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Дата: 22 июня 1998 (1998-06-22) От: Alexander Bondugin Тема: SpaceViews - June 1998 [1/16] Привет всем! Вот, свалилось из Internet... This is the June 1998 "SpaceViews" (tm) newsletter, published by the Boston chapter of the National Space Society. For a description of related e-mail lists maintained by the Boston NSS, or to stop receiving this SpaceViews newsletter, see the instructions at the end of this message. The next Boston meeting is June 4, 1998, 7:30pm 8th floor, 545 Main Street (Tech Square), Cambridge; see "Upcoming Boston NSS Events" Rainier Anacker on "Designing a Small Rocket for L.E.O." Future meetings are on the first Thursdays of each month: July 2, August TBD, September 3 SpaceViews is available on the WWW at http://www.spaceviews.com (NEW!) and by FTP from ftp.seds.org in directory /pub/info/newsletters/spaceviews See the very end for information on membership, reprinting, copyright, etc. Copyright (C) 1997 by Boston Chapter of National Space Society, a non-profit educational 501(c)3 organization. All articles in SpaceViews represent the opinions of the authors and do not necessarily represent the views of the Editor, the National Space Society (NSS), or the Boston chapter of the NSS. S P A C E V I E W S Volume Year 1998, Issue 6 June 1998 http://www.spaceviews.com/1998/06/ *** News *** New Space Station Plan Approved Hubble Sees Possible Extrasolar Planet Shuttle Launch on Schedule Despite Mir Problems Satellite Failure Disrupts Pager Service Instrument Errors May Explain Away Small Comets MGS Finds New Evidence of Watery Past on Mars HGS-1 to Make Second Lunar Flyby X Prize Announces Sweepstakes More Near-Earth Asteroid Searches Needed SpaceViews Event Horizon Other News *** Articles *** The Soviets Reach for the Moon [part 2] Doing Space: Why Do We Go? Space Burial: An Analysis *** Book Reviews *** Quick Looks at Four Books *** NSS News *** Upcoming Boston NSS Events The 1998 International Space Development Conference Mars Society Founding Convention Announcement *** Regular Features *** Jonathan's Space Report No. 361 Space Calendar Editor's Note: Check out our updated section of the SpaceViews Web site on the Russian space station Mir. We've added new links, updated information, and a poll on the future of the station. We'll be adding an article search engine there soon as well. It's at http://www.spaceviews.com/features/mir Also, we've finishing up going through the several hundred repsonses to our reader survey we mailed with the April issue. Look for some changes in SpaceViews, based on the results of that survey, in the coming month or so. -- Jeff Foust, Editor jeff@spaceviews.com *** News *** New Space Station Plan Approved Representatives from the 16 countries participating in the International Space Station (ISS) program approved Sunday, May 31, a revised assembly schedule that officially delays the first launch of a station component until this November and shuts down Mir next July. The meeting, held at Cape Canaveral, Florida, also revised downward the Russian contribution to the station by deleting two life-support modules and a storage chamber from the station design. Under the new plan, the first module, the Russian-built control module, will be launched on a Proton from Baikonur, Kazakhstan, November 20. The module was also renamed Zarya -- Russian for "sunrise" -- at the meeting. The first ISS shuttle flight was scheduled for December 3, when the shuttle Endeavour will launch the Unity docking node into orbit. Astronauts will perform several spacewalks to attach Unity to Zarya. Earlier in May NASA officials admitted that the first station launches, first planned for late 1997, then pushed back to this summer and then this August and September, would not take place before late 1998. The long-delayed service module, which has delayed the beginning of station assembly by a year, is now planned for an April 1999 launch. That launch will be followed up by a Soyuz launch of the first ISS crew, commanded by American astronaut William Shepherd, in July. At that time Russia plans to abandon its current space station, Mir. Russian officials had hoped to keep the station operating until the end of the year but admitted they don't have the money to support both ISS and Mir operations at the same time. Last week, Russian Space Agency head Yuri Koptev hinted he would shut down Mir up to a year early to make up for a shortfall in funding for the agency. He later backed off those plans after a meeting with top Russian officials, who urged the agency to seek outside, commercial funding to continue to support ISS and Mir. Russia plans to deorbit Mir after the station is abandoned in July 1999. Hа сегодня все, пока! =SANA=

