее экипаж во время прохождения метеорного потока будет на всякий случай находиться в спускаемом аппарате, чтобы в случае необходимости быстро вернуться на Землю. Часть оборудования была установлена в рамках программы разработки Международной космической станции. Кроме того космонавты в буквальном смысле слова вручную запустили на орбиту макет первого искусственного спутника Земли размером втрое меньше оригинала. Hачинка этого спутника была собрана российскими и францускими школьниками, он в течение нескольких минут передавал в космическое пространство несколько фраз на русском, французском и английском языках. К сожалению, космонавтам не удалось высвободить место на поверхности станции для российского прибора, предназначенного для измерения различных излучений. Источник: InfoArt News Agency Hа сегодня все, пока! =SANA=
    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: Leonid Meteor Shower Prospects for UK and Europe (Forwarded) Привет всем! Вот, свалилось из Internet... Royal Astronomical Society For immediate release: 10 November 1998 Ref. PN 98/23 Issued by: Dr Jacqueline Mitton RAS Public Relations Officer Office & home phone: Cambridge ((0)1223) 564914 Mobile phone: 0370 386133 FAX: Cambridge ((0)1223) 572892 E-mail: jmitton@dial.pipex.com and Peter Bond Space <b style="color:black;background-color:#ff66ff">Science</b> Advisor Phone: (0)1483-268672 Fax: (0)1483-274047 E-mail: 100604.1111@compuserve.com Leonid Meteor Shower Prospects for UK and Europe Professional and amateur skywatchers worldwide are awaiting the night of 17th/18th November with considerable anticipation because of the possibility that a spectacular meteor shower will take place. But what can we really expect to see in the UK and rest of Europe? According to the best data available, Europe is likely to experience a <b style="color:black;background-color:#66ff66">good</b> meteor shower, but not a truly exceptional one -- perhaps up to 100 meteors per hour if we are lucky. The best time to look will be between 1 a.m. and dawn in the early hours of 18th November. A storm of many thousands of meteors per hour could occur, but it is much more likely to be seen in the Far East -- China, Thailand, Japan -- than in Europe. Forecasting Metoer Showers Predictions of a meteor storm in 1998 are based on the fact that exceptional displays of the Leonid meteors -- so-called because they appear to radiate from a point in the sky within the constellation Leo -- tend to recur every 33 years or so. There is not always a great storm, however, such as the one in 1966 when observers in parts of the USA for a short time saw meteors at a rate of 40 per second. But forecasting meteor showers is not a precise business, unlike predicting eclipses, for example, for which the exact times and circumstances can be calculated in advance. The time when a meteor shower will peak, and the maximum rate at which meteors will appear to rain down, can never be anticipated with great certainty. They are something of a celestial lottery. For that reason, it is well worth looking out for meteors in the early hours of the 18th, if skies are clear, even from the UK. There is a slim chance of something exceptional, but a modest display at least is on the cards, and meteors are easy to observe. They are best seen with the naked eye and, during a shower, they can streak across almost any part of the sky, as long as the radiant point is above the horizon. If a Leonid storm takes place, it is unlikely to last more than an hour or so, but the gentler background shower carries on for a day or two. According to the experts the expected peak time of any storm is most likely to be about 7.45 p.m. (GMT). If this is correct, the storm would be finished several hours before the constellation Leo rises above the horizon in the UK. What Are Meteors? Meteors are caused by small fragments of material, mostly no larger than a grain of sand, which burn up as they enter Earth's atmosphere at high speed -- around 71 kilometres (45 miles) per second in the case of the Leonids. Leonid meteors are dust particles that have come off Comet Tempel-Tuttle. Most of this dust is still following the comet fairly closely in space. The comet takes 33 years to complete an orbit around the Sun, and planet Earth ploughs through its main dust cloud when the comet returns to our vicinity every 33 years. In the years when this happens, a strong shower or storm takes place. In the years in between, a very small number of Leonid meteors are seen in mid-November. Some meteor showers produce about the same rate of meteors around the same date