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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 |
Or rather the World Year of Physics: international, German and American homepages, the Quantum Diaries (where physicists say what they're doing right now), the Einstein@Home project, an Einstein portal by the MPI f�r Gravitationsphysik, a demonstration by the MPIfR and coverage on Feb. 7: BdW. Feb. 2: NZ. Jan. 20: ZEIT. Jan. 19: AP, NZ (andere Story).
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Ariane 5 Heavy shows its mettle in 2nd tryThe first launch had quickly turned into one of the darkest days for European space technology: Soon after the Ariane-5 ECA had cleared its launch pad on Dec. 11, 2002, the nozzle of the first stage engine overheated and fell apart, and the rocket had to be destroyed in minutes (see Updates # 246 story 4 and 247 lead). The recovery took 26 months - in which the older Ariane-5 version continued to fly occasionally - and was worth the effort: On February 12, 2005, a much improved version carried a real telecom satellite, a small experimental satellite and an instrument-laden dummy satellite into the correct geostationary transfer orbit. After another test flight in the middle of the year, the ECA is now poised to become the new workhorse of Arianespace, capable of launching two modern heavy comsats at the same time: This was the strategy that once led the Ariane 4 to commercial success with double launches of the smaller comsats of decades past.The payload on the crucial test flight - Ariane's 164th in total - was sharing the double launch adaptor Sylda: on top sat the real satellite XTAR-EUR, on the bottom the dummy satellite Maqsat- B2 which provided a dead mass of 3.5 metric tons, collected data from some 60 sensors and carried the tiny SloshSat-FLEVO (which will do fluid physics experiments important for satellite fuel tanks for some 10 days) and a video camera. While SloshSat was deployed, Maqsat itself stayed connected to Ariane's upper stage, in order to minimize space debris. The Ariane-5 ECA differs from the regular version - now soon to be phased out - in having a stronger first stage with more fuel and a new cryogenic engine (the one with the nozzle that had failed so miserably in 2002), stronger solid rocket boosters and also a new cryogenic upper stage with a motor already used in the 3rd stage of the Ariane-4. Alltogether this yields so much capacity that almost all combinations of two heavy satellites can be handled in one launch. |
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The first Milky Way star with more than escape velocityhas been discovered: It is twice as fast as needed to leave the gravitational field of the Galaxy forever, and it will exit 80 to 100 million years from now. The star was probably part of a binary system that formed in the vicinity of the Galactic Center (that's indicated by its high metallicity) and which later came very close to the compact central mass (and possible supermassive black hole) Sgr A*: The pair was ripped apart by its gravity, with one star remaining there while the other star was kicked out with extremely high speed. This star is now travelling with some 710 km/s away from the Galactic center, with the motion vector pointing straight away from it. This strongly supports the acceleration scenario for this particular case - which had been suggested theoretically some time ago. But discovering stars that actually suffered that fate is a tedious job, and it is no wonder that the first case was found in the data base of the Sloan Digital Sky Survey, though the key measurements were later made with another telescope. |
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Another - modest - budget increase requested for NASA, with no funds at all for a final HST servicingIt is certainly not the last word regarding the fate of the Hubble Space Telescope - which will be more or less sealed this year, perhaps as early as spring - but it's what the White House and the current NASA leadership have in mind: Only 93 million dollars are foreseen in the FY 2006 budget request, including $75m for work on a robotic satellite to destroy the orbiting observatory after its key systems fail in a few years. Gone is the vision of a supercomplex servicing robot that would replace the aging components, install new scientific instruments and send the satellite to the fishes only after many more productive years. And no provision whatsoever for a reinstallment of the previously planned shuttle servicing mission is made either. Ironically these developments are justfied by NASA by accepting one half of the judgement by the independent Committee on the Assessment of Options for Extending the Life of the Hubble Space Telescope (see Update # 284 green box) - while at the same time ignoring the other half of its final report from last December!That study