Дата: 22 июня 1998 (1998-06-22) От: Alexander Bondugin Тема: SpaceViews - June 1998 [2/16] Привет всем! Вот, свалилось из Internet... Hubble Sees Possible Extrasolar Planet Astronomers using the Hubble Space Telescope have found what may be an extrasolar planet -- the first seen directly -- that has been ejected from its parent stars. The object, named TMR-1C, was seen in an infrared image of a star-forming region in the constellation Taurus some 450 light-years from the Earth. The image shows the object with a tendril of light stretching back to a binary star system 210 billion km (130 million mi.) away. "If the results are confirmed, this discovery could be telling us gas giant planets are easy to build," said astronomer Susan Terebey of the Extrasolar Research Corporation (ERC) of Pasadena, California. "It seems unlikely for us to happen to catch one flung out by the stars unless gas giant planers are common in young binary systems." Terebey and a team of astronomers from ERC and the Jet Propulsion Lab made the discovery in an image taken by Hubble's NICMOS infrared camera and spectrograph. "This is incredibly exciting, seeing a possible extrasolar planet for the first time," said Alan Boss, an astrophysicist at the Carnegie Institution of Washington. "This is a major, unprecedented observation. It is as important as the first indirect observation of an extrasolar planet." The size of the planet is dependent on its age. If the body is very young -- a few hundred thousand years old -- it should be no larger than a few times the mass of Jupiter. However, if it is much older -- up to ten million years old -- the body would be much heavier, and more likely a brown dwarf or giant protoplanet. If it is young, then then planet challenges current theories of planetary system formation which require millions of years for planets to form. "This observation pushes back the clock on planet formation and offers short time scales which allow us to see how things form," Terebey said. "If this is a planet and the system is about 300,000 years old, then the slower, conventional theory doesn't fit," Boss said. The object might have been dismissed as a background star had it not been for the strange filament of light stretching from the star to the object. Terebey thinks it might be a "tunnel" cut by the object through the surrounding dust cloud, creating a path for light to escape. Astronomers still believe there is a 2 percent chance that the object is a background star coincidentially located at the end of the tendril. The object was likely ejected from the binary star system in a gravitational slingshot maneuver. "We know that many triple star systems eventually toss out the lowest mass object," Terebey said. TMR-1C is moving away from its parent stars at an estimated 10 km/sec (6 mi/sec). Future observations are planned to confirm the motion of the object and to take its spectrum, in an effort to find if it is a planet, brown dwarf, or protoplanet. "These future observations will be critical in verifying that the object is truly a planet and not a brown dwarf," said Ed Weiler, director of NASA's Origins program charged with looking for extrasolar planets. "If the planet interpretation stands up to the careful scrutiny of future observations," Weiler said, "it could turn out to be the most important discovery by Hubble in its 8-year history." Shuttle Launch on Schedule Despite Mir Problems The countdown began late Saturday, May 30 for the June 2 launch of the shuttle Discovery on the ninth and final docking mission with the Russian space station Mir despite problems with a computer on the station. Mission STS-91 is scheduled for launch on Tuesday, June 2, at 6:10 pm EDT (2210 UT). No problems have been reported with the shuttle since the countdown began. However, a key computer system on Mir failed May 30, taking out the station's attitude control system. Without the system functioning Mir's solar panels cannot maintain the proper alignment with the Sun, and thus generate less power for the station. The two Russian cosmonauts and one American astronaut on Mir turned off non-essential systems while making repairs to the computer system. They believe that the system can be up and running as early as Sunday night. NASA officials said that while the attitude control system needs to be operating for the shuttle to successfully dock with Mir, they believe it will be working by Tuesday afternoon's launch. Weather, however, may yet delay the launch. Meteorologists over the weekend predicted a 40 percent chance that clouds and scattered showers could delay a launch attempt Tuesday. The shuttle crew includes five astronauts, commanded by veteran astronaut Charlie Precourt, and Russian cosmonaut Valery Ryumin. On the trip back the crew