every year. Regular annual showers happen when the dust from a comet has spread around the whole of the comet's orbit, something that takes place gradually over a long period of time. An example is the Orionids, a shower in late October each year caused by dust from Halley's Comet. Looking ahead to 1999, Comet Tempel-Tuttle will still be relatively nearby and some astronomers are predicting that the Leonid meteor display could be better next year than this. If that were to happen, then Europe is expected to be the ideal location. Do The Leonids Present Any Hazards? Most of the Leonids weigh about 1 millionth of a gram -- not much more than a particle of cigarette smoke. Normally, objects this size would pose no threat to spacecraft. However, when they are travelling many times faster than a bullet from a high velocity rifle, the threat increases significantly. Since the velocity of the meteor impacts is affected by a spacecraft's motion as it orbits the Earth, hits could occur at any speed between 65 and 80 km (40 and 50 miles) per second. These could result in some physical damage in sensitive areas as well as electrical short circuits, plasma discharges, and computer malfunctions, which may be sufficiently serious to disable a satellite. A form of sand-blasting can erode outer surfaces such as thermal blankets, mirrors and solar cells. Large impacting particles may even knock a satellite out of its normal position, as happened to the European Space Agency's Giotto spacecraft during its 1986 flyby of Halley's Comet. "These microparticles could penetrate a fairly weak spacecraft skin," said Professor Tony McDonnell of the Unit for Space <b style="color:black;background-color:#ff66ff">Sciences</b> and Astrophysics at the University of Kent in Canterbury. However, the most likely form of damage is to vulnerable power systems. "Perhaps a handful of satellites could have unusual electrical anomalies," said McDonnell. Past evidence suggests that the risks are fairly low. During the past four decades, only one spacecraft, the European Space Agency's Olympus satellite, is known to have been disabled by a (Perseid) meteor. Furthermore, no spacecraft were damaged by the 1966 Leonid storm. On the other hand, there are now more than 500 spacecraft orbiting the Earth, over 10 times as many as in the mid-1960s. "The biggest uncertainty is the hourly rate (of arrival)," said Professor McDonnell. "If this reaches 150,000 per hour, there will be all sorts of damage, but there may only be 1,800 per hour." While the probability of any satellite being hit is thought to be less than 0.1%, many spacecraft operators are taking no chances. The Space Shuttle mission that carried John Glenn was deliberately timed to avoid the Leonid shower. Cosmonauts on the Mir space station do not have the luxury of choosing their flight window. While the Mir station presents a large target for the Leonids, no serious damage is expected. However, the two crewmen may play safe by moving into the Soyuz lifeboat at the peak of the shower. Fortunately, the direction from which the particles approach the Earth is almost perpendicular to the direction of the Sun. This means that the chance of a direct hit will be substantially reduced since most satellites will already have their solar panels aligned edge-on to the shower. Further damage-limitation measures have been recommended by the European Space Operations Centre operated by the European Space Agency. These include turning spacecraft so that their most vulnerable systems are not in the direct line of fire; switching off high voltage systems; and putting a team of ground controllers on alert in case of emergencies. In the case of the Hubble Space Telescope, its all-important mirror will be turned away from the shower during observations of distant galaxies. Most of the scientific instruments on the European ERS-1 and ERS-2 Earth observation satellites and the Solar and Heliospheric Observatory (SOHO) will be powered down and placed in 'sleep' mode during the shower. SOHO and the American Advanced Composition Explorer (ACE), which are located 1.5 million km sunward of the Earth, will be particularly at risk since the main stream of meteors is expected to pass much closer to them than any of their Earth-orbiting brethren. Indeed, the trail of Leonids will actually travel between the Earth and these two solar observatories. More Information about the Leonid Meteors may be found at the following Web Sites: Leonid '98 Meteor Outburst Mission Homepage (P. Jenniskens - NASA) <b style="color:black;background-color:#ffff66">http</b>://<b style="color:black;background-color:#66ffff">www</b>-space.arc.nasa.gov/~leonid/1998.html Leonid Information for the Beginning and Advanced Meteor Enthusiast (G. Kronk) <b style="color:black;background-color:#ffff66">http</b>://medicine.wustl.