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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 |
in early reports while others call it rather bright - oh well ... The eclipse - the last until 2007 - could be seen, weather permitting, in the Americas, Europe and Africa: a gallery, archived webcasts, individual results by Karrer, Br�ckner, Pikhard, Souza, Valentin, Espenak, Ramirez, Gaehrken, Bruenjes and the WDR and coverage by S&T, FT and SC. Previews: Espenak, S&T, Science@NASA, FT, AFP, HC, AB, SC, WDR - and info about stellar occultations during the eclipse. Partial solar eclipse on Oct. 13/14 (UTC): pictures from Hawaii (one more), Korea, a gallery and some reports. Sun sometimes spot-free these days: Science@NASA.
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Bronze age sky disk on display - in contextThe amazing 3600 years old "Sky Disk" unearthed in Germany five years ago and finally impounded and made available to research in early 2002 (see Updates # 236 and 243) is now the centerpiece of a stunning exhibition at the Landesmuseum f�r Vorgeschichte in Halle (Saale), Saxony-Anhalt, Germany. Freshly restored - some might argue over-restored - it is on display surrounded by many of the best artefacts of European bronze age cultures that frame the disk's complex symbolism in a wider context. And while the meaning of the astronomical motives is not known for sure - and probably never will be - there is now a plausible hypothesis that agrees both with the archaeological and cultural record as well as celestial mechanics.In this view, which nearly all scientists directly involved in studies of the disk subcribe to, the original artist wanted to show the star cluster of the Plejades, framed by the Moon in two different phases, as full moon and as a waxing crescent. The Plejades are depicted as seven dots, not as they really look like but as an abstract symbol which was in use widely in that era. The other stars do not represent any real constellations, just the starry sky background - this is the earliest known (somewhat) realistic depiction of the Universe. Why the Plejades and the two views of the Moon? Because 3600 years ago there were obvious conjunctions of the cluster with the Moon in these two phases in the evening sky in March and October, crucial months for agriculture: The disk may well highlight these two dates. Later, though, it was changed repeatedly (and by at least one different artist, as details of the inlays show): First some stars were moved to allow the installation of the two horizon arcs that span exactly the distance between the northern- and southernmost points of sunset and sunrise from Saxony-Anhalt in the bronze age. Even the slight shift of these points towards the North (due to the finite size of the solar disk and atmospheric refraction) is displayed correctly on the disk where the two arcs are not precisely opposite to each other. Thus real measurements on the sky were incorporated, though the disk itself seems unsuitable for actual astronomical use and probably stayed a cultish object throughout its life. In a further change, a third arc with lots of tiny 'feathers' was added at the bottom: This feature very closely resembles depictions of ships at that era, with the feathers representing the rudders. Intriguingly those ship pictures were common in Northern Europe while the inlaying technique used by the disk makers - known as incrustation or Tauschierung in German - is very typical for the Mediterranean and otherwise unknown in Central Europe at that time: The disk thus represents a unique interaction of cultures. The ship is also the only non-astronomical element among the disk's motives and is most likely a mythological one: Such 'Sun barges' were believed to carry the Sun from West to East at night. The final change made to the disk was the punching of holes all around its edge, perhaps to mount it somewhere. Eventually it was buried in a manner otherwise used for important people, together with other artefacts such as swords. (On one of the latter recently traces of organic material were found that finally permitted radiocarbon dating: The result of 1600 BCE matches the age estimate from the swords' style perfectly.) And now the disk is back in the spotlight: in Halle until April 24, 2005, then in Copenhagen, in 2006 in Mannheim (Germany) and then permanently in Halle. The Cosmic Mirror strongly recommends having a look at this amazing artefact and the fine exhibition developped around it! |
