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View Full Version : Discussion: How to Find a Black Hole



Fraser
2003-Nov-27, 09:41 PM
SUMMARY: A black hole's gravity is so intense that nothing, not even light can escape it - that makes them pretty much invisible to astronomers. That doesn't mean astronomers can't find them, though, as black holes have a powerful effect on their environment. One way to spot a black hole is the gravitation effect it has on nearby objects; stars have been found orbiting a spot in space so quickly, it could only be a black hole. When matter is just about to be consumed by the black hole, there is also a powerful burst of radiation that can be seen from Earth-based observers.

View full article (http://www.universetoday.com/am/publish/matter_flare_black_hole)

What do you think about this story? Post your comments below.

trekgoddess
2003-Nov-28, 02:21 AM
If a black hole sucks up all the energy, including light and heat, then wouln't the "last cry" be emersed in the hole also? Or do I just not understand enough theoretical astrophysics to get the concept right?

Cygnus X-1
2003-Nov-28, 11:51 PM
In the case of a binary star-black hole system, the " last cries " are x-rays ( high frequency light ). They come from the gas being sucked into the black hole from the companion star. Approaching a black hole, there is a threshold where indeed nothing can escape, called the event horizon. As the gas gets closer, it is heated to the point of emmiting x-rays before eventually reaching the event horizon. Even black holes have limits. The matter, light, whatever, has to get close enough reach the point of no return. " The x-ray is her siren song...." :)

trekgoddess
2003-Nov-30, 05:32 PM
thanks Cygnus, but I still need to read more Hawking before I'll completely understand

umesh
2004-Jan-19, 11:56 AM
Originally posted by trekgoddess@Nov 28 2003, 02:21 AM
If a black hole sucks up all the energy, including light and heat, then wouln't the "last cry" be emersed in the hole also? Or do I just not understand enough theoretical astrophysics to get the concept right?
[FONT=Impact][SIZE=7][COLOR=red]tell me where really is this blackhole's role out there for the stability of universe, can this massive thing grow and incase of them being sucking everthing how some of them emitting characteristic radiations.

VanderL
2004-Jan-19, 12:57 PM
" the ship cannot resist her long"
Has it been shown that matter, before it is heated and mashed by the gravity of a black hole, is really moving towards it?
Cheers.

Littlemews
2004-Jan-20, 05:26 AM
Usually u can find those Black Hole in a Binary Star System... but its rare
Do u think there is a black hole exist in this image?
http://antwrp.gsfc.nasa.gov/apod/image/lmcX1_rosat.gif

VanderL
2004-Jan-20, 07:03 PM
Yes, there are several of them lurking in the corners (they're not feeding so really black)
Cheers.

Pung
2004-Apr-05, 04:57 PM
'sup, guys - i'm new to the site, as was the last poster, who posed a question on whether or not white holes existed. I pose a similar, yet different question, as well as my opinion on this - do you believe that "ANTIsingularities" exist?

There is a fine line between what an anti-singularity would be, and the white hole itself, but my opinion on this is that it is very probable that they exist. Though some say that they do not (as well as white holes), because of the second law of thermordynamics. Again - do you believe they would exist?