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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion! (SuW version) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
30 years ago Luna 16 returned samples from the Moon in the first automated sample return from another celestial body: Universe Today. How to preserve the Apollo 11 landing site: Discovering Archaeology. Astronauts should be allowed to own Moon rocks: Space.com.
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TRACE clues to the coronal heating mechanismThere have been too many claims to count in the past few years alone that this or that telescope, spacecraft or experiment performed during a solar eclipse had finally solved the mystery why the solar corona is so much hotter than the solar surface below - here is at least a crucial clue to where the heating takes place. New observations by the TRACE satellite have revealed that most of the heating occurs low in the corona, within about 15,000 km from the Sun's visible surface. The gas fountains form arches, hundreds of thousands of km high. As gas emerges from the solar surface, it's heated and rises, then cools and crashes back to the surface at more than 100 km/s.Millions of different-sized coronal loops comprise the corona, and a 30-year-old theory assumes the loops are heated evenly throughout their height. The TRACE observations show that instead, most of the heating must occur at the base of the loops, near where they emerge from and return to the solar surface. The old theory of uniform heating predicted that the loops would be substantially hotter at their tops because gas at the top of the loops is thinner, and does not radiate heat away as efficiently as the dense gas near the bottom. If the loop were heated evenly over its entire height, the top, which can't lose heat as well, would become hotter than the rest. Earlier, less-detailed observations of the coronal loops could not confirm nor invalidate the uniform heating theory because they could not reveal that the loop tops were really about the same temperature as the bases. However, the high-resolution TRACE pictures show that what was thought to be one coronal loop is actually a bundle of thin, individual loops. Although some thin loops in the bundle are hotter than other spirals, precise measurements by TRACE show that, over its height, each separate, thin loop varies much less than the uniform heating theory predicts. Since a loop loses heat most rapidly from its bases, most of the heat must also be going in at the bases for the loop to be at a uniform temperature: an observation that could eventually lead to an explanation of the heating mechanism itself. |
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GRB blast wave resolved by microlensingThe expanding blast wave of a Gamma Ray Burst has been spatially resolved for the first time, due to a chance alignment of the distant explosion with a foreground star: The gravity of the latter has amplified the light from the GRB in a distinctive way that is now allowing to test models of the GRB blast wave. The object, dubbed "GRB 000301C," had been discovered in March 2000, and it had become clear soon that a microlensing event - as it has been observed many times in the Galaxy - was underway as well.In addition to being able to show that a GRB blast wave appears as a ring, as predicted by some models ("This discovery really confirms what we thought a gamma-ray burst shock should look like"), information about the object that magnified the burst could also be derived: It was an ordinary star, with perhaps half the mass of our Sun. The observed data perfectly fit the model for a ring structure which is expanding faster than the speed of light, an illusion caused by the viewing geometry from Earth. |
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NASA Announces Small Explorer (SMEX) SelectionsNASA has now made selections in the Explorer Program from proposals submitted in response to a recent Announcement of Opportunity for Small Explorers (SMEX) and Missions of Opportunity. Seven SMEX proposals and one Mission of Opportunity proposal were selected for concept studies, and one Mission of Opportunity proposal was selected for flight. The seven SMEX's selected for study are:
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First light for the 1st Magellan telescopeThe first of twin 6.5-meter Magellan telescopes in Chile marked "first light" on September 15, with a formal dedication planned for December and the start of science observations next February: 1st Light Press Release, U of A Press Release, a few pictures and a SpaceViews story.Observations with the "new" MMT have also begun in earnest after the Arizona monsoon season is waning - the former Multiple Mirror Telescope had received another one of the "mass produced" 6.5-m mirrors from the Steward Obs. Mirror Lab in spring: UA Press Release. 