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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| An experimental German companion. Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
Orbital, Space.com, Spacefl. Now, SpaceViews. The MTI satellite: Sandia infos # 3, 2, 1. SeaLaunch lift-off for first ICO satellite also on March 12: ICO, Space.com, BBC.
| (Lead rewritten March 10th as the original source, an NSF Press Release, was flawed) |
SOHO "sees through the Sun" with novel techniqueA week's warning of potential bad weather in space is now possible thanks to a new use of ESA's Solar and Heliospheric Observatory (SOHO) spacecraft: It has become possible to image activity regions on the far side of the Sun, using its Michelson Doppler Imager (MDI)! The method is called "helioseismic holography" and based on acoustic waves travelling throughout the Sun. The development of holographic seismic imaging was initially prompted by the discovery a decade ago that sunspots absorb and scatter incident acoustic waves: That makes it possible to use the almost classical technique of helioseismology, where the sound waves map the interior of the Sun, to see what's on the back side.Waves in the 2.5 to 4.5 mHz frequency range undergo a specular reflection at the solar surface, penetrating back into the interior where they are eventually refracted back to the surface thousands of km further from the source. 'Multiple-skip holography' based on this phenomenon thus facilitates imaging of active regions with "pupils" (thats the wave pattern MDI sees on the solar surface) far extended from the "focal point" (the source to be imaged). Indeed, it is even possible to extend the pupil of a holographic computation from the focal point to the opposite side of the Sun. Sunspot groups reveal themselves because there the Sun's surface is depressed slightly, and their very strong magnetic fields speed up the sound waves somewhat. As a result the sound waves arrive at the front side about 6 seconds earlier than equivalent waves from sunspot-free regions, in a total travel time of about 3 hours. The change in speed becomes evident when sound waves shuttling back and forth get out of step with one another - and this allows a crude plotting of the back side of the Sun! MDI data for 28-29 March 1998, in a first application of the method, revealed a sunspot group there that was not plainly visible on the near side until ten days later. MDI observations for 24 hours were more than sufficient to detect the hidden sunspots, which means that routine monitoring is a realistic possibility: Major active regions could be anticipated a week before they arrive on the near side.
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NASA considers launch to Pluto already in 2003!It seems that NASA wants to switch the first two outer planets missions of the next generation of spacecraft and to launch a fly-by probe to Pluto before the much talked-about Europa Orbiter sets sail: On the Outer Planets Announcement page of NASA's Langley Research Center, a March 1 entry asks "Pluto proposers" to "assess the impact of delivering their instrumentation early to support a Pluto launch in 2003." The hardware would have to be delivered by December 26, 2000, to meet a launch window in November 2003 - which would likely push the Europa Orbiter to 2004. Originally the Pluto-Kuiper Express launch was planned for December 2004.Project insiders think that "this move makes all kinds of sense. The Europa probe requires more advanced technology (which is probably the reason for the switch)," an internal circular from the 'Europa Icepick Group' says. A Pluto launch in 2003 would also be "far better, since Pluto is closer to the Sun - it allows the probe's trip to Pluto to be shortened by as much as 6 months (or, alternatively, the probe's weight can be raised from 150 kg all the way up to 200 kg) without changing the Delta 3 launch vehicle." There would also be a close Jupiter fly-by with a unique Io near-IR observation opportunity.