<b style="color:black;background-color:#66ffff">edu</b>/~kronkg/leonids.html SKY Online's Meteor Page (Sky & Telescope magazine) <b style="color:black;background-color:#ffff66">http</b>://<b style="color:black;background-color:#66ffff">www</b>.skypub.com/sights/meteors/meteors.html Visual Material Sky & Telescope magazine (based in Boston, USA) has available for distribution: * still images from the 1966 Leonid storm, * artistic renderings * video of the 1997 Perseid and Geminid meteor showers * a broadcast-quality, 1-minute animation of why the Leonids occur by artist Don Davis. Anyone wanting these for reproduction or broadcast can contact Irene Szewczuk (irenes@skypub.com, phone 00 1 617-864-7360 x127) or Kelly Beatty (kbeatty@skypub.com, phone 00 1 617-864-7360 x148). Fax for both is 00 1 617-576-0336. Andrew Yee ayee@nova.astro.utoronto.ca Hа сегодня все, пока! =SANA=
    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: NEAR Weekly Report for Nov. 6, 1998 Привет всем! Вот, свалилось из Internet... NEAR WEEKLY REPORT November 6, 1998 MISSION OPERATIONS: The NEAR spacecraft state/configuration has remained nominal (Flight Computer #1 and Attitude Interface Unit #1 active). The Magnetometer and XGRS instruments remained on throughout this reporting period. The MSI and NIS were successfully powered up in preparation for the Eros Monochrome Light Curve on November 5 and NIS/MSI rotation Sequence Dry Run on November 9. Today's track should indicate how successful the Eros Monochrome Light Curve was. It should be noted this includes the first images of Eros taken by NEAR. Due to problems at DSN station 34, data recorded and played back from 98:303-00:55:03 to 98:303-20:31:43 was not recovered at the DSN station. Attempts to replay the data from the station produced data of a quality to low to be processed. This playback occurred during an unattended (MOC) playback. Data for the time period in question is non-recoverable. DSN 54 track on Wednesday November 4 was a "no go". The station reported problems at start of track and remained "red" the entire track. No data automatically dumped from the spacecraft via time tagged commands during this ATTENDED track was recovered by the DSN. Fortunately, an UNATTENDED track with station 25 followed the 54 track. The NEAR team manned the UNATTENDED track and successfully issued contingency commands to replay the data a second time. This time the data was retrieved from the DSN. No net data loss resulted. Upcoming Spacecraft Activities: November 9: NIS/MSI Rotation Sequence Dry Run November 18: Fancy Momentum Dump Test #2 November 19: Monochrome Light Curve of Eros November 19: NIS Cal Target Observation November 20: Eros Optical Navigation A (16 frames) Debra Fletcher 240-228-8274/Washington 443-778-8274/Baltimore Fax: 240-228-3237 Email: debra.fletcher@jhuapl.<b style="color:black;background-color:#66ffff">edu</b> Bldg.-Rm.: 2-155 The Johns Hopkins University Applied Physics Laboratory 11100 Johns Hopkins Road Laurel, MD 20723-6099 Hа сегодня все, пока! =SANA=
    Дата: 12 ноября 1998 (1998-11-12) От: Alexander Bondugin Тема: Goddard spacecraft prepared for encounter with Leonid meteor storm (Fo Привет всем! Вот, свалилось из Internet... Mark Hess/Jim Sahli Goddard Space Flight Center Nov. 9, 1998 Greenbelt, MD 20771 (Phone: 301-286-8955) RELEASE NO: 98-184 GODDARD SPACECRAFT PREPARED FOR ENCOUNTER WITH LEONID METEOR STORM Flight controllers are laying plans to prepare an orbiting fleet of 22 Goddard spacecraft for the upcoming Leonid meteor storm, predicted to be the fiercest in more than three decades. The annual Leonid shower -- this year a storm -- is expected to be unusually intense because the Earth is crossing Comet Tempel-Tuttle's orbital path at a time when the comet has recently passed by. This happens once every 33 years when Tempel-Tuttle makes its closest approach to the Sun. The Sun's radiation boils bits of dust and sand off the comet, littering its path with debris. Where possible, controllers will change the orientation of satellites to reduce the possibility that one of these tiny particles (1 to 100 microns in size, or about the size of a small sand grain) will strike and disable a spacecraft. However, Leonid storms pose a greater than usual threat to spacecraft not only because of the many tiny meteors (thousands per hour) hitting our