6-meter Liquid Mirror Telescope to become operational later this year: Space.com. HST movies show outflows from young stars in action!Time-lapse movies made from a series of pictures taken by the Hubble Space Telescope of XZ Tauri and HH 30 show that young stars and their surroundings can change dramatically in just weeks or months: STScI Release, CNN, Space.com.Palomar Testbed Interferometer watches Cepheid pulsate - to make this observation of Zeta Geminorum, astronomers combined the light received from two small telescopes situated 110 m apart to mimic the performance of a very much larger device: Press Release, BBC, Space.com, SpaceViews, PTI Homepage. Stellar orbits tracked around the Galactic CenterFor the first time ever, astronomers have seen stars accelerate around the Central Engine of our galaxy - the IR sources had been seen for years, but now it's also evident that they are on strongly curved orbits around the 2.6m solar mass object: the full paper, a Nature Science Update, UCLA and Keck Press Releases, a picture and BBC, Discovery, Fox, Space.com, AP, SpaceViews stories.A radio 'movie' of a collision between a galaxy's jet and a gas cloud has been generated from VLBA data and should help to understand the vicinity of galactic central engines: NRAO Press Release, Space.com, BBC. Big ice deposit spotted on Mars?Researchers have spotted what they suggest is a near-surface ice reservoir, about the size of Arizona, located in the Solis Planum region, south of Mars' Valles Marineris - a conclusion based on the morphology of impact craters: Space.com - this was reported one year ago in Update # 152 story 3 sidebar 2, by the way. Mars in 3D: Planet 3D News, Space Daily."Mars 2001 Odyssey" will be the name of NASA's next Mars orbiter: JPL and NASA Press Releases, SpaceViews, SPIEGEL. The difficulties of planning future Mars exploration: NSU, Space.com. A campaign to save the abandoned 2001 lander: Homepage, Space.com. Hopping robots for Mars: Space.com. Deciding where to land: Space Daily. How dust grains can form planets has been studied in a German space shuttle experiment: Nature Science Update. Tons of current Jupiter images from September by the Schulstw. Gudensberg. Dnepr launches 5 microsatellitesA Russian Dnepr booster successfully launched five microsatellites from Italy, Malaysia and Saudi Arabia into low Earth orbit on Sept. 26 - the launch was the second for the converted SS-18 "Satan" ICBM, a missile being phased out under arms control treaties: Space.com, Interfax, Spaceflight Now, SpaceViews.ESA satellite kicked off Japanese rocket - the H2A will launch without a payload instead: Reuters, AFP. Iran test-fires missile, says the Shahab-3D is for launching satellites and has no military purpose: AP. Shuttle replacement X-33 will fly in 2003 the earliest - and it will use an aluminum tank instead of the over-ambitious composite material that failed in a test: MSFC Press Release, Fla. Today, SpaceViews. Earlier: AP. |
Early NEAR science: Eros an ancient, rock-strewn bodyScientists analyzing data from NEAR have concluded that the near-Earth asteroid Eros is a body that dates back to the formation of the solar system and it littered with a surprising amount of rocky debris: JHU, Cornell, GSFC, JPL Press Releases, a special MIT page on Eros' shape, and coverage by SpaceRef, SpaceViews, AP, Space.com. NEAR has spotted square-shaped craters on asteroid Eros, a telltale sign of mysterious goings-on in the asteroid belt long ago: Science@NASA, Space.com.More reports about the NEO report from the UK: BBC, AFP, SPIEGEL, Discovery, AP, SpaceViews, RP. ACC wants the 3-m telescope built in Liverpool: Space Daily. A Good month for asteroids - asteroid hunters have enjoyed a close-up look at two new potentially hazardous space rocks as they passed close to the Earth in September: Science@NASA. ASCA satellite all but given upJapanese space agency officials have all but given up efforts to recover the orbiting x-ray observatory that went into a safe mode in July indirectly caused by strong solar storms: SpaceViews, Spacefl. Now.Chandra splits Sirius B,A - seeing Sirius A was rather unexpected: NASA Release. Amateur and professional astronomers team up for Chandra observations of SS Cygni: Chandra Chronicle. A detailled preview of the next ISS visithas been prepared by Spaceflight Now - the 100th shuttle flight will be packed with dramatic space work. The launch on Oct. 6 at 1:38 UTC has now been confirmed: KSC Release, SpaceViews, Fla. Today, CNN.Atlantis is back after a night landing on the morning of Sept. 20 - Status Reports # 25, 24, 23, 22. Coverage on Sept. 23: Fla. Today. Sept. 22: AP, Fla. Today. Sept. 21: Space.com ( story archive). Sept. 20: AFP, BBC, AP, CNN, Space.com, Reuters, SpaceViews, Houston Chron., Spaceflight Now, Fla. Today, RP, SPIEGEL. Sept. 19: Fla. Today, Space.com, AP. Unity's backup will become ISS Propulsion Module - the so-called "Node X", based on a structural test article built during the assembly of the Unity module, will be used starting later this decade to help reboost the station and maneuver it around any orbital debris: Fla. Today, SpaceViews. NASA, "Dreamtime" relationship sours - the company that's to market multimedia content from the ISS apparently has made overblown claims, including the announcement of a win-a-trip-to-the-ISS contest: Space.com, NYT. Dreamtime delivers equipment: Space.com. Next commercial Mir mission streamlinedbecause of MirCorp funding problems - a 3rd Progress will be paid for, but the next manned visit will last only 2 weeks: MirNews, Space.com, Interfax, Space Daily, MirCorp Rel., SpaceViews, AvNow. Wanna go too? Register here ... (and see also these Space.com and NYT stories)! James Cameron wants to visit Mir, too: Interfax, Space.com. Sending people into space is suddenly very popular: SpaceRef.Chinese astronauts train in Russia, but the next Shenzhou launch - next month? - will be unmanned: AP. China to develop new generation of rockets with view to Moon landing: Space Daily. NASA names Israel's 1st astronaut who will fly aboard space shuttle Columbia next summer on a research mission: AP.
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The U.S. site of this Cosmic Mirror has been visited
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Compiled and written by Daniel Fischer
(send me a mail to [email protected]!), Skyweek
