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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion! (the latest updates) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
Evening Show in April: NASA Science News, Sky & Tel., Astronomy, Discovery, CNN, Space.com, BBC, EZ. Invisible 'massing' in May: Griffith Obs., Space.com, AP.
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Cosmonauts enter station while MirCorp announces continued funding and another launch!Mir is a manned space station again after the crew of Soyuz TM-30 had performed a manual docking early today - and hours later MirCorp, the company that is paying for the current trip, announced that it would be able to fund the operations of at least until the end of this year. "Our investors reaffirmed their commitment to Mir's commercialisation with a substantial amount of money for the second round of financing," MirCorp's head Jeffrey Manber has said: "This commitment will allow the new mission later this year which will include establishing the first ever Internet portal in space." This next mission is set for September. While the Soyuz was on its way, another company official had said that "MirCorp is not offering ad-hoc flights to the station, but will provide a service that for the first time is built on a comprehensive and compelling strategy to successfully commercialize Mir."
New mission to Mir has begun, but station's future stays cloudedThe launch of two cosmonauts to the space station Mir on the morning of April 4 has already made history: For the first time ever a manned space mission has been paid for completely out of private funds! While the Russian duma (parliament) has in principle provided some money to Energia to continue running the station, none of that has arrived so far - and the flight of the Soyuz TM-30 craft is being paid for in full by MirCorp, the Netherlands-based company that has leased Mir and wants to turn it into the first commercially-run space station.But the prospect of a fiery reentry as early as this summer still hangs over the 14-year old station: MirCorp must raise more money until the end of this month and and convince Energia (and eventually the Russian government that has the ultimate say) that the prospects are bright for the future. So far MirCorp's announcements about what it hopes to do with Mir are rather vague and "range from industrial production and scientific experimentation to space tourism and in-orbit advertising," although top business consultants are right now looking at the business plan. The mission of commander Sergei Zaletin and flight engineer Alexander Kaleri had originally been set for 45 days, but since they are not accompanied by movie actor Vladimir Steklov, their resources last longer, and the mission has already been extended to 60 days (and could in principle last up to 90 days). The first task is looking for a small but significant leak somewhere in the station (with sophisticated equipment) and fixing it, then perform more than 50 scientific experiments. More equipment for the latter is to arrive later this month on a Progress freighter. This very freight ship, however, will also decide the fate of Mir: It will carry enough fuel to either raise Mir's orbit (so that it isn't affected too much by friction in the upper atmosphere) - or to start the controlled reentry. The decision has to be made before the ship is launched, as its engines have to be configured accordingly. So, in the case that MirCorp cannot find new investors (or more cash from the present ones), Zaletin and Kaleri could very well find themselves im May preparing Mir for its demise in August or September. Otherwise MirCorp plans the next mission for September, perhaps even with its first 'space tourist.' Then there is the mysterious 'Chinese card': Persistent rumors say that China either intends to buy the complete Mir station or at least rent it (with whatever role remaining for MirCorp). China has often declared its desire to have a space station of its own and could use Mir at least for practice. And finally there are other rumors among Russian space officials that the Russian government might soon take back control of Mir - and some veteran cosmonauts have said that they would rather fly there than serve on the ISS under American command... |
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Ulysses flew into Hyakutake's tail - 560 million km from its head!Only now have scientists with the ESA interplanetary probe Ulysses understood strange readings of the solar wind the spacecraft had recorded on May 1st, 1996: The explorer had, by pure chance, passed through the tail of the famous comet Hyakutake - but at a distance of half a billion kilometers from the comet's head where no effects from the comet had been expected anymore. Apparently comet tails stay relatively well-defined entitites even way beyond the point where they no longer emit light. This unexpected 'in-situ' study of a comet's distant tail is already advancing the field - and could even explain some 'impossible' visual tail length estimates reported 4 years ago.Ulysses recorded the comet tail's effects in two ways: through changes in the interplanetary plasma and of the magnetic field. The solar wind, which usually blows past the spacecraft at about 700 km/s, became strangely hot and calm, and the number of charged particles encountered by the spacecraft soared at precisely the same instant, about 1000-fold. This disturbance lasted for only a few hours, but at precisely the same time the magnetometer aboard Ulysses reports that magnetic field lines were altered in a fashion characteristuc for a comet encounter. As no known comet was near, this explanation was discounted until the Hyakutake connection became apparent. Comets' ion tails are generally thought of as pointing almost straight away from the Sun. The magnetometer data from Ulysses, however, reveal that at the spacecraft, the tail was definitely not doing this: It was travelling almost sideways. The likely explanation is the comets quick motion around perihelion: Like the jet of water from a lawn sprinkler, Hyakutake's tail started out pointing away from the Sun. The further it got from the Sun however, the more it twisted away from the anti-sunward direction, as a lawn sprinkler spray twists. Ion tails are therefore curved, especially when comets are around perihelion. This has implications for some Earth-based comet observations: A few weeks before Ulysses's tail crossing, some observers reported tail lengths for Hyakutake that were much longer than possible if comet tails are assumed to be straight, and pointing away from the Sun. The Ulysses magnetic field measurements show that these assumptions aren't true! Although it can't quite fully account for some of the longest tail lengths reported in late March and early April 1996, Hyakutake's tail would have been curved in the correct way around the Earth for observers to see a tail longer than previously thought possible. Not only did Ulysses show that comet tails are longer than anyone realized: This data is significant just because it's only the fourth time anyone has directly sampled the contents of a comet like this (the other comets studied in-situ are Giacobini-Zinner in 1985, Halley in 1986 and Grigg-Skjellerup in 1992). Ulysses is equipped with spectrometers, instruments that can identify chemicals: Hyakutake's tail was found to be mostly carbon and oxygen with some nitrogen, and water. |
