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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion! (SuW version) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
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Mir history after textbook de-orbiting15-year-old complex performs all braking burns flawlessly / Spreading fragments provide sky show over Fiji / Visual observers way ahead of mission control pros in confirming successBy a strange twist of fate the fiery demise of the Mir space station could be observed perfectly - and safely - from solid ground. "I was walking along the beach looking at the sky and the streaks started to move across," Alex Bowles in Fiji told the Australian Broadcasting Corporation: "As it came over the horizon you could see this firey-blue glow like magnesium burning and as it passed overheard it started to break up, splitting up into maybe five or six separate stars that just kept shooting along on the same projectionary, moving right across the horizon." In contrast no one on the fishing vessels in the splash-down zone that had made many headlines before has reported seeing anything (due to bad weather and being too far East). The news about the success of the two chartered observing planes were confusing in the next two days - with SpaceRef reporting that "the folks who paid a substantial sum to be in an airplane near the expected impact site were apparently too far away to see anything," while the expedition organizers said that they had "witnessed an even more spectacular show [than Fiji] as Mir swept in hard, fast and fiery." |
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Reality was right
inbetween, it turns out. "Both planes did see something," reports C. Miller:
"The biggest plane (which I was on) was farther away, and had the the worst view.
(The information we had was that the last burn would have a delta-v of 20
meters/second. It was actually 30 meters/second. It was very hard to predict
how long the Progress engines would burn. The difference in the delta-v altered
the best viewing site by about 2000 kilometers.)[...] The second smaller
plane was between the bigger plane and Fiji. It was mostly staffed by teenagers
with digital video recorders. We all expected this plane would have the worst
view. However, three teenagers [...] actually turned out to be the heroes of
the expedition. They recorded evidence of explosions, plus parts breaking off." In any case "the people on Fiji had a better view", acknowledges Miller - and their visual reports (first aired on CNN at 5:49 UTC) were a clear confirmation that the 3rd de-orbit burn had been a full success. At the same time the (now former) flight controllers near Moscow could still only guess that they had done everything right.They had: All three burns of the Progress engine (starting at 0:32, 2:00 and 5:07 UTC) had taken place without any problems, then Mir had left the range of the last ground station. The last to see the space station intact were Japanese astronomers who captured detailled video images of the still intact station. When the station's fragments finally reached Fiji, the pattern of some 6 bright spots with smoke trails was reminiscent of the decaying Skylab in 1979. Now the wait is on whether any of the debris will wash ashore at some remote island. Contradictory timelines for Mir's suicide burnsMission Control on March 21 was uploading into the Progress' computer commands that will tell the ship's engines to fire the first of the 3 braking impulses at 00:33 UTC on March 23; this impulse will last some 20 minutes. The second impulse, which is also to last 20 minutes, is scheduled for 02:02 UTC, and the third and final impulse will begin around 05:30 UTC and last some 23 minutes. Another source gives 00:32, 02:01 and 05:08 UTC as the beginning times of the three, burns, however, with Mir reaching 100 km at 05:44 UTC, 80 km at 05:52 UTC (destruction begins) and 06:00 UTC as the calculated impact time of unburned fragments. The ellipse dissipation centre coordinates of unburned fragments are now given as 44.2 deg. south latitude and 150.0 deg. west longitude.Mir de-orbiting now set for March 23rdMission control has now pretty firmly set the times for the final burns to drive Mir into the atmosphere: The first one will come on 0:33 UTC on March 23rd, the second one at 2:00 UTC and the third one will follow at some point after 5:00 UTC, when the new orbit is better known. Impact of Mir's fragments into the Pacific is expected at 6:20-6:30 UTC, just six hours after the braking maneuvers have begun. Only if the activity of the Sun should change very suddenly and affect the atmosphere greatly the timeline would be calculated anew. The orbit is decaying now already 3 km/day, and the critical altitude of 220 km will be reached on March 21 or in the 48 hours after that.
Meanwhile Taco Bell is offering a free taco to everyone in the United States
if the core of the Mir space station hits a floating Taco Bell target placed
in the South Pacific. The Mexican-style quick-service restaurant chain
has created a 40 by 40-foot target, painted with a Bell bull's-eye and bold
purple letters stating: "Free Taco Here." The floating target will be placed
in the South Pacific Ocean off the coast of Australia in advance of Mir's
descent. If the core of Mir hits the designated Taco Bell target upon its
re-entry, every person in the United States will have an opportunity to
obtain a coupon for a free taco, valid at participating Taco Bell restaurants.
The company has purchased an insurance policy to cover the anticipated cost of the
free taco redemption should the core of Mir hit the target...