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Terrestrial planet formation observed in many circumstellar disksPlanets are built over a long period of massive collisions between rocky bodies as big as mountain ranges: New observations from NASA's Spitzer Space Telescope reveal surprisingly large dust clouds around several stars. These clouds most likely flared up when rocky, embryonic planets smashed together. Spitzer was able to see the dusty aftermaths of these collisions with its powerful infrared vision. When embryonic planets, the rocky cores of planets like Earth and Mars, crash together, they are believed to either merge into a bigger planet or splinter into pieces. The dust generated by these events is warmed by the host star and glows in the infrared, where Spitzer can see it. The findings mirror what we know about the formation of our own planetary system: Recent observations from studies of our moon's impact craters also reveal a turbulent early solar system.Spitzer looked for dusty discs around 266 nearby stars of similar size, about two to three times the mass of the sun, and various ages. Seventy-one of those stars were found to harbor discs, presumably containing planets at different stages of development. But, instead of seeing the discs disappear in older stars, the astronomers observed the opposite in some cases. This variability implies planet-forming discs can become choked with dust throughout the discs' lifetime, up to hundreds of millions of years after the host star was formed: The only way to produce as much dust in these older stars is through huge collisions. Before Spitzer, only a few dozen planet-forming discs had been observed around stars older than a few million years. Spitzer's uniquely sensitive infrared vision allows it to sense the dim heat from thousands of discs of various ages. |
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Genesis crash likely explained: gravity-switch mounted upside-down ...The Mishap Investigation Board (MIB) has identified a likely direct cause of the failure of Genesis' parachute system to open. The parachute system failed to deploy when Genesis returned to Earth September 8, 2004 (see Update # 280). The MIB, analyzing the Genesis capsule at a facility near Denver, said the likely cause was a design error that involves the orientation of gravity-switch devices. The switches sense the braking caused by the high-speed entry into the atmosphere, and then initiate the timing sequence leading to deployment of the craft's drogue parachute and parafoil. This single cause has not yet been fully confirmed, though, nor has it been determined whether it is the only problem within the Genesis system.Meanwhile, scientists unpacking samples at NASA's Johnson Space Center (JSC), Houston, curation facility remain upbeat in their assessment of the prospects for obtaining useful science from the recovered samples. The facility counted more than 3,000 tracking numbers for the containers that hold pieces of wafers from the five collector panels. The panels secured samples of atoms and ions from the solar wind that were collected during Genesis' nearly three-year mission in deep space. Some of the containers hold as many as 96 pieces of the wafers. The team has been preparing the samples for study since the science payload and recovered samples arrived at JSC October 4. |
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Saturn Update: Titan close-ups, radar pics!The first close-up images and clips from a long radar scan of Titan have been returned by Cassini after its Oct. 26 flyby, unveiling an extremely diverse and world - and images of Tethys from Oct. 28 beat Voyagers'. The Titan pictures, the Tethys pictures, JPL Releases of Oct. 29, Oct. 27, Oct. 26 and Oct. 25, a JPL Press Kit for the flyby, ESA Releases of Oct. 28, Oct. 27 [alt.] (earlier), Oct. 26 and Oct. 21 and PPARC (earlier), UA [SN], LANL, Berkeley, Plan. Soc., NASA and Univ. K�ln Press Releases. | Pictures # 69 88 (amazingly confusing radar view), 87 (Titan's haze), 86 (radiometry), 85 (streals on the surface), 84 (another radar view), 83 (VIMS view), 82 (VIMS close-up), 81, 80, 65 08, 07, 06, 05, 04, 03, 02, 64 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 61 39 (false color), 37 (approach movie), 36 (Huygens landing site), 25 (hi-res hi-contrast!), 24 (hi-res movie!), 23, 22, 21, 20, 16 and 07 (full disk hi-contrast) [SN] and coverage of Oct. 30: Wired. Oct. 29: Nature, New Sci., BBC, FT, CSM, ST. Oct. 28: S&T, BBC, FT, HC (earlier) USAT, UPI, AB (other story), CSM. Oct. 27: SN, AB, FT, BBC, Wired, Nature, Dsc., BDC, AFP (earlier), New Sci., Times, AP, ST, NZ. Oct. 26: FT, Reg., SN, BBC, Dsc., HC, SR, NZ. Oct. 25: FT, New Sci. Oct. 22: Nat'l Geogr. Oct. 19: AFP. Oct. 15: BdW. Oct. 13: Dsc. Oct. 11: AB. |
Mars UpdateMars Express methane paper in press, called the "clearest indicator of the possibility of life on the Red Planet": U Mich. PR [SD]. Mars insolation history: Obs. de Paris PR [SR]. Evidence for Mars quakes? SwRI PR [SR], pictures. |
Mars meteorites and Mars history:
Yale PR
[SR].
The MER have delivered 50,000 pictures, far more than all other Mars landers combined. JPL Releases of Oct. 29 and Oct. 21, Virginia Tech PR and coverage of Oct. 27: SC. Oct. 23: ST. Oct. 22: New Sci. Oct. 18: AB. Oct. 15: UPI, SC. Oct. 13: Dsc. Oct. 11: Chic. Tr., APOD. MRO in final assembly: SC. |
ISS etc. UpdateExpedition 10 has relieved Exp. 9 on the station, while May '05 is now the target time for STS RtF. NASA Releases of Oct. 29, Oct. 25, Oct. 13 and Oct. 12, an ESA PR on the Columbus Control Ctr., a NASA Picture of the Soyuz launch, Kerry4President on JFK's space agenda, an open letter by W. Hale on STS risks and coverage of Oct. 30: HC, BBC, AFP, ST, NZ. |
Oct. 29:
FT,
SR.
