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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 |
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Currently under construction: a table of unusual and sometimes also spectacular celestial events (that can be predicted with some certainty); suggestions for further entries are welcome!
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Near-Earth Asteroid reaches highest scores to date on hazard scalesA recently rediscovered 400-meter Near-Earth Asteroid (NEA) is predicted to pass near the Earth on 13 April 2029 - the flyby distance is uncertain and an Earth impact cannot yet be ruled out. The odds of impact actually stand at 1.6 percent as of December 25, giving 2004 MN4 by far the hightest risk rating ever assigned to a minor planet: +1.02 on the Palermo and 4 on the Torino Scales. The brightness of 2004 MN4 suggests that its diameter is roughly 400 meters and our current, but very uncertain, best estimate of the flyby distance in 2029 is about twice the distance of the moon, or about 780,000 km. On average, an asteroid of this size would be expected to pass within 2 lunar distances of Earth every 5 years or so. Most of this object's orbit lies within the Earth's orbit, and it approaches the sun almost as close as the orbit of Venus. 2004 MN4's orbital period about the sun is 323 days, placing it within the Aten class of NEAs, which have an orbital period less than one year.2004 MN4 was discovered on 19 June 2004 by the NASA-funded University of Hawaii Asteroid Survey (UHAS), from Kitt Peak, Arizona, and observed over two nights. On 18 December, the object was rediscovered by the Siding Spring Survey, another NASA-funded NEA survey. Further observations from around the globe over the next several days made the connection to the June discovery, at which point the possibility of impact in 2029 was realized by the automatic SENTRY and NEODyS systems. At first the impact probability in 2029 was 1:300, but after 2004 MN4 was tracked very carefully by more astronomers around the world, on Dec. 24 the impact probability for 2029 has risen to about 1.6%, which for an object of this size corresponds to a rating of 4 on the ten-point Torino Scale. Nevertheless, the odds against impact are still high, about 60 to 1, meaning that there is a better than 98% chance that new data in the coming days, weeks, and months will rule out any possibility of impact in 2029. |
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GALEX survey turns up strange new class of nearby UV-bright galaxies, resemble those 10 Gyr agoIt's the first major discovery of the Galaxy Evolution Explorer satellite: a new class of rare but nearby galaxies with a high UV flux. In all aspects they resemble modern large galaxies (like ours) as they looked like 10 billion years ago - but the new galaxies are relatively close to us, ranging from two to four billion light-years away; they may be as young as 100 million to one billion years old. The discovery suggests our aging universe is still alive with youth. It also offers astronomers their first, close-up glimpse at what our galaxy probably looked like when it was in its infancy. Now we can study the ancestors to galaxies much like our Milky Way in much more detail than ever before: It's like finding a living fossil in your own backyard.The new discoveries are called ultraviolet luminous galaxies: They were discovered after the Galaxy Evolution Explorer scanned a large portion of the sky with its highly sensitive ultraviolet light detectors. Since young stars pack most of their light into ultraviolet wavelengths, young galaxies appear to the spacecraft like diamonds in a field of stones. Astronomers mined for these rare gems before, but missed them; since they weren't able examine a large enough slice of the sky. GALEX surveyed thousands of galaxies before finding these few dozen ultraviolet-bright ones. They are about 10 times as bright in ultraviolet wavelengths as the Milky Way, indicating that they are teeming with violent star-forming regions and exploding supernova, which are characteristics of youth. |
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Planets and dust disks seen around the same starsThe Spitzer Space Telescope has discovered for the first time dusty discs around mature, Sun-like stars known to have planets. The six stars average 4 billion years old, nearly the same age as the Sun. They are known to have gas planets (via their radial velocity effect), and rocky planets may also be present. Prior to these findings, rings of planetary debris, or "debris discs," around stars the size of the Sun had rarely been observed, because they are fainter and more difficult to see than those around more massive stars. Rocky planets arise out of large clouds of dust that envelop young stars. Dust particles collide and stick together until a planet eventually forms. Sometimes the accumulating bodies crash together and shatter. Debris from these collisions collects into giant doughnut-shaped discs. With time, the discs fade and a smaller, stable debris disc, like the comet-filled Kuiper Belt in our own solar system, is all that is left.Some solar system bodies from onther star?It is possible that some of the objects in the outer solar system actually formed around another