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Gas deep inside Sun speeds up, slows down, in 16 month rhythmYet another strange discovery by helioseismology, the art of studying the interior of the Sun by analyzing sound waves travelling through it and expressing themselves at the surface: Currents of gas deep inside the Sun pulsate like the blood in human arteries, speeding and slackening every 12 to 16 months. A periodicity or quasi-periodicity of thus timescale has never been noted in the Sun before, but it could be closely linked to the dynamo. The new result comes from pooling observations from the MDI instrument on the SOHO spacecraft and from a worldwide chain of ground stations called GONG.The flows of gas under study occur about 220 000 km beneath the visible surface, or almost a third of the way down to the center of the Sun. Here is the supposed dynamo region where the turbulent outer region, the convective zone, meets the orderly interior, or radiative zone. The speed of the gas changes abruptly. Near the equator the outer gas travels around the Sun's axis of rotation faster than the inner gas. At mid-latitudes and near the poles, the outer gas rotates more slowly. The news from MDI and GONG is that the contrast in speed between layers above and below the supposed dynamo region can change by 20 per cent in six months. Apparently there is a regular exchange of angular momentum between the layers. When the lower gas speeds up, the upper gas slows down, and vice versa. In observations spanning 4.5 years, from May 1995 to November 1999, these alternations in speed occurred three times. They indicate a heartbeat of the Sun at one pulse per 15-16 months in equatorial regions, and perhaps faster at higher latitudes. There may also be a link between the deep changes and another remarkable phenomenon seen by helioseismologists nearer the surface: At depths down to 60 000 km, bands of gas parallel to the equator move slightly faster or slower than the average speed for their solar latitudes. Although the effect is subtle, it is very persistent, and the scientists see the bands of fast and slow gas gradually moving from high latitudes towards the equator, as the years go by - just as many features on the solar surface do. |
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"Planet" TMR-1C all but retractedThe temperature of the controversial object (see Update # 81) has now been measured at 2700 Kelvin - "hotter than the predicted temperatures of young giant planets," according to the researchers who had offered the planet interpretation but now feel that "the results remain consistent with the explanation that TMR-1C may be a background star": abstract and Special Page, a NASA Press Release (Spacefl. Now version) and coverage by AP, SpaceViews, Discovery, Space.com, CNN.Spectacular Hubble image of a Planetary Nebula, NGC 6751: STScI Press Release, Space.com, BBC, EZ, Spaceflight Now.
Goldin takes full responsibility for Mars troubleNASA Administrator Daniel Goldin took full responsibility on March 29 for last year's botched Mars missions, a day after reports were released blaming the failures on mismanagement, unrealistic expectations and not enough money: full speech, excerpts, AP, Fla. Today, Space.com, SpaceViews stories.How the likely MPL cause of death was found - the software glitch that likely doomed the Mars Polar Lander would have done the same to NASA's next spacecraft to alight on the Red Planet had the problem not been uncovered by accident: Space.com. The software error was striking - in how obvious it was: Space.com. German scientists frustrated by delays in Mars missions on which they wanted to fly experiments: BdW. Mixed reactions to the MPL reports in House & Senate: SpaceViews. Mars losses may mean end of 'faster - better - cheaper' strategy: AvNow. Comments from Gentry Lee: Space.com. String theory testable after all?New ideas emerging from theoretical workshops offer some hope of connecting the airy speculations about a Theory of Everything to reality: NYT.
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Sunspot count exceeds 300while the smoothed curve still hints at only a moderate maximum in the middle of the year - on a daily or weekly basis the sunspot number can fluctuate wildly, but when one averages the counts over a month they agree fairly well with the predictions: SpaceScience.Oversized ESO Press Release hails VLT resultsDoes having bigger telescopes imply that your press releases must grow accordingly? The latest from the European Southern Observatory concentrates just on some scientific findings from the UVES instrument at the Kueyen telescope - and still measures over 40 KB of text alone: Press Release.One shudders to think how big the press releases from the "OverWhelmingly Large Telescope" or OWL will be, a 100 meter diameter fully steerable telescope that ESO and other major observatories are now studying: OWL Concept Study plus Adaptive Optics for Extremely Large Telescopes. Chandra finds another X-ray bright galaxywith a veiled central engine - our census of active galactic nuclei might be far from complete: MSFC Release.How Chandra resolved the X-ray background (see Update # 167) is now described in Nature; coverage by Discovery. SeaLaunch flop traced to ground softwareA core team of Boeing experts is all but certain that the root cause of the failure of a Zenit rocket launched on March 12 is related to a ground software logic error: Boeing Press Release, Fla. Today, Space Daily, Space.com, Spaceflight Now, SpaceViews. Next SeaLauch attempt in summer: Fla. Today.
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Compiled and written by Daniel Fischer
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