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"First fringes" for the Keck and VLTI Interferometers just five days apart!On March 12th, astronomers on Mauna Kea won a tight race with their colleagues on Paranal: They succeeded for the first time in combining the light of the two 10-meter telescopes coherently, producing interference fringes (they had obtained fringes with 50-cm siderostats on Feb. 22nd already). This is just the first step in activating the Keck Interferometer, but it can already be hoped that the first scientific results might be obtained in the fall. Just 5 days later the Very Large Telescope Interferometer got its First Fringes as well, though only with little siderostats at this time; the 8-meter telescopes should come into the loop late this year. While optical interferometers have been around (and producing science results) for decades, esp. in the 1990's, the Keck and VLTI interferometers will be the only ones employing huge telescopes with much light-gathering power, and in the case of the Keck Adaptive Optics are used to straighten out the atmospherically distorted wavefronts from the stars. |
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Plan for Galileo's final years detailedNASA has finally unveiled its plans for the extended extended extended mission of its durable Jupiter orbiter: five more flybys of the Jovian moons before a final plunge into the crushing pressure of the giant planet's atmosphere in mid-2003, 7 1/2 years after entering orbit.
Jupiter's radiation belts are harsherthan expected: Radio measurements from NASA's Cassini spacecraft indicate that any future spacecraft venturing very near Jupiter would be zapped by the radiation belts there even more severely than had been previously estimated, with the harshest radiation within about 300,000 kilometers of the giant planet. |
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Tharsis rise the key to Martian mysteries?The Tharsis rise in Mars' Western Hemisphere is key to many of the Red Planet's mysteries, including its large-scale shape and gravity field, and its early climate and water distribution - an enormous load of volcanic material emplaced at the Tharsis rise caused global changes to the planet's lithosphere, creating many key features in the landscape: WUStL Press Release, SC.How the MGS is changing our view of Mars, from evidence of greater explosive volcanic activity in Mars' past to the increasing likelihood of finding Martian life today: SC. Hemative the key to the mystery of elusive Martian water? Science@NASA. Can liquid water exist on Mars today? SD. The ALH84001 debate: SN. MPL not clearly located on MarsContrary to earlier rumors, the ongoing search for the Mars Polar Lander in MGS images "is extremely challenging and has thus far produced no definitive conclusions," according to a March 26 NASA/NIMA Press Release, SN, FT. Earlier: CNN, SC (earlier), AN, ST, NYT, AP, SPIEGEL.2001 Mars Odyssey previews: Homepage, JPL Release, Science@NASA, SC ( earlier), FT, CNN, Reuters. A European Mars Sample Return? SC, CNN. Japan announces Venus mission for 2007The Japanese space agency ISAS will build a 20-billion-yen spacecraft for a spring 2007 launch to Venus - after arrival in 2009 it is to observe the planet with IR and UV cameras. (AW&ST of March 26, p. 23)Venus is in inferior conjuction now, but far North of the Sun: observations by WAA, a computer simulation by Brinkmann and the NYT (earlier) and SC on the unusual constellation. Plus Venus hemispherical globes. Stardust's optics coat up againIn December Stardust partially cleared a coating that was clouding its camera optics by applying heat, but now the coating is back - perhaps its can be cleaned again, using the same heating technique: JPL Release.Deep Space One has received new software for its comet Borrelly encounter in September: JPL Release, Mission Log. Contract for Deep Impact instrument: Rockwell Press Rel. XMM saw X-rays of comet McNaught-Hartley and got fine spectra: ESA Science News; also a nice picture of the comet.
Yet another asteroid moonThis time it circles around (107) Camilla, and the HST found it: IAUC, SD, Astronomy.A hypothesis to explain Eros' many boulders invokes a strange mixing effect: Astronomy. How future ESA missions will hunt for NEOs, namely GAIA and BeppiColombo: ESA Science News. |
White Dwarfs a major Dark Matter component?In digitized sky images 38 previously unseen nearby cool white dwarfs have been discovered - if the density of these stars, apparently members of the galactic halo zooming through the disk of the galaxy, is indicative of the rest of the galaxy's halo, these dead stars would comprise at least 3 percent of the dark matter of the halo, and perhaps as much as 35 percent: Berkeley and Vanderbilt [EA] Press Releases, a related FAQ, coverage by SN, SC, BBC, AP, SF Gate, CSM, Reuters, SPIEGEL, RP.AMANDA detects the first high-energy neutrinosA novel telescope, buried deep in the Antarctic ice at the South Pole, has become the first instrument to detect and track high-energy (atmospheric) neutrinos - the AMANDA telescope array consists of 677 optical modules, arrayed on electrical cables set deep in the ice beneath the South Pole: U. Wisc. Press Release [EA], NSU, SC, Milwaukee JS, SPIEGEL.Studying Cosmic Rays with a balloon from Antarctica - how the Advanced Thin Ionization Calorimeter Scientific Balloon Experiment went: Louisiana State Univ. PR. India's GSLV didn't get farThe test launch of a high-powered Indian rocket was postponed indefinitely on March 28 after a technical snag forced its first flight to be aborted: SN, BBC, New Sci., AN, AFP, ST, Reuters, RP.Russia announces first satellite air-launches for 2003: SD. Radiation from newly born, ultra-bright stars burns a bubbleinto the nebula N83B - a turbulent environment typical of newborn massive star formation sites: paper by Heydari-Malayeri & al., ESA HST Release, STScI Release, Reuters, CNN, SPIEGEL.
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All other historical issues can be found in the Archive.
The U.S. site of this Cosmic Mirror has been visited
since it was issued (the German site has no counter).
Compiled and written by Daniel Fischer
(send me a mail to [email protected]!), Skyweek