had severely questioned the wisdom of sending a complex, unproven robot - developped in little time - to the HST and had seen a high risk of failure: a view which in turn was questioned by many NASA engineers who feel they would be up to the task. And who had heard numerous times last year that the NASA management was behind them and was even viewing their servicing robot as an important investment in the future. On the other hand the Committee had argued that a manned servicing mission was hardly any more dangerous than a flight to the ISS and that thusly the original plans for a shuttle servicing mission (»SM 4«) should continue. In its wisdom NASA now abruptly agrees that the servicing robot in untenable - but at the same time the advice w.r.t. the benefits of manned servicing flight is flatly dismissed. There will be considerable political fighting over Hubble's fate in the coming weeks - which will also see the departure of the satellite's nemesis, the current NASA administrator, on February 21 - as the HST has as much political support as ever in the U.S. Congress and the population at large. So what is contained in the requested $16.45 billion FY 2006 budget? In a nutshell, it provides some $3.2b for the so-called Exploration Systems, including $750m for the crew exploration vehicle, which will carry astronauts to the moon in the next decade, $800m for research and technology to ensure the health, habitation, safety and effectiveness of future astronauts and $920m for investments in the technologies and capabilities that will make an ambitious and sustainable 21st-Century space exploration program possible. There is also $320m for a redirected space nuclear program (not going to Jupiter in the first mission anymore but to a different destination TBD), intended to further open the space frontier by providing large amounts of electric power for activities that cannot use solar power. There are also approximately $1.9b for the Space Station program, $4.5b for the Space Shuttle program and $4.2b for NASA's programs to explore the solar system and universe and to research the Sun and its impact on Earth and the space environment. |
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"Missing baryons" all found: as clouds in intergalactic spaceAnother major success of the current - i.e. since 1998 - standard cosmology: Astronomers are finally tracking down the whereabouts of most of the baryonic ('normal') matter that was created in the Big Bang but doesn't show up as stars or gas in the galaxies. The Chandra X-ray Observatory has discovered two huge intergalactic clouds of diffuse hot gas: The are the best evidence yet that a vast cosmic web of hot gas contains the long-sought missing matter - about half of the atoms and ions in the Universe. Computer simulations of the formation of galaxies and galaxy clusters had indicated for some time that the missing baryons might be contained in an extremely diffuse web-like system of gas clouds from which galaxies and clusters of galaxies formed.These clouds have defied detection because of their predicted temperature range of a few hundred thousand to a million degrees Celsius, and their extremely low density. Evidence for this warm-hot intergalactic matter (WHIM) had been detected around our Galaxy, or in the Local Group of galaxies, but the lack of definitive evidence for WHIM outside our immediate cosmic neighborhood made any estimates of the universal mass-density of baryons unreliable. The discovery of much more distant clouds came when Chandra took advantage of the historic X-ray brightening of the quasar-like galaxy Mkn 421 that began in October of 2002. Two Chandra observations of Mkn 421 in October 2002 and July 2003, yielded excellent quality X-ray spectral data. These data showed that two separate clouds of hot gas at distances from Earth of 150 and 370 million light years were absorbing X-rays from Mkn 421. The X-ray data show that ions of carbon, nitrogen, oxygen, and neon are present, and that the temperatures of the clouds are about 1 million degrees Celsius. Combining these data with observations at ultraviolet wavelengths made it possible to estimate the thickness (about 2 million light years) and mass density of the clouds. Assuming these clouds to be representative, the first reliable estimate of average mass density of baryons in such clouds throughout the Universe was then possible: It is consistent with the mass density of the missing baryons. |
