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By Daniel Fischer Every page present in Europe & the U.S.!
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The latest issue!
| A German companion! (SuW version) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
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First permanent crew chases ISS after foggy launchFrom now on always some humans in space, forever?Perhaps October 31, 2000, will one day be noted in history books as the day when mankind moved into space forever: With the launch of "Expedition One" to the International Space Station at 7:53 UTC (which was obscured by a lot of fog, conditions under which a space shuttle could never have flown) a permanent presence of at least 3 astro/cosmonauts in Low Earth Orbit should have been established for the next 15 years or so - and by then spaceflight and space stations should have become a common thing, well, maybe...The orbital insertion of Soyuz was 233 x 182 km, and several thruster firings are currently correcting that to 392 x 374 km, the current orbit of the ISS. Docking is planned for 9:24 UTC on Nov. 2nd, and Shepherd, Gidzenko and Krikalev will spend the next three months readying the station for the first big laboratory module Destiny and preparing it for the early scientific work. But don't expect to follow the early ISS mission on TV: Coverage will be sporadic. |
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Decision on Mir's demise delayed til next February, but hopes fadeThe Russian government has provided enough funds for Progress ships to keep Mir in orbit until its 15th launch anniversary - but unless MirCorp or other investors come up with real cash and not just promises really quickly, the station will be deorbited soon thereafter. While there seems to be a wide consensus among Russia's space planners that one should rather concentrate on the ISS and get rid of Mir ASAP, there is also the feeling that with Mir the last main purely Russian space institution would be lost - and few politicians want to be the ones who actually make the final decision ...
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| NASA reveals Mars plans for the next two decadesIt's still ambitious but much less hectic than previous plans - and the first sample return mission moves at least 6 years further down the road: That is the quintessence of NASA's new Mars exploration program for the next 20 years, as revealed after six months of internal discussion, on Oct. 26. The new program incorporates the lessons learned from previous mission successes and failures, and builds on scientific discoveries from past missions. The NASA-led effort to define the program well into the next decade focused on the science goals, management strategies, technology development and resource availability in an effort to design and implement missions which would be successful and provide a balanced program of discoveries. International participation, especially from Italy and France, will add significantly to the plan.A basic feature of the plan is that each window from 2001 on will be used only for one major mission, alternating an orbiter and a lander. In addition to the previously announced 2001 Mars Odyssey orbiter mission and the twin Mars Exploration Rovers in 2003, NASA plans to launch a powerful scientific orbiter in 2005. This mission, the Mars Reconnaissance Orbiter, will focus on analyzing the surface at new scales in an effort to follow the tantalizing hints of water from the Mars Global Surveyor images and to bridge the gap between surface observations and measurements from orbit. For example, the Reconnaissance Orbiter will measure thousands of Martian landscapes at 20 to 30 cm resolution, good enough to observe rocks the size of beach balls. NASA then proposes to develop and to launch a long-range, long-duration mobile science laboratory that will be a major leap in surface measurements and pave the way for a future sample return mission. NASA is studying options to launch this mobile science labroatory mission as early as 2007. This capability will also demonstrate the technology for accurate landing and hazard avoidance in order to reach what may be very promising but difficult-to-reach scientific sites. NASA also proposes to create a new line of small "Scout" missions which would be selected from proposals from the science community, and might involve airborne vehicles or small landers, as an investigation platform. Exciting new vistas could be opened up by this approach either through the airborne scale of observation or by increasing the number of sites visited. The first Scout mission launch is planned for 2007 as well. In the second decade, NASA plans additional science orbiters, rovers and landers, and the first mission to return the most promising Martian samples to Earth. Current plans call for the first sample return mission to be launched in 2014 and a second in 2016. Options which would significantly increase the rate of mission launch and/or accelerate the schedule of exploration are under study, including launching the first sample return mission as early as 2011. Technology development for advanced capabilities such as miniaturized surface science instruments and deep drilling to several hundred feet will also be carried out in this period. The agency's Mars Exploration Program envisions significant international participation, particularly by France and Italy. In cooperation with NASA, the French and Italian Space Agencies plan to conduct collaborative scientific orbital and surface investigations and to make other major contributions to sample collection/return systems, telecommunications assets and launch services. Other nations also have expressed interest in participating in the program. "NASA's new Mars Exploration Program may well prove to be a watershed in the history of Mars exploration," predicts Dr. Ed Weiler, NASA's Associate Administrator for Space Science: "With this new strategy, we're going to dig deep into the details of Mars' mineralogy, geology and climate history in a way we've never been able to do before."
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| Four more moons of Saturn bring total to 22An international team of eight "satellite hunters," astronomers who pluck tiny specks of light out of the distant solar system, has discovered four new outer moons of Saturn orbiting at least 15 million kilometers from the surface of the giant planet. The discovery gives Saturn a total of 22 known moons, surpassing the 21 orbiting Uranus. Nothing is known about the four new moons except for their brightness. Estimates of their size, between 10 and 50 kilometers across, are based on assumptions of their reflectivity. Observed from Earth-bound observatories, the moons appear as faint dots of light moving around the planet.The discovery of the four new moons was made using a technique developed by Brett Gladman while he was a student at Cornell (he now works in France). The technique, which also was used in the discovery of five new Uranian moons, uses CCDs to detect the distant points of light. Several of these digital images, taken once every hour, are then compared, using computer software to pick out a moving point of light against the known star background of the sky. Between 1997 and 1999, the same team discovered a total of five new moons of Uranus. All five, like the newly discovered four outer moons of Saturn, are irregular satellites. An irregular satellite's orbit is "long and looping," unlike the orbit of an inner moon, which is nearly circular and lies in the planet's equatorial plane. The great distance that the moons orbit from Saturn indicates that they were captured into orbit after the planet formed, unlike the larger regular satellites that are thought to have coalesced from a disk of dust and gas that surrounded the planet as it formed.