will include American astronaut Andy Thomas, who will be returning from a four-month stay on Mir. Also on board the shuttle is the Alpha Magnetic Spectrometer (AMS). This instrument, developed by an international consortium led by Nobel laureate Dr. Samuel Ting of MIT, is designed to search for evidence of antimatter in the universe. The instrument will later by carried on the International Space Station (ISS). The mission will also feature the first use of the new lightweight external fuel tank. The tank, needed to increase the payload of the shuttle for future space station missions, was successfully tested on the pad May 18. The STS-91 mission is the last shuttle mission for several months. Earlier in May NASA officials admitted that STS-88, the first ISS shuttle mission, will launch no earlier than November. The launch was scheduled first for December 1997, and then this July. With the delay of STS-93, the flight of Columbia to launch the AXAF X-ray satellite, from August until December, the next scheduled shuttle launch is not until October 29, when Columbia launches on STS-95, a mission featuring Senator and former astronaut John Glenn. Hа сегодня все, пока! =SANA=

Дата: 22 июня 1998 (1998-06-22) От: Alexander Bondugin Тема: SpaceViews - June 1998 [3/16] Привет всем! Вот, свалилось из Internet... Satellite Failure Disrupts Pager Service The failure of a communications satellite late Tuesday, May 19, disrupted pager service to up to 90 percent of American pager users as well as caused problems for some television transmissions as the owner of the satellite began moving another satellite in position. The Galaxy 4 satellite, operated by PanAmSat, suffered a failure in its control system around 6pm EDT (2200 UT). Company officials, reporting the problem about six hours later, blamed a problem with an on-board processor that keeps the satellite pointed towards the Earth. The processor failure caused the satellite to rotate and lose contact with the Earth, although ground controllers were still able to receive telemetry from the satellite and upload commands. Robert Bednarek, senior vice president of PanAmSat, said in a press release company engineers were working on a solution to the problem, but the company later reported that the satellite would likely not come back online. "We don't want to hold out false hope to our customers," Bednarek told CNN. "We will continue to monitor it, but at this point we are not advising anyone to rely on the restoration of this satellite." The company initated a backup plan, moving another of its satellites, Galaxy 6, from 74 degrees West longitude to 99 degrees West, the current poition of Galaxy 4. Galaxy 6 reached its new position in about 6 days, Bednarek said. PanAmSat has also made available services on the nearby Galaxy 3-R satellite, and is working with other companies to restore services for its customers. "Satellite capacity has been identified and made available to customers," Bednarek said, "and PanAmSat is making every effort to assist those customers in migration to that spare capacity." Galaxy 4, an HS-601 satellite built by Hughes Space and Communications Company and launched in June 1993, handles an estimated 80 to 90 percent of the telephone pager traffic for the U.S. and Canada. Scott Baradell, a spokesman for PageNet, a company hard-hit by the satellite failure, told CNN that there are 40 to 45 million pagers in use in the United States. The failure is the first wide-spread outage ever recorded for pager services, according to experts. The satellite also handled some television traffic for the three major American networks and some other services. CBS, the largest user of the satellite, moved to its backup, Galaxy 7, and reported no serious disruptions. The networks mainly used the satellite for transmitting prerecorded programming to affiliates a few days in advance of broadcast. Some other networks, such as CNN's Airport Channel, which provides CNN programming in selected airport terminals, were also hit by the satellite outage. National Public Radio reported it could not deliver its programming to affiliates, and Reuters news stories sent via satellite were also not arriving. Instrument Errors May Explain Away Small Comets In a series of presentations punctuated with often heated debate Tuesday, May 26, several scientists presented evidence that dark spots seen in images of the Earth by one satellite may be caused by instrument errors, not "small comets" striking the atmosphere. However, Louis Frank, the leading proponent of the small comet theory, defended his position before a packed audience during the American Geophysical Union's spring meeting in Boston, a year after first presenting the new data. Several presentations at the meeting focused on