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Wind speeds on Titan deduced from Huygens radio trackingRadio astronomers have been able to get a first profile of the wind speeds on Titan from the tracking of the Huygens probe's feeble carrier by the Green Bank Telescope: The Doppler effect on the signal's frequency tells them that at 50 km altitude there is a zonal, prograde wind of 40 to 50 meters per second, with the speed decreasing to just a few meters per second near the ground. In the upper atmosphere, however, really weird things are going on, with dramatic jumps in the Doppler signature around the time when the third and final parachute had been deployed - this must have been the most demanding time of the descent, and yet Huygens came through with flying colors. It is now also known that Cassini recorded Huygens' data stream for exactly 3 hours, 40 minutes and 3 seconds, including 1 hour, 12 minutes and 13 seconds from the ground. (Talk by Mike Bird at the Univ. of Bonn on January 25)Ample - but indirect - evidence for liquid methane on TitanThat is the quintessence of one week of analysis of the data from the European Huygens probe that descended through the atmosphere of Saturn's biggest moon and made it all the way to the surface (see last Update lead), as presented at a news conference by key researchers at the headquarters of the European Space Agency in Paris on January 21st. Huygens had woken up at 4:41 UTC spacecraft event time one week earlier, hit the upper atmosphere at 9:06 and the ground at 11:38. And then Cassini could receive its continuing data stream for another whopping 72 minutes, while radio telescopes on Earth saw it even longer (when Huygens actually died is still not known, but radio telescopes in Germany or the Netherlands should have caught its last transmissions). The Huygens scientists have now dug deeper into the data trove - and convinced themselves that a liquid, namely methane, does exist on Titan's surface, though only intermittently and not in the location and at the time where & when Huygens arrived.Thanks to stereoscopic analysis - the same features were imaged repeatedly during the descent, from varying altitude - Marty Tomasko of the DISR instrument now knows that the bright regions are hills, about 100 meters above the dark plains: This strengthens his initial guess that the dark, dendritic features on the hills are drainage channels. These channels appear so dark because material with an albedo of only 12% has gathered on their floors, apparently the same stuff making up the dark plains which have an albedo of 10%. A big picture is emerging here: It rains dark organic stuff from the atmosphere onto the hills, which consist of somewhat dirty water ice. Occasional methane rain washes the dark stuff off the icy hills, it is transported down to the plains in the drainage channels, and it eventually settles in the plains where the methane then drains away. Many features seen in the DISR images support this view, e.g. teardrop-shaped mounds, and numerous elliptical features are apparently the remains of the last pools where liquid methane had been standing. No one knows when it has rained the last time on Titan, perhaps it happens daily, perhaps only once in a while in a 'rainy season'. And it is also not clear how typical the region investigated by Huygens is for Titan as a whole. But the conclusions from the DISR images match nicely with the data from the other instruments (those of the aerosol detector haven't been analyzed yet but seem to be good). So there you have it: Titan is the one world in the solar system that most closely resembles Earth - but with vastly different consituents and at a drastically lower temperature. The role of Earth's silicates is played by dirty water ice, methane stands in for water and organic components that form in the upper atmosphere play the role of dirt on Earth. There is weather and a 'hydrological' cycle (for lack of a better word) - and there are dreams of returning to this amazing world. At the press conference Huygens chief scientist Jean-Paul Lebreton was already proposing a kind of Mongolfiere to hover over the surface, and the latter would also support a MER-style rover. Until it rains the next time, that is ... |
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Mars UpdateMars Express is finally cleared to deploy the MARSIS antennae in early May, has spotted a nightglow in Mars' upper atmosphere and possibly a frozen lake - and ESA's damning report of the Beagle 2 failure is finally out in the open! The Report (PDF, 42 pg.), Alenia Spazio [SR] and BNSC Releases, ESA Releases of Feb. 8 and Jan. 28 and coverage of Feb. 15: Mars Society of Germany Story. Feb. 9: AB. Feb. 8: BBC, Nat., ST. Feb. 4: Times, ST. Feb. 3: BBC, PA, UPI, New Sci. Jan. 31: PSRD, AB. Jan. 28: RFN. |
The meteorite discovery by MER Opportunity is now confirmed, while
Spirit's "Peace" discovery causes excitement. MER Press Releases of
Feb. 15 and
Jan. 19,
pictures #
73
27,
21,
72
69,
a raw image and
another one, a
color version, a
collection of images, various
microscopic imager
views of the meteorite and coverage of
Feb. 15:
Dsc.,
FT.
Feb. 1:
AB.
Jan. 25:
SC.
Jan. 24:
AB.
Jan. 21:
Plan. Soc.
Jan. 20:
S&T,
BBC,
Cornell Daily Sun,
SC.
Jan. 19:
SC.
Jan. 18:
New Sci.,
NZ.
Jan. 17:
SC.
