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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 |
30 years ago, Apollo 14: NASA's archive, SC articles 1, 2 and 3, and Zetetique.
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Predicted 'Transient Lunar Phenomenon' didn't comeFirst results coming in indicate that there was no anomalous brightening on the Moon on the morning of February 9th - a large international campaign had been mounted to observe the crater Torricelli B exactly one Saros after a strange brightening had been seen there in 1983. If that Transient Lunar Phenomenon (TLP) had been due to a strong reflection off an oddly shaped geological formation on the Moon, the TLP should have been visible again on Feb.9, which would have provided an explanation for the 1983 event and other similar TLPs - at least one class of these mysterious phenomena would thus have been explained. Now we are as wise as before ... |
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NEAR's descent to Eros' surface is nearThe time has come: The 4-hour descent of the first asteroid orbiter to the surface of that asteroid is scheduled to start at 15:31 UTC on February 12 with a maneuver moving it out of its current orbit 35 km from the center of Eros which corresponds to an altitude "above ground" of about 25 km. On the way down NEAR will take images that will help determine its exact location and altitude, and set the timing for the final four thruster firings that will slow the descent speed. NEAR Shoemaker will approach the surface on its side, its outward-facing camera pointed down, snapping a photo every minute. In the final 45 minutes, when the spacecraft is about 6 to 7.5 km from its landing site at the edge of the crater Himeros, the camera will begin taking a new image about every 30 seconds.At 19:16 UTC NEAR should be down to 5 km, at 19:31 to 3, and at 19:47 to 1 km above the surface. The last clear pictures from the telescopic camera, taken from approximately 500 meters, could show surface features as small as 10 cm across - obtaining these images is the main objective of the descent. Since last October, the NEAR imaging team has been puzzling over strange surface features of Eros seen in new, high-resolution images. There is the hope that the close-up images taken in the final few minutes before the spacecraft drops onto the surface will help to answer their questions about the geology of the asteroid. After that, NEAR mission operators will use the blurring photos, altitude data from the laser range finder, Doppler tracking and the eventual loss of signal to learn when the spacecraft touches down, predicted for 20:04 UTC. Deep Space Network antenna stations in Madrid, Spain, and Goldstone, Calif., will simultaneously cover the maneuvers. The whole sequence of engine burns has to go right, or it might not be a very soft touchdown: The unknown nature of the surface makes it hard to predict what will happen to the spacecraft, especially since it wasn't designed to land. The most flight controllers can hope for is a beacon from NEAR Shoemaker that says it's still operating. But the unique, pioneering mission will be over on Feb. 12, no matter what.
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Violation of standard model claimed - is supersymmetry around the corner?Scientists at the Brookhaven National Laboratory, in collaboration with researchers from 11 institutions have announced an experimental result that directly confronts the so-called Standard Model of particle physics. The Brookhaven finding, a precision measurement of something called the anomalous magnetic moment of the muon, deviates from the value predicted by the Standard Model: This indicates that other physical theories that go beyond the assumptions of the Standard Model may now be open to experimental exploration. "We are now 99 percent sure that the present Standard Model calculations cannot describe our data," says Brookhaven physicist Gerry Bunce, project manager for the experiment.The g-2 values for electrons and muons are among the most precisely known quantities in physics and have been in good agreement with the Standard Model. The g-2 value measures the effects of the strong, weak, and electromagnetic forces on the spin of these particles. Using Standard Model principles, theorists have calculated with great precision how the spin of a muon, a particle similar to but heavier than the electron, would be affected as it moves through a magnetic field. The scientists and engineers at Brookhaven, however, using a very intense source of muons, the world's largest superconducting magnet, and very precise and sensitive detectors, have measured g-2 to a much higher level of precision. The new result is numerically greater than the prediction. "There appears to be a significant difference between our experimental value and the theoretical value from the Standard Model," says Yale physicist Vernon Hughes, who initiated the new measurement and is co-spokesperson for the experiment. "There are three possibilities for the interpretation of this result," he says: "Firstly, new physics beyond the Standard Model, such as supersymmetry, is being seen. Secondly, there is a small statistical probability that the experimental and theoretical values are consistent. Thirdly, although unlikely, the history of science in general has taught us that there is always the possibility of mistakes." All physicists agree that further study is needed. And they still have a year's worth of data to analyze. |