Oct. 28:
FT,
ST.
Oct. 27:
FT,
AP.
Oct. 26:
ST.
Oct. 25:
SpaceRev.
Oct. 24:
BBC,
FT,
SR,
HC
(earlier),
AFP,
ST,
NZ.
Oct. 23:
SN.
Oct. 22:
SN,
FT.
Oct. 21:
FT,
Welt.
Oct. 20:
FT,
UPI,
SC,
NZ.
Oct. 19:
SR.
Oct. 18:
SpaceRev,
HC,
ST.
Oct. 17:
FT,
AP.
Oct. 16:
SN,
BBC,
FT,
AFP,
ST.
Oct. 15:
FT.
Oct. 14:
New Sci.,
FT,
SR,
ST,
NZ.
Oct. 13:
SN,
FT
(also on the
crew),
HC,
ST,
NZ.
Oct. 12:
Dsc.
Oct. 11:
SN.
The HST crisis - coverage of Oct. 21: SC. Oct. 18: AD. |
Swift launch slips againto approx. Nov. 11 thanks to a faulty third stage rocket on an unrelated launch: Register. Further previews: FT, Guard., BBC.DART launch scrubbed until further notice - the rendezvous demonstrator was contaminated: Status, NASA (earlier [SD], still earlier, even earlier, still earlier) and KSC Releases and coverage of Oct. 28: FT, ST. Oct. 26: FT, ST. Oct. 24: FT. Oct. 22: New Sci. Chinese return capsule crashes into house!A Chinese satellite smashed into a villager's house on its return to earth on Oct. 15, destroying the dwelling but causing no injuries - it was the recoverable section of a probe launched to carry out scientific experiments in space: Xinhua, AFP, BBC, AP, ABC, SD, ST. Brazil launches suborbital rocket: BBC.Tentative choice for big Sun telescope siteThe 4-m-ATST will probably be built on Haleakala atop Maui, Hawaii: IFA Press Release.Robotic telescope built from 2MASS instrument, will join robotic scopes triggered by Swift: CfA Release. UK Astrometry and Photometry Programme (UKAPP) for Near-Earth Objects also using robot scope: BBC. Meet the NPOI, a pioneering optical interferometer: CSM. Chinese plans for a solar observing satellite in 2008 have been detailled: Xinhua. Way beyond the Terrestrial Planet Finder: Guard. Perseid impact imaged on the Moonthis August 11 - it is the first non-Leonid impact on the lunar surface ever recorded on video: Special Page. Orions should have peaked on Oct. 21: S&T, Science@NASA.Speculations about invisible comets - based on a lack of visitors from the Oort Cloud - will be resolved by the WISE satellite: Armagh and Cardiff Press Releases, Nature. Don't believe everything you read: NEO News. Unconfirmed impact crater field in Bavaria making headlines: AFP [SD]. Surprises is the Bosumtwi crater: FNF. Impact frequencies: SciAm. |
Frame-dragging by Earth observed?The orbits of the LAGEOS satellites drift over time, but influences other than General Relativity are hard to subtract: NASA Release (more), Nature, S&T, BBC, New Sci., ST, NZ.Polarization of the CMBR measured better than ever with the CBI: Caltech PR (more). z=10 galaxy again not confirmed: Gemini PR. Virgo cluster dynamics studied with the help of intergalactic Planetary Nebulae - the galaxy cluster is far from relaxed: ESO PR. Spitzer finds 'nearby' globular clusterWith a distance of 'only' 9000 ly this ancient star cluster is closer than most other globulars - and only the IR satellite (and 2MASS, it turns out) could spot it: a paper by Kobulnicky & al., a JPL Release, an APOD and coverage by S&T, Casp.StarTr. and ST.A new Milky Way companion, an overdensity of resolved blue stars - is it an unusual Globular Cluster or an Extreme Dwarf Satellite? A paper by Willman & al., an SDSS Press Release, SC. Most of the MW satellites not related to dark-matter dominated satellites: a paper by Kroupa & al. How certain stars get & keep their B fields has finally been solved mathematically - the magnetic fields are primordial: MPG Press Release [SD; German original]. Stars near Sun on strange orbits, perhaps pushed by density waves: ESA PR, New Sci.
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Compiled and written by Daniel Fischer