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ESA short-lists flexi missions, including exotic physics experimentsSix proposals, ranging from a visit to the asteroid belt to amazingly sensitive gyroscopes, will undergo close examination during the next six months, as the European Space Agency's science advisors move towards the selection of two so-called Flexi-missions for launch between 2005 and 2009, each cost-capped at 176 Mio. Euro. Science working groups and the Space Science Advisory Committee have chosen them from 49 ideas submitted after a call for proposals last October.The front-runner in the astronomy field is European participation with NASA in the Next Generation Space Telescope - although a formal decision will not be taken until later this year, much European effort has already gone into preparing for this NGST project, due for launch in 2008. That intensifies the competition for the other slot - here are the candidates:
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NASA confirms Galileo's "Millennium Mission"It's finally official: NASA plans to renew the solar system passport of the Galileo spacecraft by extending the mission exploring Jupiter and its moons through the end of 2000, when Galileo may embark on a joint scientific expedition with the Saturn-bound Cassini spacecraft. During this new extension, called the Galileo Millennium Mission, tour planners hope to include three high-priority scientific observations in 2000. First, Galileo will perform two additional flybys of Jupiter's moon Ganymede, the largest moon in the solar system, on May 20 and December 28. Scientists hope these flybys - with the highest resolution pictures ever taken of this icy world - will tell us more about Ganymede's geologic history.And then Galileo would team with Cassini for simultaneous observations of the Jupiter system and its magnetic environment from two vantage points when Cassini visits Jupiter's neighborhood in December 2000 - Jupiter's powerful gravity will be used to "slingshot" Cassini toward Saturn. One spacecraft will be inside Jupiter's magnetic envelope, with the other outside where it can observe the powerful solar wind pressing on the envelope. From the two positions cause and effect as the wind changes the magnetic properties around Jupiter can be studied two highly capable spacecraft at the same time - a real bonus for both missions. Galileo's mission planners are already exploring various options for the mission's eventual conclusion, including possible further encounters with Io and another Jovian moon, Callisto. Planners are looking into a possible impact with Io or Jupiter for a mission finale, with other options are also being considered. They are trying to avoid an impact with Europa because recent evidence suggests there may be a liquid ocean beneath its icy crust, raising the possibility that life could exist there. |
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Observational discovery of cosmic astigmatism caused by Dark Matter in the UniverseAn international team based in France has announced the first direct detection of Dark Matter in the Universe by measuring the "cosmic astigmatism" caused by gravitational lensing: Using a series of deep images obtained at the Canada-France-Hawaii Telescope, they analyzed the shapes of some 200 000 faint galaxies spread over two square degrees of the sky - and the galaxies appear to be elongated in a coherent manner over large regions of the sky. The measured effect is small, a percent or so deviation from a purely random distribution of shapes, but the accuracy of the results leaves no doubt that the signal is due to the gravitational lensing effect of the Dark Matter distribution.These results have been partially confirmed by subsequent reports from two teams, one English and the other American, who have studied different patches of the sky - see Update # 165 (story 4) for similar work on data from the Sloan Digital Sky Survey. The measurement of cosmic astigmatism has been the object of a lively international competition: The predicted signal is so weak that the prospects of a successful detection seemed very poor, but the importance of the measurement was too great to simply abandon the effort. In order to mount a comprehensive attack on the problem, the research team assembled by the IAP had put in place a multi-year program to fully exploit the new wide-field CCD camera at CFHT. |
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Does Al Gore remember ...?The presidential hopefuls haven't said much about space policy matters during the primaries (as also noted by SpaceViews and Space.com), and Al Gore's current views are "less enthusiastic about human missions in the solar system." But guess what the 2000 Democratic presidential nominee Gore said 12 years ago during the 1988 primaries: If he would be elected president, the then-39 year old had boldly declared, he would take money away from the Pentagon, give it to NASA and then organize an international manned mission to Mars... (AW&ST of Feb. 1, 1988, p. 15)"GoreSat" Triana has a scientific valueSo says the National Research Council that calls the $70 million satellite "a small mission that explores a new Earth observing perspective and provides unique data" - now Triana, watching Earth from L1, may fly after all: Homepage, Scripps Press Release, Space.com, NYT, Fla. Today, Aviation Now, SpaceViews.X-33 program "on the verge of failure" due to a significant design-related problem with the suborbital vehicle's two lightweight fuel tanks: Fla. Today. NASA wants ideas for its Future Space Transportation plan - the aim is (again) a 2nd-generation reusable launch vehicle (RLV) system, to be chosen in 2005 and operational in 2010: MSFC Press Release. Is Boeing's AirLaunch a good idea? It could change the whole dynamic of the way satellite users operate: Fla. Today. Dwarf galaxies can cook their own moleculesRadio observations have provided new insights into how galaxies recycle themselves, losing matter in 'tidal tails' after interactions, in which new small galaxies condense - and those, the new observations of carbon monoxide show, can cook their gases into the molecular material needed to make new stars: Nature Science Update, Space.com."Mission to Mars" movie "unpalatable"?"Mission to Mars" (starting U.S.-wide on March 10th) "takes some of humanity's most profound intellectual challenges, interplanetary exploration, the origin of life, extraterrestrial intelligence, and runs them through the Hollywood meat-grinder - the result is unpalatable, to say the least," complains Space.com about the latest SF flick (which, the producers brag, had heavy tech support from NASA, esp. astronaut Story Musgrave).According to CNN "Mission to Mars" even "takes bad to a whole new level." And SpaceRef calls it "yet another failed Mars mission" - one more bad film about man on Mars, then? Here is more from the IMDB, where early reviewers are split, but most call it "terrible", "a very very bad movie", even "the worst movie I've seen in years". Fla. Today discovered "thought-provoking entertainment," though, and the AP calls the movie "practically an advertisement for human space travel"... NASA at the Martian crossroads - the options of the Mars Surveyor program for the next decade are slowly getting clearer: Space.com. Internal discussions on NASA's Mars program prolonged - no big announcement will come in mid-March: Space.com, SpaceViews.