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A lower age limit of the Universe of roughly 12.5 Gyr(1.25 x 10**10 years) +/- 25% has been determined from the first observation of uranium outside the Solar System. Thanks to the VLT's UVES spectrograph the amount of the radioactive isotope Uranium-238 and another radioactive isotope could be measured in a star that was born when the Milky Way was still forming. Although the stated uncertainty is still about +/- 3 billion years, this is only to a minor extent due to the astronomical observation. The main problem is the current absence of accurate knowledge of some of the basic atomic and nuclear properties of the elements involved.However, further laboratory work will greatly improve this situation and a more accurate value for the age of the star and thus a lower limit for the Universe should therefore be forthcoming before long. The latest analysis of 11 cosmological parameters, meanwhile, using both the fluctuation spectrum of the cosmic microwave background and the large scale structure of the distribution of galaxies in space is yielding a "best" value for the age of the Universe of 14.0 Gyr, with the value between 12.1 and 14.6 Gyr with a probability of 95% - that would fit. |
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Two colliding giant clusters of galaxieshave been discovered with the Australia (radio) Telescope: There is telltale 'wreckage' indicating that two giant clusters of galaxies have collided and merged. The resulting cluster is known as Abell 3667 and contains about 500 galaxies: It appears to be a large cluster that has run into a slightly smaller one. The key evidence is a pair of arcs of radio emission that straddle the cluster, 12 million light-years apart. The collision and its aftermath are like "the Titanic hitting an iceberg," says the discoverer, PhD student Melanie Johnston-Hollitt: "Afterwards you see only ripples and bits of wreckage, but that's enough to show that there's been a collision."Radio arcs of the kind seen in this cluster are very rare: The first ones found were thought to be ghostly remains of dead, dissipated galaxies, and were dubbed 'relics'. Theorists had predicted that galaxy clusters would free-fall together at thousands of kilometres a second, smacking into each other and producing huge shock waves in the thin hot gas that fills the space between the galaxies. In 1999 it was demonstrated that the shock waves would produce large arcs of radio-emitting particles on the outskirts of the cluster, like those of Abell 3667. Cluster collisions release the largest amount of energy in a single event since the Big Bang, 10**57 joules - and so they might explain one of the outstanding mysteries in astronomy, the origin of ultra-high-energy cosmic rays. |
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The Next Generation Space Telescope is shrinking againFirst it was supposed to have a main mirror of 4 meters, then NASA boldly expanded it to 8 meters - and now the agency is forced to again trim a meter to two of the mirror, thus losing 10 to 15 % of the NGST's science capabilities: The Hubble successor was just too ambitious. In the process of restructuring the program - which is the most important big new observatory America's astronomers want (see Update # 190) - a plan for a smaller flight demonstration of a collapsible mirror (see Update # 193 small items) has been cancelled already. But that may also mean that the NGST could be launched as early as late 2008, allowing for more parallel observing with the HST. (Space News of Jan. 29) |
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Brown-dwarf-like remnants in two binary systemshave been discovered in the cataclysmic variables LL And and EF Eri: These small, cool stars look superficially like brown dwarfs but are actually the remnants of ordinary stars that have been whittled down to cool Jupiter-sized bodies over billions of years by spilling material over to a white dwarf companion star. In the case of LL Andromedae, the signature of methane was detected at a wavelength of 2.2 microns: This shows that the donor star's temperature is around 1300 Kelvins, similar to a 'T-type' methane brown dwarf. In EF Eridani, the donor star is a little warmer at around 1650 K, similar to an 'L-type' brown dwarf. According to theory, the estimated mass of these cool stars is near four hundredths the mass of the Sun, or 40 times the mass of the planet Jupiter. The two star systems are roughly 100 and 130 light years away - virtually neighbours of the solar system. |
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Do magnetic fields shape many planetary nebulae?For a quarter century, the so-called planetary nebulae are thought to be formed when a slow wind from the progenitor giant star is overtaken by a subsequent fast wind generated as the star enters its white dwarf stage. A shock forms near the boundary between the winds, which creates a relatively dense shell that provides the characteristic appearance of a planetary nebula. A spherically symmetric wind will produce a spherically symmetric shell, yet over half of known planetary nebulae are not spherical; rather, they are elliptical or bipolar in shape. While a magnetic field could launch and collimate a bipolar outflow, the origin of such a field has hitherto been unclear, as previous work suggested that a field could not be generated.But now it has been shown that an asymptotic-giant-branch (AGB) star can indeed generate a strong magnetic field, in a dynamo at the interface between a rapidly rotating core and the more slowly rotating envelope of the star. The arrangement of differential rotation and convection in adjacent layers in this star is similar to that in the Sun and strongly suggests the possibility of an "alpha-omega" interface dynamo. The field - for which there is no direct observational evidence in planetary nebulae yet - seems to be strong enough to shape the bipolar outflows seen so often in planetary nebulae. Magnetic braking of the stellar core during this process may also explain the puzzlingly slow rotation of most white dwarf stars. (Blackman & al., Nature of Jan. 25, p. 485-7) |
