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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion - only available here! Current mission news: MGS (latest pictures!) + Cassini + Stardust |
Most saw just a brilliant flash of light when - most likely - a bolide exploded early on Jan. 21: NZ, CENAP. The last Euro-bolide shocker of Jan. 4 (see last Update header): detailled SPMN News. A first meteorite from that bolide? El Mundo. Earlier: CENAP. And a stellar occultation by Mars on Jan. 14 has been documented by Gaehrken.
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HRSC delivers from Mars Express, APXS & MIMOS deliver from Spirit: Mars now fully under German controlBy a strange turn of events, German planetary scientists are now in charge of the most important scientific studies taking place both in orbit around and on the surface of Mars: The High Resolution Stereo Camera (HRSC) on ESA's Mars Express, built in Berlin, has started taking hi-res 3D images of the surface that have never been possible before - and the two chemistry instruments on Spirit's robotic arm, APXS and MIMOS II, that have studied Martian soil and are now in touch with the first rock, were both built in Mainz. The German national space budget may be minuscule compared to others, but in certain areas decades of experience are paying off - and the space agencies are turning to big and even small research institutes here for the most advanced sensor systems to be taken to other planets. |
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On Jan. 19 the first HRSC image was published, as a teaser for more to be presented on
Jan. 23. Although the seven scientific instruments on board Mars Express are still
undergoing a thorough calibration phase, they have already started collecting amazing
results. The first spectacular stereoscopic color picture was taken on Jan. 14 from 275
km above the surface of Mars: It shows a portion of a 1700 km long and 65 km wide swath
which was taken in south-north direction across the Valles Marineris. It is the first image
of this size that shows the surface of Mars in high resolution (12 meters per pixel), in
color, and in 3D. The latter is made possible because the instrument scans the ground not
only in the nadir but also a bit ahead and behind on the track. Meanwhile Spirit has driven 1.9 meters to its first rock, Adirondack, and is already measuring its composition with the Alpha Particle X-ray Spectrometer and the Moessbauer Spectrometer MIMOS II as well as studying its detailled structure with the Microscopic Imager. Earlier the two chemistry instruments had been pointed to the soil in front of the rover: One unexpected finding there was the MIMOS' detection of a mineral called olivine, which does not survive weathering well. This spectrometer identifies different types of iron-containing minerals; scientists believe many of the minerals on Mars contain iron. The lack of weathering suggested by the presence of olivine might be evidence that the soil particles are finely ground volcanic material; another possible explanation is that the soil layer where the measurements were taken is extremely thin, and the olivine is actually in a rock under the soil. Opportunity corrects trajectory, Spirit studies Martian soil - and the first Mars Express images "blow away" ESA scientistsWith barely a week before reaching Mars, Opportunity has adjusted its trajectory, or flight path, on Jan. 16 for the first time in four months. The maneuver began with a 20-second burn in the direction of the axis of rotation, then included two 5-second pulses perpendicular to that axis. Before the thruster firings, Opportunity was headed for a landing about 384 km west and south of the intended landing site Meridiani Planum, on Jan. 25 at 5:05 UTC - the maneuver was designed to put it on course for the target. Opportunity's schedule still includes two more possible trajectory correction maneuvers, on Jan. 22 and Jan. 24, but the maneuvers will only be commanded if needed.Meanwhile the Spirit rover reached out with its versatile robotic arm on Jan. 16 and examined a patch of fine-grained martian soil with a microscope at its end. The microscope can show features as small as the width of a human hair. While analysis of the images from the instrument has barely begun, the first impression is that some of the tiny particles appear to be stuck together. Before driving to a selected rock early next week, Spirit will rotate the turret of tools to use two spectrometer instruments this weekend on the same patch of soil examined by the microsope: The M�ssbauer Spectrometer identifies types of iron-bearing minerals, and the Alpha Particle X-ray Spectrometer identifies the elements in rocks and soils. And in orbit, 6 of the 7 instruments on Mars Express have already been turned on and are delivering already impressive test data - the German High Resolution Stereo Camera in particular is said to "blow away" mission scientists with its three-dimensional views. However, the public will see the first results on January 20 the earliest (this delay has promptly been criticized by the German chapter of the Mars Society). The 7th and potentially most important instrument, a ground penetrating radar, will only be activated in spring. Meanwhile the main engine of the orbiter has been sealed after its last use on Jan. 11, and the final orbit corrections will be performed with small thrusters only: It should be reached by Jan. 28 and measure 260 x 11,500 km.
