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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 |
SOHO as a comet hunter: SpaceScience. The current sun spot group # 9077: Taustrup's pictures. Also check the ALPO Solar Section - and the Solar Forecast (there could be aurora activity)!
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Zvezda in orbitIn the end everything happened on time: A Proton-K rocket has carried the Zvezda module into a low Earth orbit early on July 12, where it will be met by the International Space Station on July 26 (at 0.44 UTC, according to newer calculation). All appendages of Zvezda have been deployed properly within hours, and that all is well with the spacecraft. The reason for its two-weeks cruise: Zvezda has to be checked out thoroughly, because it carries only fuel for 2 (or at most 3) autonomous docking attemps with its automatic "Kurs" system. If they all should still fail, Russia has a contingency plan: A cosmonaut crew of 2, "Expedition Zero", is ready to go up in a Soyuz around Aug. 10 to dock with Zvezda and install an alternative docking system, Toru.
If Zvezda's launch and docking (set for about 1:10 UTC on July 26) are successful, the construction process of the Space Station will finally take off: There would be a Progress supply flight in late July, two more shuttle visits on Sept. 8 and in early October (the latter bringing the Z-1 truss with critical gyros for station attitude control), then the Soyuz launch of the first crew ("Expedition 1") on Oct. 30 (or more likely in November or December), followed by another shuttle mission - and some 9 missions more in 2001, the highest flight rate in years. If Zvezda's July 12 lauch should be delayed, there would be 2 more windows on July 14 and 16 and then more from Aug. 6 to 14: The determining factor are good lighting conditions during the rendezvous between Zvezda and the other ISS segments - which will be particularly exciting because there won't be continuous radio contact with the ground. After docking, the ISS will have grown to 35 meters in length and 69 metric tons. And it will have the first European contribution: Zvezda's brain, the Data Management System, is Made in Germany - and more modern than the computers on the U.S. modules. (AW&ST of July 10, p. 28-30) |
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Do pulsars lie about their ages?It was one of the few things that seemed sure in astrophysics: You can calculate the age of a pulsar, the spinning remnant of a supernova explosion, from the tiny amount by which that rotation slows down over time. But now the pulsar B1757-24, located in a bizarre supernova remnant widely known as "The Duck", might cast doubt on the well-established procedure: It has finally been possible to measure its proper motion (speed in the sky) - and it turns out to be way too slow. The pulsar is located far off the center of the supernova remnant, and to have travelled there in the 16 000 years given by its spindown age, it should have a speed of some 1600 km/s. The proper motion, however, gives a speed of at most 600 km/s: The age, it seems, is much higher than the spindown value.For years, astronomers have estimated the age of a pulsar by measuring the rotation period and the tiny amount by which that rotation slows down over time. The neutron star's powerful magnetic field acts as a giant dynamo, emitting electromagnetic radiation as the star rotates: That loss of energy slows the star's rotation, according to the standard theory used for nearly three decades. A calculation based on the neutron star's rotation period and its rate of slowing produces what astronomers call its "characteristic age," which has been presumed to be the true age - but that presumption now is called into question. With the large difference between B1757-24's "characteristic age" and the age required by the new VLA measurements, "this pulsar has been lying to us about its age," confused astronomers now say... |
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ISO detects a new molecule in interstellar spaceESA's infrared space telescope has one again detected a new molecule in the clouds of gas and dust in the space amid the starsL the methyl radical CH3, a 'free radical' which is one of the most important tracers for the formation of complex carbon-based molecules. CH3 is an intermediate product in reactions leading to the production of hydrocarbons - on Earth, for instance, it intervenes in the synthesis of all petroleum derivatives, which are hydrocarbons. CH3 is called a 'free radical' because of its extremely reactive nature: It combines very easily with other molecules, and in fact in the labs on Earth its study is very difficult because its lifetime is only a few millionths of a second.The abundance of CH3 that ISO's Short Wavelength Spectrometer has detected in a cold molecular cloud near the Galactic Center (along the line of sight to Sgr A*) poses new problems however, since there is actually much more CH3 than predicted by the traditional models describing molecular clouds: The chemical models apparently aren't precise enough yet. During its mission (that is long over) ISO has observed a wealth of molecules in space, both in the gaseous and solid form, e.g. water, ices and crystalline silicates. The methyl radical CH3 itself was detected extraterrestrially for the first time by ISO on Saturn and Neptune in 1998 and 1999 respectively. |