star, calculations show: The alien worlds could have arrived through an interstellar trade that took place more than 4 billion years ago when a wayward star brushed past our solar system. The Sun's gravity could then have plucked asteroid-sized objects from the visiting star, while at the same time, the star pulled material from the outer reaches of our solar system into its grasp. This surprising conclusion was reached while scientists were working to explain the mystery object Sedna, a world almost as large as Pluto but located much farther from the Sun (see Update # 274 lead). Sedna's discovery in 2003 puzzled astronomers because of its unusual orbit - a 10,000-year-long oval whose closest approach to the Sun, 70 AU, is well beyond the orbit of Neptune.Understanding Sedna is a challenge because its orbit is far away from the gravitational influence of other planets in our solar system. However, the gravity of a passing star can pull objects beyond the orbit of Neptune, in the Kuiper Belt, into orbits like Sedna's. The detailed computer simulations show how this stellar fly-by likely took place and that two key requirements had to be met: First, the star must have stayed far enough away that it did not disrupt Neptune's nearly circular orbit. Second, the encounter must have happened late enough in our solar system's history that Sedna-like objects had time to form within the Kuiper Belt. The near-collision could have occurred when our Sun was at least 30 million years old, and probably no more than 200 million years old. A fly-by distance of 150-200 AU would be close enough to disrupt the outer Kuiper Belt without affecting the inner planets. |
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Mars UpdateMER - the scientific papers on Opportunity's first 90 days are out, while Spirit has found water-related goethite in the Columbia Hills, and Opportunity has left Endurance crater. The full papers via a Nature feature and related Cornell News, Texas A&M PR, JPL and NASA Releases, an MPCh PM [IDW]; also JPL, J. Gutenberg Univ. and Cornell Releases, Opportunity's view of its own heat shield, pictures 71... 13 (Spirit's view on Sol 332), 12 (look back at Endurance), 10 (Burns Cliff color pan!), 09, 07, 06 (Clouds over Endurance), 7083 and coverage of Dec. 21: S&T. Dec. 20: Dsc. Dec. 17: BBC, Guard. Dec. 16: NZ. Dec. 14: BBC, ST, NZ. Dec. 13: AB, FT. Dec. 9: UPI. Dec. 8: Nat'l G. |
Dec. 4:
Welt,
Bild
(German mass-circulation tabloid; this bs was a co-leader on the front page of the print edition).
Dec. 3:
AB,
HC,
Guard.,
ST,
NZ.
Dec. 2:
AB,
BBC,
SC.
Instruments for 2009 Mars rover selected - eight proposals to provide instrumentation and associated science investigations for the mobile Mars Science Laboratory: NASA, Cornell and Indiana Univ. Releases, Plan. Soc., AFP. HiRISE camera delivered for Mars Recon Orbiter: UA PR. The camera: details. Mars Express pictures may indicate recent volcanism - an FU Berlin PM, an ESA Release and coverage of Dec. 24: AP. Dec. 23: Guard., USAT, ST, ORF. Martian methane debate continues: AB. Scientists propose conservation parks on Mars, regulated just like national parks here on Earth: Nature. |
Saturn Update: Huygens released!The critical maneouver on Dec. 25 went according to plan; before on Dec. 13 Cassini had visited Titan again - and a distant flyby of Dione gave hi-res views. Pictures # 69 97, 96, 95, 65 58, 57, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34 (ring in gap), 33, 32, 29, 61 63 (Dione hi-res), 62 (Diona global), 60, 59, 58, 57, 56, 55, 54 (Titan global), 53, 52, 51 (Titan approach), 50, 58, 46 (Iapetus' dark side), 45 (Iapetus), 44 (ring animation), 43 (Prometheus/ring interaction), 42 (Mimas against clouds, ring shadow), ESA Releases of Dec. 25, Dec. 20, Dec. 14, Dec. 7 and Dec. 1, | JPL Releases of Dec. 24, Dec. 21, Dec. 16, Dec. 13 and Dec. 3, U. Colorado, USC [SN], Univ. of Iowa [EA], Georgia Institute of Technology, Gemini, Caltech (both on groundbased observations), NRAO (on planned Huygens tracking) and Alcatel (on the Huygens probe) Press Releases, the Huygens timeline, DISR test images (as if Titan was in Arizona :-) and coverage of Dec. 24/25: SN, BBC (earlier), FT, CNN, AP, AFP, Wired, Guard., ST, APOD, NZ. Dec. 23: FT, Welt. Dec. 22: FT, ZEIT. Dec. 21: BBC. Dec. 20: SciAm, Scotsman, SC. ST, NZ. Dec. 17: S&T, Nature, BBC. Dec. 16: FT, Cornell Chr., Plan. Soc., Welt. Dec. 15: ST. Dec. 14: BBC, USAT, S&T. Dec. 13: Dsc. (earlier). Dec. 9: AB. Dec. 3: BBC. Nov. 30: Dsc., BBC. Nov. 29: Plan. Soc., S&T. Nov. 28: Guard. Cassini observed solar storm arriving at Jupiter: PhysWeb, BdW. |
ISS etc. UpdateO'Keefe has resigned, the search for a successor is on, and a Progress is moving towards the ISS. The resignation letter, a news conference transcript, a GAO Report (summary) on STS cost uncertainties, NASA Releases of Dec. 22 (on the LRO payload) and Dec. 13, KSC Releases of Dec. 10 and Dec. 2, an ESA Release, a Univ. Bremen PM and coverage of Dec. 24: FT. Dec. 23: SN, FT, HC (other story), BBC, ST. Dec. 21: Welt. Dec. 20: AD, UPI. Dec. 19: SN (big package!), Space News, HC. Dec. 18: ST. Dec. 17: HC (earlier, other and another story), ST (other story). Dec. 16: HC, FT. Dec. 15: FT, HC. Dec. 14: S&T, HC (earlier), AD, FT, BBC, NZ. Dec. 13: Wired, FT, SpaceRev, ST. |
Dec. 12:
AW&ST,
HC,
ST.