atmosphere, but also the tremendous velocities of the particles. As the Earth moves across the comet's trail, Leonid particles will enter the planet's atmosphere. Like two freight trains hurtling at one another on the same track, the distance between the massive debris cloud and the Earth closes at a mind-boggling 45 miles per second, or over 200 times the speed of sound. In contrast, Perseid meteors reach speeds of about 37 miles per second, and typical daily meteors achieve velocities of about 12 miles per second. On spacecraft where it is practicable, high voltage systems that supply instruments will be turned off, or ramped down, to safeguard against the potential for electrical damage as a result of the satellite's plunge into the debris cloud. The tiny meteors can hit the spacecraft like a sandblaster and disintegrate, creating a cloud of electrically charged plasma. Under the right conditions, this plasma cloud can set off a chain reaction causing a massive short circuit. The loss of the European Space Agency's Olympus communications satellite in 1993 was attributed to a strike from the Perseid shower, and the resulting plasma discharge that zapped the spacecraft's delicate electronics. The 22 NASA spacecraft under Goddard's control -- from the 24,500 pound Hubble Space Telescope to the 25-year old, 800 pound IMP-8 satellite -- will be continuously monitored during the peak of the storm, and some maneuvered to provide the greatest protection possible from debris. "Each individual mission and project team reviewed its procedure for dealing with this annual phenomena, and has a specific implementation plan for the Leonid meteor storm," said Philip E. Liebrecht, Associate Director for Networks and Mission Services. "Each spacecraft has an operating plan that balances the risk of taking specific defensive measures against the risk of taking no action. We've had independent review teams assess our plans, and I think we are doing everything prudent and practicable to ensure the safety of our spacecraft." The Leonid meteor shower arrives every November. It takes its name from the constellation Leo, the area of the sky where the meteors appear to originate. The shower's small particles are completely vaporized high in the Earth's atmosphere, and present no danger to the Earth's surface or to aircraft. Historically, the most active Leonid showers occur during the first two years following the comet's closest approach to the Sun. This last occurred on Feb. 28, 1998. This year's outburst is projected to be less severe than that observed in the last 33-year cycle, which occurred in 1966. The peak time for the Leonid meteor storm will be Nov. 17, sometime between 11:43 a.m and 5:43 p.m. Eastern Standard Time. For the past several weeks, engineers at Goddard have been reviewing the status of all the spacecraft under their control and developing ways to reduce exposure to the meteor storm. In general, the health of these spacecraft will be monitored before, during and after the storm, and commands to a number of the spacecraft will be stopped or curtailed during this period. The Hubble Space Telescope will be maneuvered so that its mirrors face away from the storm. Its solar arrays will be rotated so only the edges are exposed to oncoming particles. Controllers won't turn Hubble off during the storm, but rather use the 10-hour period that Hubble is maintained in this attitude to take a long-exposure picture (for more on this, check out <b style="color:black;background-color:#ffff66">http</b>://<b style="color:black;background-color:#66ffff">www.stsci.edu</b>/ftp/proposer/leonid.html). Some spacecraft, like the Tropical Rainfall Measuring Mission, are already in the ideal orientation for the storm, and only an adjustment to position the solar arrays "edge on" to the storm will be needed. The Rossi X-ray Timing Explorer's instruments will be turned off to protect the spacecraft's high voltage devices from a potential massive short circuit similar to what happened to Olympus. For the Advanced Composition Explorer, the solar arrays will be rotated, and high voltage supplies for instruments will be ramped down. Since the center of the Leonid stream is closer to the L-1 orbit (1 million miles from the Earth toward the Sun) than to Earth, ACE will see an even more intense storm than Earth-orbiting satellites. Risk reduction procedures will be followed for other spacecraft including the Extreme Ultraviolet Explorer, Compton Gamma Ray Observatory, Upper Atmosphere Research Satellite, Total Ozone Mapping Spectrometer, Fast Auroral Snapshot, Solar Anomalous Magn