With the help of existing orbiter views, the general travel route for the next weeks has been decided nonetheless - and when ESA's Mars Express flies over the area on Jan. 16 in a particularly low and rare approach, it will point down its instruments as well in a coordinated effort (while Spirit is looking up): Especially the IR spectra from the OMEGA instrument and the 10 m/pixel views from the HRSC should help Spirit's drivers find the most promising regions. The first target will be a 200 meter impact crater some 250 meters away: Spirit will look at the ejecta blanket and perhaps even climb the crater rim. And then it's off to the »eastern hills«: At some 3 km distance, the rover may never reach them, but it will at least get clearer views of these fascinating mountains, up to 100 m high. |
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Astronomers vow to fight for the survival of HubbleThe questionable decision by NASA to cancel all HST Servicing Missions has led to great outrage in the astronomy community worldwide - and the first action plans on all levels, from the purely technical (how can we exted the scientific life of the satellite?) to the political (which leading politicians should we approach with what arguments?). Here is a statement from Steve Beckwith, director of the Space Telescope Science Institute: "We have had an outpouring of sympathy from friends around the world, including many in the general public. I want to thank all of you for your support during this difficult time and tell you that I appreciate your ideas to preserve the great science we plan for the future.We are setting up several tiger teams that will include Institute and NASA members to look at the different options for Hubble's future. I will create a web link from our main page allowing you to submit your own ideas and follow our progress as we grapple with the challenges posed by the SM4 cancellation. Although I believe we have the best minds in the world right here to address these challenges, we will all profit by getting the widest suite of ideas from people in academia, industry, and the public at large." There is even talk about asking Russia for help in an improvised SM! Meanwhile the ST-ECF, STScI's European counterpart, says in a statement: "There is little we Europeans can do directly to change NASA's decision which, apparently, is final. We believe strongly, however, that it should be made known how universal the feeling of disappointment is within the scientific community." First victim of the "vision": NASA cancels Servicing Mission 4, dooms Hubble Space TelescopeThe Cosmic Mirror's worries about the impact of the new lunar craze on NASA's space science program outlined below have proven justified just one (!) day later: O'Keefe has abruptly cancelled the next Servicing Mission to the HST which was just recently delayed to 2006 but nonetheless considered essential for the continued use of the space telescope until about 2010. Now the latter will age in orbit and probably fail by 2008 - and two newest-generation scientific instruments already under contruction will never be installed (although they could fly, in principle, on small extra satellites). The cancellation of SM4 was justified by the expenses needed to develop autonomous TPS repair techniques for this only non-ISS-bound mission - this had not been an argument before, however, and there is slim hope that the decision will be overturned by Congress (a letter-writing campaign was launched by STScI scientists only hours after the news broke) ...Meanwhile overall cost estimates for the manned lunar program until 2020 (i.e. even without any Mars etc. missions launched from there) are emerging, and they are stunning: They range between 120 and 170 billion dollars, and a high-ranking ESA manager has confirmed that NASA gave him a figure of 130 billion dollars. Historically the first cost estimates for major space ventures have always been way to low (remember that the space station should have cost $8 billion once, to completion?) - thus one might assume that the whole project could easily cost half a trillion dollars and still not lead to humans on Mars. That is if it doesn't collapse way before 2020 - the parallels to the ill-fated "Space Exploration Initiative" of 1989 are evident. NASA itself will change in any case, though, and a major internal restructuring is already under way.
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Superrelativistic jet of neutron star source shows that black holes aren't the only explanationRadio astronomers have found a neutron star spitting out a jet of matter at very close to the speed of light: This is the first time such a fast jet has been seen from anything other than a cosmic source generally assumed to be a black hole. The discovery challenges the idea that only black holes can create the conditions needed to accelerate jets of particles to extreme speeds. The scientists, from The Netherlands, the UK and Australia, studied Circinus X-1, a bright and variable source of cosmic X-rays, over a three-year period. Circinus X-1 lies inside our Galaxy, about 20,000 light-years from Earth in the constellation Circinus near the Southern Cross. It consists of two stars: a 'regular' star, probably about 3 to 5 times the mass of our Sun, and a small compact companion.It is certain that the companion is a neutron star from the kind of X-ray bursts it's been seen to give off: Those X-ray bursts are a sign of a star that has a surface. A black hole doesn't have a surface - so the companion must be a neutron star. The two stars in Circinus X-1 interact, with the neutron star's gravity pulling matter off the larger star onto the neutron star's surface. This `accretion' process generates X-rays. The strength of the X-ray emission varies with time, showing that the two stars of Circinus X-1 travel around each other in a very elongated orbit with a 17 day period - at their point of closest approach, the two stars are almost touching. Since the 1970s astronomers have known that Circinus X-1 produces radio waves as well as X-rays. A large `nebula' of radio emission lies around the X-ray source, and within the nebula lies the new-found jet of radio-emitting material. Jets are believed to emerge, not from black holes themselves, but from their 'accretion disk' - the belt of dismembered stars and gas that a black hole drags in towards it. In Circinus X-1 it's likely that the accretion disk varies with the 17-day cycle, being at its most intense when the stars are at their closest point in the orbit. The jet from Circinus X-1 is travelling at 99.8% of the speed of light. This is the fastest outflow seen from any object in our Galaxy, and matches that of the fastest jets being shot out of other complete galaxies. In those galaxies, the jets are generally (though not universally) thought to come from supermassive black holes, millions or billions of times the mass of the Sun, that lie at the centres of the galaxies. Whatever process accelerates jets to near the speed of light, it does not rely on the special properties of a black hole. |
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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