the idea that problems with the instrument, perhaps exacerbated by data analysis techniques, may cause the black spots seen in images by a camera on the Polar spacecraft. George Parks of the University of Washington compared images taken with Polar's VIS camera, which showed the black spots, with images taken with an ultraviolet camera on the same satellite. He found that both generated the same number of dark spots, even though the smaller pixel size of the ultraviolet camera should mean it should see four times as many if the dark spots were real. The dark spots "are caused by the instruments themselves," he concluded. Another hypothesis was forwarded by Larry Paxton of the Applied Physics Lab of The Johns Hopkins University. He found evidence that a large amount of long wavelength light was leaking into the VIS camera, allowing it to see deeper into the Earth's atmosphere and observe clouds, which should not be visible in the short-wavelength light the VIS camera is designed to see. Paxton believes the dark spots could then be gaps in the cloud cover inadvertently observed by the VIS camera. This would also explain why more dark spots are seen in the morning than the afternoon, as cloud cover is usually lower in the morning. Efforts to detect the small comets themselves were also presented. Searches for the comets using the Spacewatch telescope in Arizona and a Navy radar system designed to detect satellites both failed to find any objects resembling the hypothesized small comets. Frank, however, remained convinced that the dark spots seen in the Polar data represent small comets. He claimed that he could detect variation in the number of dark spots as a function of both altitude of the satellite and time of the year, correlating the latter with meteor impact rates measured separately. The debate between Frank and other scientists was often heated. "Why people don't do this work is beyond me," he said at one point in his presentation. Another time he claimed his work was being misrepresented by another presenter, calling that "simply detestable." The session was the latest salvo in a debate dating back over more than a decade on whether the dark spots see in data from two spacecraft represent objects striking the Earth, or are just instrumental noise. Frank, who originally proposed the small comets theory in 1986 based on dark spots seen in images from the Dynamics Explorer 1 satellite, revived the theory last year when he presented the data from Polar at the AGU's spring meeting. The announcement was, at the time, hailed as a vindication for Frank's theory, which had not gained wide acceptance from the scientific community after the 1986 announcement. The announcement was even heralded with a NASA press release. In that release Frank's findings were supported by Thomas Donahue, an atmospheric physicist at the University of Michigan. "The Polar results definitely demonstrate that there are objects entering the Earth's upper atmosphere that contain a lot of water," he said last year. Donahue is more skeptical of the validity of the data now, calling Frank's claims "seriously challenged." "There's a strong likelihood that it is instrumental," he said. Hа сегодня все, пока! =SANA=

Дата: 22 июня 1998 (1998-06-22) От: Alexander Bondugin Тема: SpaceViews - June 1998 [4/16] Привет всем! Вот, свалилось из Internet... MGS Finds New Evidence of Watery Past on Mars New data returned by the Mars Global Surveyor (MGS) spacecraft have provided additional evidence that the planet was once much warmer and wetter, scientists announced Wednesday, May 27. Other new MGS findings reported at the American Geophysical Union's spring meeting in Boston include the discovery of deep chasms in Mars's north pole, a crater that once held a pond of water, and a pair of bulges in the planet's upper atmosphere. The new evidence for liquid water on ancient Mars comes from the discovery of a large deposit of hematite crystals, detected using MGS's Thermal Emission Spectrometer (TES). The TES detected the region, about 500 km (300 mi.) in diameter, along the Martian equator. Hematite was already known to exist on Mars; fine grains of the iron-rich mineral help give the Red Planet its distinctive color. The deposit found by MGS, though, is a coarse-grained sample that on Earth is formed by hydrothermal systems, as the large crystals grow in warm waters. "The existence and location of these deposits will provide a positive indication that hot water once existed near the Martian surface," said Arizona State University's Phil Christensen, principal investigator of the TES instrument. "Even more intriguing is the possibility that the hematite may have initially precipitated from a large body of water." The heat and liquid water required to