MGS spots the MER and their tracks: Opportunity [SR] between Eagle & Endurance and Spirit in Gusev - and the 1000th captioned MOC image release. Meet the MRO: AW&ST (long!). MSL instruments: Cornell Sun. |
Swift images its first Gamma Ray BurstThe bright and long burst occurred on January 17 and was in the midst of exploding, as Swift autonomously turned to focus in less than 200 seconds - the satellite was fast enough to capture an image of the event with its XRT while gamma rays were still being detected with the BAT: NASA Release. The UVOT is also operational: PSU PR [SN]. And the first afterglow observations of Swift-discovered bursts take place: Carnegie Inst. PR [SR].KORONAS-F solar satellite delivers data that make it possible to re-create the three-dimensional structure of the solar corona: Novosti. New Tatyana satellite - launched Jan. 20 - observes solar flare (the one mentioned in the right column): Novosti. Deep Impact s/c imagedon Jan. 13 with the Palomar Obs. 5 m telescope: PhotoJournal. And a picture of the target comet on Jan. 15 by M�ller; see also the D.I. amateur observers homepage and the STSP program. DI's �processor: Press Release. Coverage of Feb. 5: M.W.DailyN. Jan. 26: DiamondBack. Jan. 20: Cornell Chr.First Genesis early-science sample sent to researchers - the shipment marked the first distribution of a Genesis scientific sample from JSC since the science canister arrived on Oct. 4, 2004: NASA Release [SN].
Fastest X-ray pulsar foundIt spins at a record speed of 600 revolutions a second, feeding off a nearby companion star to maintain its energy: AFP, ORF.The biggest stars produce the strongest magnets when they die - the result is a magnetar: CfA and CSIRO Press Releases, SC.
Brown Dwarf masses underestimated?These failed stars may be twice as heavy as predicted - this means that some objects previously identified as "free-floating" exoplanets may in fact be much heavier and thus could be considered brown dwarfs instead: U of A, ESO and MPG Press Releases, S&T, SC, ST, BdW. Warm gas around BD: PSU Release.A dust disk around a small Brown Dwarf may be able to form planets: a paper by Luhman & al., Spitzer, CfA and JPL Releases, PhotoJournal PIA073 37, 36 and 35 and coverage by BBC, New Sci. "Pulsar comet" now officialWhat the Cosmic Mirror revealed over two years ago in Update # 244 has now been described at a media telecon (where also the hypothesis of carbon planets was discussed) by the discoverer: PSU and Kuchner Press Releases, S&T, BBC, Dsc.Pluto's Charon may have formed in a giant collision, just like our Moon: SwRI Press Release, ST. |
IBEX selected as next Small Explorerby NASA, will make the first map of the boundary between the Solar System and interstellar space - and the NuSTAR satellite project with an imaging hi-energy X-ray telescope will also be studied further: NASA, SwRI, Caltech and Orbital Releases, Chic. Trib., SC Sent., ST.SMART-1 approaching final lunar orbitThe ESA orbiter has captured its first close-range images of the Moon in January - and the mission has been extended until Aug. 2006: ESA Releases and Status of Feb. 15, Jan. 26 and Jan. 17, BBC, Nature, NewS, BdW, NZ.NASA selects Moon Mapper for Mission of Opportunity for Indian moon probe - the final confirmation subject to negotiations between NASA and ISRO: NASA Release [PR]. Major sunspot group crossed the diskin mid-January - it also produced several big flares and on Jan. 20 the strongest proton storm in 15 years; it was still big on the far side but has since decayed: Jan. 30 far side view, NOAA Report (earlier, still earlier), Advisory Bulletin (earlier, still earlier), NOAA Press Release, Science@NASA, Jan. 16 SOHO, Karrer and Koeman pictures and coverage by ARRL, New Sci., AFP, SC, ST and NZ. Plus a cool prominence on Feb. 6 as imaged by Karrer and Seidenfaden.Machholz still displaying a nice tail, while the coma fades: image collections by Mrozek & Skorupa (!) and G�hrken, collected reports by Vollmann and more pictures of Feb. 6: M&S, Feb. 5: G�hrken, M&S, Feb. 4: Holloway. Jan. 31: Basili. Jan. 30: J�ger & Rhemann. Jan. 27: Holloway [alt]. Jan. 21: Holloway. Jan. 18: Koprolin (color animation!), Jan. 16: Holloway, G�hrken (hi-res, w/jets), James (more jets), Sostero (other processing). Jan. 15: Skorupa, Mrozek. Jan. 14: Karrer (next to California nebula), Hackmann. Where it is now: S&T. And SC with SF. The "2004 MN4 show" in 2029 gets better than expected - the NEO will rush by with 3rd mag. at 42°/hour: NEO News, S&T, SC. It could break up then: Ast. "The saga" of MN4: NEO News.
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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