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The first X-ray flare from a Brown Dwarfhas been observed by Chandra - a discovery that has implications for understanding the explosive activity and origin of magnetic fields of extremely low mass stars. Chandra detected no X-rays at all from LP 944-20 for the first nine hours of a twelve hour observation, then the source flared dramatically before it faded away over the next two hours. "We were shocked," says a scientist: The energy emitted in the brown dwarf flare was comparable to a small solar flare, and was a billion times greater than observed X-ray flares from Jupiter. The flare could have its origin in the turbulent magnetized hot material beneath the surface of the brown dwarf. A sub-surface flare could heat the atmosphere, allowing currents to flow and give rise to the X-ray flare -- like a stroke of lightning. |
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NEAR's descent has begunA burst from its thrusters on July 7 has sent NEAR Shoemaker on a weeklong descent toward its closest look yet at asteroid Eros. At 18:00 UTC, the spacecraft flawlessly performed a 20-second engine burn on commands from the NEAR Mission Operations Center. The first orbit correction maneuver since April 30 nudged NEAR Shoemaker from 50 km above Eros toward lower vantage points 35 km from the asteroid's center and - at times - less than 19 km from its ends. Flying around a peanut-shaped space rock is still a tricky business, but the risks lessen as NEAR Shoemaker's navigators learn more about Eros' size, shape and rotation."Now that we have a better read on the asteroid, our ability to predict where we're going is much better than it was earlier in the mission," says Bobby Williams, who heads the NEAR navigation team at NASA's JPL. Once NEAR Shoemaker reaches the 35-km orbit on July 14, the NEAR team will spend four days reassessing the asteroid's gravity field. The 10-day orbit also includes plans to take high-resolution images of the surface, refine estimates of the asteroid's mass and density, gather additional data on the asteroid's elements and continue searching for a magnetic field. |
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This is a rare month with three eclipsesThe last time that two (partial) solar eclipses and one (total) lunar eclipse happened in the same calender month as they do in July 2000 (on the 1st, 16th and 31st) was in December of 1880 and before that in January 1805 - and it won't happen again until Dec. 2206, Jan. 2261 and Nov. 2282. Months with one solar and two lunar eclipses are equally rare: The last two were in 1904 and 1817, the next three will be in 2219, 2284 and 2295. (Calculations by F. Espenak)Another meteorite has been found after the May 6 bolide (see Update # 190 story 4): The 330 gram stone was picked up on May 25 in 3 km distance from the 214 gram piece that had been found immediately after the fireball; both were found in the Czech Republic, not Poland, BTW. (Meteoros 6/2000 p. 98-9; see also a Czech article with pictures and this picture of a smoke cloud the bolide had left behind) Electrophonic sound from a fireball has been heard widely after a major meteor event in the U.S.: Space.com. "Space sails" pushed by photons in lab experimentNASA scientists have beamed microwaves and laser energy to "fill" lightweight sails in laboratory demonstrations of how these technologies might provide propulsion for interstellar exploration - the sails used in the microwave experiment were actually driven to liftoff and flight, while the laser-driven sails achieved horizontal movement, and the experiments are the first known measurements of laser photon thrust performance using lightweight sails that are candidates for spaceflight: JPL Press Release, Microwave Sciences info, CNN, SPIEGEL, SpaceViews.Also: NASA Science News and LA Times Magazine on solar sails in general and Space.com on Laser Lightcraft, a different approach. |
CHAMP, Cluster remain set for July 15The launches of the small German geophysics satellite and the first two replacement Cluster satellites all remain set for July 15, at 12:00 and 12:40 UTC: CHAMP Homepages at DLR and GFZ plus a WELT article. Cluster: Baikonur diary (with many pictures), Space.com on the mating to the booster and ESA Science News on the final go.Balloon flight test UV background detectorThe NIGHTGLOW experiment, now tested in Texas, will eventually measure the night sky's UV glow during an Antarctic mission - a little-studied background that could compromise attempts to measure the Cherenkov radiation from ultra-high energy cosmic rays with a satellite camera: NASA Science News, NIGHTGLOW Homepage and the satellite idea, plus an RP story.80 km crater found on EuropaImpact craters with diameters of 20 kilometers and larger are extremely rare on Jupiter's moon Europa; as of 1999 only 7 such features were known - so the discovery of an 80 km impact structure raises new questions about the age of Europa's surface: PhotoJournal, BBC story. Also: Fla. Today on the upcoming 5 month joint observations by Cassini and Galileo and Spaceflight Now on the difficulties of hearing Pioneer 10 over 11 billion km distance.
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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