form the crystals are also two of the primary ingredients needed for life to form, making the site of the deposit one of the likeliest locations to find evidence of past Martian life. "This is one of the best places to look for evidence of life on Mars," Christensen said. Data from MGS's laser altimeter have given planetary scientists a new view of the planet's northern polar cap. The data show the cap reaches a peak altitude of 2 to 2.5 km (1.25 to 1.5 mi.) above the surrounding terrain. However, embedded within the cap are large, deep chasms that cut up to 1.6 km (1 mi.) deep. Although the laser altimeter was designed to measure the elevation of the surface of Mars, it has also detected clouds above the polar cap. Principal investigator David Smith of NASA's Goddard Space Flight Center said additional work is needed to determine the type of clouds observed. Images of the southern regions of Mars turned up an interesting crater. Mars Orbiter Camera principal investigator Michael Malin showed an image of the unnamed crater, whose walls show evidence of fluid seepage. A dark area in the bottom of the crater is also visible. Malin suggested that the easiest interpretation is that water seeped out of the side of the crater relatively recently in the planet's history and accumulated at the bottom. The dark area may be sediment left behind in the crater's pond. Data from the accelerometer on the spacecraft, used to monitor the aerobraking of the spacecraft, has uncovered two large bulges in the Martian atmosphere. The bulges rotate with the planet on opposite sides and cause variations in pressure of the upper atmosphere by up to a factor of two. The findings announced Wednesday mainly came from data collected late last year and earlier this year, after the spacecraft stopped aerobraking in March. The spacecraft will remain in this aerobraking hiatus, collecting data, until September, when it begins the final phase of aerobraking to bring it into a circular mapping orbit by March 1999. MGS instruments, which were turned off in early May while Mars passed behind the Sun as seen from Earth, are being turned on again, project officials reported. HGS-1 to Make Second Lunar Flyby Hughes Global Services (HGS), who sent the HGS-1 satellite around the Moon earlier this month as the first commercial spacecraft to fly to the Moon, will send the spacecraft around the Moon again in an effort to better improve its orbit, company officials reported Monday, May 18. The spacecraft, which rounded the Moon on May 13, arrived back in the vicinity of Earth May 16. Instead of firing the satellite's thrusters to put the spacecraft into orbit around the Earth, a shorter burn was used to put the spacecraft on a looping 15-day orbit. A second burn, scheduled for June 1, will put the spacecraft on course for its second lunar flyby on June 6. Two final burns on June 12 and 13 will put HGS-1 into geosynchronous orbit. HGS President Ronald Swanson said the change in plans was an effort to improve the orbit of the spacecraft. "A second lunar flyby will make the orbit even better and will increase the satellite's attractiveness to potential customers," he said. Swanson said Hughes orbital analysts "said one more loop around the moon would improve the orbit, with little impact on the satellite's operational life -- so we're going for it." No additional lunar flybys are planned, Swanson said, because additional flybys would provide diminishing returns on the quality of the orbit. The satellite, originally named AsiaSat 3, was launched on Christmas Day 1997 by a Russian Proton rocket from Baikonur, Kazakhstan. The upper stage of the Proton failed to fire, stranding the satellite in a useless elliptical, inclined, transfer orbit. After insurers took ownership of the satellite from Hong Kong-based AsiaSat, they gave the title over to Hughes, who started a series of thruster burns in April to raise the satellite's orbit in preparation for a lunar flyby. Hughes and the insurers will share any profits from the use of the satellite, should it arrive in a usable orbit. The idea of using the Moon to salvage HGS-1 came from outside Hughes. Rex Ridenoure of Microcosm told SpaceViews that Ed Belbruno, of Innovative Orbital Design, suggested a trajectory that used the Moon to salvage the satellite, and following some analysis and validation at Microcosm, Ridenoure passed that information on to Hughes in mid-January. Hа сегодня все, пока! =SANA=

Дата: 22 июня 1998 (1998-06-22) От: Alexander Bondugin Тема: SpaceViews - June 1998 [5/16] Привет всем! Вот, свалилось из Internet... X Prize Announces Sweepstakes The X Prize Foundation, an organization sponsoring a $10-million prize to promote space tourism, announced a contest of a different kind May 20: a swee