Dec. 11:
SN,
FT
(earlier),
SR,
HC,
ST
(other story),
Welt.
Dec. 10:
HC,
AD,
Guard.
Dec. 9:
FT,
AFP.
Dec. 7:
HC,
Dsc.,
New Sci.,
ST.
Dec. 6:
SN,
FT,
SpaceRev.
Dec. 5:
HC,
ST.
Dec. 4:
FT
(sidebar),
ST.
Dec. 3:
FT
(other,
earlier stories),
SN
(other and
another story),
ST
(other story).
Dec. 1:
FT,
ST.
Nov. 30:
FT.
Nov. 29:
SN,
FT,
Space News,
ST.
The HST crisis - the N.A.S. panel recommends a manned servicing mission! A short Press Release [SN], the NAS report as a preprint, statements by Sen. Mikulski and Reps. Boehlert and Gordon and coverage & commentary of Dec. 17: FT. Dec. 16: UPI. Dec. 12: HC. Dec. 11: StarTrib. Dec. 10: S&T, FT, Welt. Dec. 9: Nature, AD, BBC, Dsc., HC, New Sci., SC, ST. Dec. 8: Wired, FT, USAT, HC, AFP. Dec. 7: ST. Dec. 6: FT. Nov. 27: FT. |
Deep Impact launch slips to Jan. 12because of a minor Delta problem - but the window lasts til Jan. 28: a NASA Release and coverage of Dec. 23: FT. Dec. 20: AB, Wired. Dec. 17: Plan. Soc. Dec. 16: Cornell Chr., Nat'l Geogr. Dec. 15: BBC, ST. Dec. 14: SN, FT. Nov. 28: SeattleT, SC.Rosetta camera images the Orion nebula during tests: MPS Release. NASA hopes to launch Pluto-bound craft in 2006 - while the mission is expected to receive enough plutonium to get to Pluto, scientific ambitions might have to be curtailed: FT. Telescope delivered for COROT satelliteThe prime contractor for the instrument will now be able to integrate the telescope with its baffle: Alcatel PR.Another exoplanet found with transit method and confirmed spectroscopically: paper by Konacki & al. Call for amateur exoplanet observations with the transit method: S&T. Discovering additional planets in transit timing data: papers by Holman & Murray and Agol & al. Scientific balloon search for antimatter lasted 8 daysAfter 8 days and 17 minutes, the flight of BESS-Polar, launched on Dec. 13 from McMurdo Station, Antarctica, was terminated after the balloon had circled the South Pole: KEK Release, tracking data, Guard.Supermassive black hole candidate in very distant quasar challenges formation theories: Chandra Release, NZ. SMBH in bulge-less quasar galaxy: NRAO Press Release. Observing AGN in polarized light: PPARC PR. XMM finds yet another class of AGNs, the XLEOs (X-ray Line Emitting Objects): ESA Release. Subaru watches galactic cannibalism: Press Release. No huge amounts of dust in Cas AAn earlier detection was actually caused by dust in the line of sight: a paper by Krause & al., a U of A PR and a MPG PM.An unexpectedly cool neutron star in the supernova remnant 3C58 raises questions about the nature of neutron star matter: Chandra Release.