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| NEAR came to within 5 km of Eros!Early on Oct. 26 NASA's NEAR Shoemaker spacecraft swooped just 5.4 km over parts of the asteroid Eros which it has been orbiting since February. Then a three-minute engine burn lifted the spacecraft from the low-altitude orbit toward a more stable position 200 km from the center of the asteroid. The elevation of the flyby was similar to the cruising altitude of a commuter jet on Earth: No space probe has ever been so close to a minor planet. The spacecraft was never in any danger, though, explains Andrew Cheng, the NEAR project scientist: "We chose to fly over an area of the southern hemisphere where, if we were off-target, the uneven gravity of the irregular asteroid would actually kick us back into a higher orbit."Compared to a commercial airliner, NEAR traveled slowly through Eros's weak gravitational field: Its maximum speed was only 23 km/h. The flyover has gone as planned and the spacecraft is heading back to a higher orbit. While the dangers from skimming so close to Eros were slight, the potential rewards were great. "One of the mysteries we've encountered on Eros is a curious deficiency of small craters," says Cheng: "Something seems to be obliterating impact features smaller than a few tens of meters across." On worlds that are peppered with impact scars (like the Moon or Mercury) there are always many small craters for each large one. That's true on Eros, too, but images of the asteroid collected during the first 8 months of the NEAR mission reveal fewer small craters than researchers expected. On Earth small impact scars wear away because of weather, but there is no weather on airless Eros - some other process must be at work. "The high-resolution pictures we captured today will show these small scales very clearly," says Cheng: "They may give us some hints about what's going on." While Eros seems to be running low on diminutive craters, it boasts a surprising surplus of boulders. The surface of Eros is littered with 10- to 20-meter wide boulders, many more than one would expect by simply extrapolating the number of large boulders to smaller sizes. "This is telling us that there's something funny about Eros's cratering history in the 'recent' geological past," says Cheng. Four months from now, NEAR Shoemaker will be poised to record an even closer view of Eros. "We're considering landing on the asteroid at the end of NEAR's one-year mission," says Cheng. "The spacecraft would touch down near the south pole of Eros where the rotational surface velocity is low." Fans of Arthur C. Clark's science fiction novel "Rendezvous with Rama" might recall that explorers in that story landed near the pole of an asteroid-sized cylindrical spaceship, a spinning behemoth about the same size and shape as Eros. They chose to touch down near Rama's spin axis for the same reason that NEAR would settle near Eros's south pole: It's easier to land where the ground is moving slowly. Mission scientists are still reviewing various end-of-mission scenarios and expect a final decision on whether the spacecraft will land and how by the first week of December.
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| The "outer edge" of the Solar System?Our solar system may have an outer "edge" just outside the orbit of Pluto: A deep survey of Kuiper Belt Objects has turned up not one object with an orbit that keeps it permanently farther away from the Sun than 55 Astronomical Units. These observations, in 1998 and 1999, were sensitive enough to see a 160-km Kuiper Belt Object to at least 65 AU. 24 new Kuiper Belt Objects were found, 9 of which are 160 kilometers or bigger, but the most distant is near the outer limit of Pluto's orbit: This is the strongest evidence yet that more distant objects are missing. Since the discovery of the first KBO in 1992, more than 300 of these bodies have been found (see the sidebar for a big one), but it seems now clearer than ever that some event stripped away most of the planet-building material beyond 50 AU.Some of the known Kuiper Belt Objects as well as many comets are on elliptical trajectories that will carry them well beyond the orbit of Pluto (which ranges between 30 and 50 AU), but these are all believed to have formed inside Pluto's orbit and then been pushed outward by an encounter with Neptune or another planet. There are still no known objects which appear to have been created outside Pluto's orbit. So astronomers are left to wonder what explains this apparent edge: was the primordial solar system originally "small"? Or were there once more distant objects that were pulled away by the gravity of a passing star? Astronomers at telescopes around the world are currently conducting further surveys in an effort to learn more about the history of our solar system.
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LIGO establishes "first lock"Scientists from the Laser Interferometer Gravitational-wave Observatory (LIGO) have established "first lock" - this operational milestone marked the first time that the LIGO detector at Hanford, Washington, has simultaneously sent laser light back and forth along its two arms, thereby achieving the delicate optical interference that will make the detection of gravitational waves possible: Berkeley Press Release, First Lock special pages, APOD.Why are there no planets in the globular cluster 47Tuc?In the first attempt to systematically search for "extrasolar" planets far beyond our local stellar neighborhood, astronomers probed the heart of a distant globular star cluster and were surprised to come up with a score of "zero", as already reported in Update # 193 story 3: STScI, Space.com.Doubts about the planetary nature of many "exoplanets" detected with the radial velocity method have been raised by Hipparcos astrometry - a strange result of work in progress that raises more questions than it answers. Searching for other Earths: Berkeleyan. The 100th Ariane 4 has launchedEurope*Star F1 on Oct. 28 which will be used for a variety of communication services: SpaceViews.SeaLaunch has lifted the world's heaviest commercial communications satellite on Oct. 21 - Thuraya-1 has a mass of 5108 kg: SpaceViews. |
Save old astronomical plates!"The time domain is under-exploited in an astrophysical context," says a group of astronomers, "because the large photographic plate collections are almost never consulted by young astronomers" - great efforts would be justified to make these collections more readily available: paper by Brosch & al. and a New Scientist article.
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Compiled and written by Daniel Fischer
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