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  Supermassive asteroids (sorta); Yuri's NightApr 14, 2012 8:15 AM PDT | url
 
Added 1 new A* page:Hey, it's a name! I didn't have it in this conversation at first, but then I came up with what I thought was a dandy name for him, and wanted to get it out there (it's so much easier to talk about a character if they have a name, after all), so I rather tacked it on to Selenis' line here. Ah, dirty tricks!
 
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I'm not sure how old it is, since NASA's image feature page doesn't have a date on it, but this artist's rendering of an asteroid field around supermassive black hole Sgr A* at the center of the Milky Way was their "Image of the Day" at some point. It seems to me the asteroids are way larger than actual scale, but I guess that was to make them easier to see. The reddish color of the gas and dust around the event horizon would be due to everything being redshifted as it is sucked away faster and faster into the black hole--until it reaches the even horizon, of course, at which point not even photons can scatter back to show us what's going on; although this rendering doesn't appear to be attempting to incorporate phenomena such as gravitational lensing or other crazy effects that could very well be showing up in such unimaginably extreme conditions:
 
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The accompanying text is pretty interesting--it's actually pretty hard to find any clear descriptive text on the internet about the hot space in the near vicinity of our galaxy's central supermassive black hole, but this is a decent chunk:

A new study provides a possible explanation of mysterious X-ray flares detected by the Chandra X-ray Observatory for several years in the region of Sagittarius A*, or Sgr A*. The study suggests a cloud around Sgr A*, a supermassive black hole at the center of our Milky Way Galaxy, which contains hundreds of trillions of asteroids and comets that have been stripped from their parent stars. The flares occur when asteroids of six miles or larger in radius are consumed by the black hole. An asteroid that undergoes a close encounter with another object, such as a star or planet, can be thrown into an orbit headed towards Sgr A*. If the asteroid passes within about 100 million miles of the black hole, roughly the distance between the Earth and the sun, it is torn into pieces by the tidal forces from the black hole. These fragments would then be vaporized by friction as they pass through the hot, thin gas flowing onto Sgr A*, similar to a meteor heating up and glowing as it falls through Earth's atmosphere. A flare is produced and eventually the remains of the asteroid are swallowed by the black hole.

 
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Oh yeah, and I was just informed by someone more alert than I that yesterday, April 12th, was "Yuri's Night"; since I know nothing about this I'm just gonna roll in some Wikipedia:

Yuri's Night is an international celebration held on April 12 every year to commemorate space exploration milestones. The event is named for the first human to launch into space, Yuri Gagarin, who flew the Vostok 1 spaceship on April 12, 1961. In 2004, people celebrated Yuri's Night in 34 countries in over 75 individual events. Locations have included Los Angeles, Stockholm, Antarctica, the San Francisco Bay Area, Tel Aviv, Tokyo, and the International Space Station.

 
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image by Jcranfordteague (source)
 
So there we go! Not that I'll remember this next year or anything, although last year I did manage to mention several times, more and more belatedly, that it had been the 50th anniversary of Gagarin's flight. But if you want to be more responsible than me you can keep tabs on this stuff on the Yuri's Night site, yurisnight.net.
 
 
 
 
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