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| Monster Issue Today |
Sep 17, 2003 - It's a monster six-story edition of Universe Today. Take your time with this big guy. Thanks to everyone who joined the Chinese Human Launch pool I set up yesterday. I've only got about 15 guesses so far, so there are still lots of gaps available. Why don't you stop by and make a guess?
As I mentioned a week ago, I've started incorporating full press release information into Universe Today. I've been going back through the archives and fixing them into the same format, and I'm blown away at how many dead links there were. It's pretty sad how people don't leave material on the web for any duration. :-( It's going to be some detective work to piece them together.
Fraser Cain
Publisher
Universe Today |
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| Image credit: NASA/JPL |
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| Galileo's Final Study of Jupiter |
| Sep 17, 2003 - We're only days away until Galileo's final plunge into Jupiter on September 21. Nearly out of fuel, the spacecraft was put onto a collision course with Jupiter to prevent it from accidentally crashing into Europa and potentially contaminating it with Earth-based bacteria. The entry point on Jupiter will be 1/4 of a degree south of its equator and it will strike the planet at 174,000 km/h - obviously it'll be destroyed almost instantly. Scientists hope to retrieve every piece of data they can, but the radiation will intensify to immense levels as the spacecraft nears the planet, so it might not be possible. |
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| Image credit: Hubble |
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| Astronomers Find a Transparent Galaxy |
| Sep 17, 2003 - It turns out that a collection of stars orbiting the Andromeda galaxy are actually the remnants of another galaxy being torn apart and consumed, according to new research from astronomers at Case University. They only realized it was a separate galaxy after charting the velocities of several of its stars. Astronomers failed to detect it before now because much of the galaxy is located in front of Andromeda's bright galactic disk. The discovery will give astronomers further evidence to support the theory that smaller galaxies merge together to form larger, more complex galaxies. |
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| Original Source: NASA Illustration |
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| Iron Can Help Determine if a Black Hole is Spinning |
| Sep 17, 2003 - Astronomers have used the Chandra X-Ray Observatory to examine the presence of iron in three stellar black holes to understand if they're spinning or not. In theory, a spinning black hole will drag space around it and permit atoms to exist closer than a non-spinning one - Chandra can detect the relativistic effects on iron atoms orbiting the black hole. The explanation for different spin rates could be due to the size of a black hole's source of material; the larger the source (like a big star) and longer feeding time, the faster the black hole spins. |
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| Image credit: Hubble |
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| More Evidence for Dark Energy |
| Sep 17, 2003 - Astronomers have studied the light from 11 new supernovae to help validate the evidence that some kind of "dark energy" is accelerating the Universe apart. The supernovae are a special type called Ia, which are known to be roughly the same brightness. By measuring their relative brightness, they can calculate how distant the Type Ia supernovae are. This latest data was gathered by an international team of astronomers using ground telescopes to provide followup targets for the Hubble Space Telescope. A new satellite is planned, called the SuperNova/Acceleration Probe, which will be able to discover thousands of supernova and track their explosions precisely. |
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| Image credit: ESA |
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| Are We Safe from Gamma Ray Bursts? |
| Sep 17, 2003 - Gamma ray bursts (or GRBs) are the most powerful known explosions in the Universe. Although astronomers aren't exactly sure what causes them, they're somehow linked to supernovae explosions - it could be the formation of a black hole after the supernova explodes. When a GRB goes off, it funnels a tremendous amount of energy into two lighthouse-like beams that would probably vaporize anything out to 200 light-years away. Fortunately there aren't any stars in our galactic neighborhood that has the potential to explode as a supernova, so we're probably safe from such an event, but astronomers will keep looking… just to be sure. |
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| Image credit: PPARC |
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| New Evidence About the Formation of Galaxies |
| Sep 17, 2003 - Astronomers have long believed that galaxy formation in the early Universe was a spectacular event, with smaller groups smashing together to form larger elliptical galaxies, and star formation would have been everywhere. New data gathered by the SCUBA telescope help support this theory. A team of UK astronomers have captured images of galaxy formation 12 billion years ago, at the very limits of today's astronomy. Their data will help astronomers understand how simple elliptical galaxies formed to help build models that could eventually help to explain how more complex spiral galaxies (like our own Milky Way) could have formed. |
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