Black Holes are soooooo cool!!

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Black Holes are soooooo cool!!
Black Hole Caught in an Eclipse By Ker Than
Staff Writer
posted: 12 April 2007
01:28 pm ET

A recently observed black hole eclipse is giving astronomers a chance to test key predictions about the swirling disk of material that surrounds it.

Astronomers spotted a cloud of interstellar gas as it passed directly in front of NGC 1365, a galaxy located 60 million light-years away that contains a supermassive black hole at its center.

Scientists think the supermassive black hole, also called an active galactic nucleus, or AGN, is fed by a steady stream of material swirling around it in the form of a so-called accretion disk.

Black holes can't be seen, because matter and light that enter them do not come out. Astronomers detect them by noting their gravitational effects on surrounding material. AGNs are even more difficult to study because they are enshrouded by thick shrouds of glowing gas and dust.

Even more challenging, the accretion disk of NGC 1365 is too small for astronomers to resolve directly with a telescope. But the eclipse allowed astronomers to estimate its size by measuring how long its X-ray radiation was blocked by the passing cloud.

Using NASA’s Chandra X-ray Observatory, researchers observed NGC 1365 six times over a course of two weeks in April 2006. During five of the observations, high energy X-rays generated by swirling material in the accretion disk was visible. However, in the second observation—which corresponded to the eclipse—no radiation could be detected.

“For years, we’ve been struggling to confirm the size of this X-ray structure,” said study team member Guido Risaliti of the Harvard-Smithsonian Center for Astrophysics (CfA) and the Italian Institute of Astronomy (INAF). “This serendipitous eclipse enabled us to make this breakthrough.”

Size estimate

The researchers now think the black hole’s accretion disk is about seven AU in diameter. One AU is equal to the distance between the Sun and Earth. This suggests the disk is about 2 billion times smaller than NGC 1365 itself, and only about 10 times larger than the estimated size of the black hole’s event horizon, the sphere inside which everything is trapped. The finding is consistent with theoretical predictions.

The eclipsing cloud that passed in front of NGC 1365 was located one-hundredth of a light-year from the black hole’s event horizon.

“Thanks to this eclipse, we were able to probe much closer to the edge of this black hole than anyone has been able to before,” said study team member Martin Elvis, also of CfA. “Material this close in will likely cross the event horizon and disappear from the universe in about a hundred years, a blink of an eye in cosmic terms.”


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Or black holes?

Or black holes?


Hambydammit
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I so rarely comment on

I so rarely comment on stuff like this, but I admit, black holes are way cool.

This is cheezy, but do you remember the movie, The Black Hole?  Awful disney movie from maybe the late 70s, where the mad scientist had a spaceship just beyond the event horizon, and he was going to go into it to try to live forever, or something like that.

Anyway, I was a kid, and thought black holes were very neat, so I read as much as I could get my hands on, which wasn't all that much in those days.

Later, I read Steven Hawking, and it took me two or three weeks to pull myself out of a near-catatonic state while my brain unwrapped itself out of an eleven-dimensional pretzel.  I try not to do that to myself anymore, but I watch every show on the Science Channel!

 

Atheism isn't a lot like religion at all. Unless by "religion" you mean "not religion". --Ciarin

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American Atheist
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Black holes are cool. I've

Black holes are cool.

I've always wanted to see a black hole suck in another black hole. 


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Hambydammit wrote: This is

Hambydammit wrote:
This is cheezy, but do you remember the movie, The Black Hole? Awful disney movie from maybe the late 70s, where the mad scientist had a spaceship just beyond the event horizon, and he was going to go into it to try to live forever, or something like that.

I remember that movie, it was horribly corny. LOL.

I am like you when it comes to black holes, they are immensly fascinating. I contemplate the singularity, event horizon and nature of black holes like theists contemplate god, with one difference, we can actually infer the black holes existance with observable data.