Oscillations in the solar corona confirmedduring observations at the 2001 total solar eclipse with the SECIS experiment: a paper by Katsiyannis & al. Ultrasound in the solar atmosphere: SwRI Press Release, pictures, SciAm, SC. Plus SOHOs best movies.Sun storms hit comet - three different coronal mass ejections in 2002 caused wobbles in the tail of comet Ikeya-Zhang: Nature. 'Haloween storm' compressed van Allen belts: BdW. High-speed flows in the magnetotail: ESA Release. Interstellar helium coming towards us: Science@NASA. Gravitation anomalies during solar eclipses? The bizarre story won't go away: a review by Duif, BdW. A speculative model for the interior of Jupiterin which the Jovian core is originally tar and rock, steadily growing to the point where it accretes gas from the solar nebula, supposedly fits the Galileo probe data better than the standard view: Wash. Univ. PR.Amalthea didn't form where it is now in its orbit around Jupiter, groundbased spectra suggest: Subaru Release. Jupiter occultation by the Moon on Dec. 7 imaged: gallery, S&T. Small Moon @ Xmas: Science@NASA. Rare planet vista in the morning now: Nat'l Geogr. Rare 'line' of planets in mid-Dec.: S&T PR. |
Delta 4 Heavy launched!On Dec. 21 the world's strongest rocket has finally lifted off, though only with a dummy payload - which didn't even reach the full orbital height. The status, a blog, launch galleries 1, 2, 3 and 4, a Boeing PR and coverage of Dec. 22: SN (earlier), FT (earlier), Dsc., BBC, ST, NZ. Dec. 21: USAT, FT. Dec. 20: Welt. Dec. 13: BBC, ST. Dec. 12: FT. Dec. 11: SN, BBC, ST. Dec. 10: FT, ST. Dec. 9: SN. Dec. 8: ST. Dec. 7: SN, FT. Dec. 6: Dsc., Space N.Ariane 5 launches Helios, Parasol and 5 more satellitesAn Ariane 5 booster successfully launched seven satellites on Dec. 18, including a French reconnaissance satellite: Arianespace, Alcatel and ESA Press Releases, AFP, ST, NZ - and an earlier CNES story on Parasol. The Ariane ECA troubles: BBC (earlier), Welt. Financing of Soyuz pad in Korou: AFP.Japanese H-2A flights to resume in 2005: ST. Japan's troubled Moon program: AFP. Bold space plans in India: AW&ST. Europa proposed as cosmic ray detectorJupiter's ice-covered moon Europa could one day serve as a giant detector for high-energy particles from space: a paper by Gorham, New Sci. The APS Neutrino Study: a paper by Barwick & al. Antarctic AST/RO discovers starbursts in Milky Way: Antarctic Sun.Russia's first robotic telescope is now operational: the homepage of MASTER and a paper by Lipunov & al. LuckyCam: Press Release. WFCAM @ UKIRT: JACH PR, BBC. Another Mauna Kea law suit: Honol. Adv. Bush fires threatened Parkes radio telescope in Australia, but the danger has passed: S&T. Radio survey with the ATCA: ABC. Yerkes Observatory about to be sold?The University of Chicago has considered selling the telescopes, buildings and property for decades - now a sale seems imminent, and it remains unclear what the future holds: S&T. Mt. Wilson Obs. founded 100 yrs ago: BBC.First mirror for giant optical telescope ordered from the Mirror Lab, but the financial situation of the "GMT" isn't exactly clear - nor is the actual purpose of mirror #1: Carnegie Inst., U of AZ and CfA Press Releases. Chile's president has fun at ESO: PR. Virtual Solar Observatory now available for "one-stop data shopping" - the VSO makes it possible to access data from multiple sources, even ones you didn't know existed: NSO Press Release. Europe's GRID to sift solar data: ESA Release. New solar telescope for BBSO with 1.6 m aperture: SPX. ATST plans: Nat'l Geogr.
Da Vinci delays launch attempt to JanuaryThe da Vinci Project has pushed back a launch attempt of its suborbital spacecraft to January: ST. But the balloon is ready: Press Release [SR]. Canadian Arrow also continuing: UPI. Virgin Galactic visions: Guardian.European space program(me) gets organized - first summit held: ESA, EC Releases, NZ. Aurora rising? ESA Release, ST. EU pushes ahead on Galileo: EU Release, BBC, ST. Four s/c ordered: ESA Release, BBC, ST. White House releases GPS policy that could allow the government to shut down the system in the event of a national crisis: ST. An extremely high proper motion, ultracool subdwarftravelling through the vicinity of the Sun but belonging to the halo: a paper by Scholz & al. and an AIP PM. Very low-mass, newborn brown dwarf found in Chamaeleon I cloud complex: Gemini Release.Complicated structures in two planetary nebulae have been studied with Hubble & Subaru: HST, Vanderbilt and Subaru Press Releases, Dsc. Stellar clusters forming in blue dwarf galaxy NGC 5253: ESO PR, BdW. Dark hydrogen in the outskirts of galaxy NGC 4414: BdW. |
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