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Mass of the Oort cloud 10 times smaller?Recurring collisions between comets during the solar system's formation may have ground smaller comets to bits, leaving only big comets larger than 20 km to survive and end up in the Oort cloud, according to a new model - the cloud may thus be 10 times less massive than previously thought. By studying comets of different sizes, its was predicted how the comets would collide with each other while still residing among the planets, and how the collisions would erode the comets' nuclei: The model showed that comets with nuclear diameters smaller than 20 km would have been destroyed in the early solar system's demolition derby. Previous Oort cloud formation models had neglected the effects of these collisions. Another apparent implication of this violent collisional environment is that the comets in the Oort cloud could be smaller than previously thought: If comets were so eroded that they would never have left the region of the giant planets, then few of them would have survived to be ejected to the Oort cloud. (Stern & Weissman, Nature of Feb. 1, p. 589-91) |
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ISS UpdateAtlantis has docked to the ISS on Feb. 9, following a spectacular launch! Meanwhile the tug-of-war over Tito's ride to the ISS continues, while his training has resumed ... NASA, LockMart, MSFC and Alenia Spazio Press Releases, the Mission Status Center, the Flight Plan, the MCC Status Reports # 4, 3, 2, 1 and coverage of Feb. 9: SN (earlier), CNN, SC ( other story), BBC, AP, Reuters, AFP, AN, RP. Feb. 8: Ralph M. Hall Press Release, Interfax, AN, Reuters, NYT, SPIEGEL (with another cool picture). Feb. 7: SN (with a stunning launch picture), SC ( earlier), FT ( earlier), BBC, HC, AN, Reuters, FT, CNN (plus a chat), AFP. Feb. 6: CNN, NYT, FT, HC, SC ( other story and another one), SD, MSNBC. Feb. 5: BBC, SC, AN, CNN, FT. Feb. 4: SN (very long preview of STS-98 - 40 K text!), FT, BBC. Feb. 2: CNN, Disc., AFP, SC, ST. Feb. 1: SN, AN, FT, SC. |
Mir's sinking an average of 500 to 750 meters a day; the deorbiting will
shift to beyond March 8, however, for celestial mechanical reasons. Meanwhile
in Russia some resistance against the deliberate destruction of Mir remains,
while nthusiasts want to charter an airplane to watch the crash close-up.
A chronology for 2001 and coverage of Feb. 9: BBC, SC, AFP. Feb. 8: Newsday, Reuters [Wired], AFP. Feb. 7: Interfax. Feb. 6: Reuters. Feb. 5: BBC. Feb. 4: SC. Feb. 3: SD. Feb. 1: SN, Interfax. Houston's Outpost tavern faces uncertain future - the famous bar near the JSC is struggling: a HC story and an Outpost fan page. The Shenzhou II news blackout continues, but officials say everything's fine: SD, AFP. First yuhangyuans to fly "early in this century," state media say: AP. |
Cluster cleared for scientific operationsThe unique mission of the 4 European Cluster satellites formally got under way on Feb. 1 when the ESA Commissioning Review Board gave unanimous approval for the start of scientific operations - for the next two years, 4 identical spacecraft will be returning simultaneous observations as they follow highly elliptical polar orbits around the Earth, obtaining the first detailed 3-D view of near-Earth space: ESA Science News.Lunar Orbiter Atlas onlineThe Lunar Orbiter Photographic Atlas of the Moon is the definitive reference manual to the global photographic coverage of the Moon - now this work is available as a digital archive with the complete set of 675 plates, enhanced to display the best photo quality possible: LPI Press Release.One year after launch, student satellite still flying highAgainst all odds, the first satellite designed and built entirely by Stanford students is still sending data on its first anniversary in space - OPAL (see Updates # 170 story 3, 172 story 7 and 174 story 6), the Orbiting Picosatellite Automated Launcher, was launched aboard an Air Force rocket on Jan. 26, 2000: Stanford Press Release and OPAL Operations page.NASA hopes space radiation kills electronics - in the space Radiation Electronics Testbed, a payload now orbiting Earth aboard a satellite called the Space Technology Research Vehicle 1-d, launched last November: AN. |
Towards solving the Huygens problemA special calibration test is being conducted with the Huygens receivers on board Cassini - the results will provide a solid engineering basis for the design of new mission scenarios which can recover the Huygens relay link: ESA Science News.Some new Cassini images and a movie have been released, showing Io in Jupiter's shadow and Jovian aurorae: PIA 028... 81, 82, 83, Imaging Diary. The first issue of a new newsletter for Io fans is now available! Is Europa a wet Io? SC. The dark side of Iapetus may be a 'gift' from another Saturn moon, Titan: NSU, SPIEGEL. Webcam catches mishap near Mars probeWhile checking webcam images from the clean room at the Cape on the evening of Jan. 19, Ron Baalke noticed something quite out of the ordinary, and his quick reaction has helped to save the Odyssey project a major headache: JPL Universe. What the THEMIS instrument might accomplish: Science@NASA.What's Mars doing? Here are the latest amateur results, from Japan, Portugal and Florida.
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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