MGS MOC shows differences between the Martian polesThe North polar cap has a relatively flat, pitted surface that resembles cottage cheese, while the South polar cap has larger pits, trough and flat mesas that give it a holey, Swiss cheese appearance: JPL Press Release, NSU, SpaceScience, MSSS overview (click on the 10 thumbnails!), SpaceRef, Spaceflight Now, Space.com, SpaceViews, BBC, Discovery, CNN, SPIEGEL.MGS TES surveys Mars' mineral composition and delivers a detailed map showing mineral abundance - the surface materials are primarily volcanic, as expected: ASU Press Release. New topographic shade maps of Mars have been produced from the MGS MOLA data: the maps (including spectacular hi-res versions), MOLA Homepage, SpaceRef. MGS MOC revisits site seen by Mariner 7, a feature that at the time was nicknamed "the Giant's Footprint": MSSS, Space.com, Spacefl. Now. |
Iridium about to fall - and the 66 satellites, too!With no savior in sight, the end of the Iridium company seems to be imminent, with a final deadline of March 17 approaching - and majority shareholder Motorola plans to send all the 66 satellites into the atmosphere in a controlled fashion over the next few years: Space.com, Space Daily, Fla. Today.The case for a giant radio telescopecalled Square Kilometer Array (SKA) has been made once more at a meeting in Puerto Rico - where it was also evident that the project is pretty far from even making basic decisions, let alone secure funding: Cornell Press Release, SKA International Homepage, U.S. SKA consortium.Meanwhile astronomers vow to save the "12 meter" radio telescope on Kitt Peak that faces closure this summer (see Update # 177 small items as well as Nature of March 2 p.7 and Science of March 3 p. 1573-5): The Cosmic Mirror has seen several e-mailed calls for action. The more sober ones point out that the U.S. stands to lose much expertise in the 5-year interval before ALMA is on, while an anonymous radical sees a big conspiracy at work... Antenna damaged - and repaired - on AtlantisThe Ku-band antenna of the next orbiter to fly, a graphite-epoxy dish about 90 cm in diameter, had struck a "bridge bucket", a cherry picker-like device stationed above the cargo bay, as it was being retracted into a stowed position on March 5 - it has since been repaired with epoxy resin, and no launch delay is expected: Status of March 8. Earlier worries: Space.com, AP, CNN, Spaceflight Now, Fla. Today, SpaceViews.No paying Mir visitors in sightNot a single tourist is yet to begin training for a commercial flight to the Mir space station: Space Daily. First MirCorp customers to be announced soon? AvNow. Mir IPO next year: Space.com.ISS chief engineer happy after visit to Proton plant"Adequate and appropriate corrective action has been implemented" to make the Russian Proton reliable again, he reported after visiting the engine plant - the rocket that must carry the Zvezda module to the ISS: NASA Watch, SpaceViews.Hubble surveys 27 Planetary Nebulae in the LMCand finds that bipolar nebulae are richer in some heavier elements, such as neon, than those with a more spherical shape - a higher abundance of neon in "bipolar" planetary nebulae indicates that the stars that sculpted these objects were born more recently: STScI, BBC, CNN, SPIEGEL.Do we have to be afraid of Eta Carinaeexploding in our neighborhood, perhaps as a hypernova? Eta Carinae (which started to brighten recently; see Update # 133) could blow anytime, or it could continue rumbling and spewing gas for thousands of years: Space.com = EZ.Recent visual estimates for Eta Car scatter around 5.0 magnitudes: AAVSO Quicklook - scroll down to "1041-59". But the overall lightcurve shows a clear trend up: Enter "Eta Car" into the Light Curve Generator!
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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
