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Peggy
05-20-2007, 11:19 PM
If you fall in there's no way to get out, but you might stretch your survival time a bit.

http://www.nature.com/news/2007/070514/full/070514-21.html

A common idea in physics is that you shouldn't try to blast your way out of there. Black holes, it's said, are like the popular view of quicksand: the harder you struggle, the worse things become.

But Geraint Lewis and Juliana Kwan of the University of Sydney in Australia say this is a myth. Their analysis of the problem, soon to be published in the Proceedings of the Astronomical Society of Australia1 (http://www.nature.com/news/2007/070514/full/070514-21.html#B1), shows that in general your best bet is indeed to turn on the rocket's engine. You'll never escape, but you'll live a little longer.

Angelinity
05-20-2007, 11:22 PM
If you fall in there's no way to get out, but you might stretch your survival time a bit.

http://www.nature.com/news/2007/070514/full/070514-21.html

go with flow, i say, see where it takes you... or what used to be you...

blacbird
05-21-2007, 02:13 AM
In terms of pure factual practicality, you'd be long gone well before you got anywhere near the event horizon of a black hole. The accretion disks of black holes generate godawful amounts of x-rays, far beyond what any remotely possible technology could shield.

caw

Peggy
05-21-2007, 04:40 AM
I don't know. If we are able to develop the technology to fly to the galactic center, we may figure out a way to shield ourselves from the x-rays too.

benbradley
05-21-2007, 05:28 AM
In terms of pure factual practicality, you'd be long gone well before you got anywhere near the event horizon of a black hole. The accretion disks of black holes generate godawful amounts of x-rays, far beyond what any remotely possible technology could shield.

caw
This is certainly true for the common black hole of a few solar masses, especially with a companion that provides lots of infalling matter. Is this also true for the superlarge Galactic-core black holes? The gravitational gradient isn't nearly so great (so much so that people and "reasonable" spaceships could survive being near and going through the event horizon), and it seems bits of matter near each other would be orbiting the black hole at nearly the same speeds, due to the much larger scale of things. Of course anything that falls in at a different angle would be another story. The high density of stars in the Galactic core could be a problem too.

dclary
05-23-2007, 01:05 AM
Don't you need a little robot with Roddy McDowell's voice, too?

Peggy
05-24-2007, 04:41 AM
Don't you need a little robot with Roddy McDowell's voice, too? or Slim Pickens

MargueriteMing
11-11-2007, 03:04 PM
This is certainly true for the common black hole of a few solar masses, especially with a companion that provides lots of infalling matter. Is this also true for the superlarge Galactic-core black holes? The gravitational gradient isn't nearly so great (so much so that people and "reasonable" spaceships could survive being near and going through the event horizon), and it seems bits of matter near each other would be orbiting the black hole at nearly the same speeds, due to the much larger scale of things. Of course anything that falls in at a different angle would be another story. The high density of stars in the Galactic core could be a problem too.

As you get closer to a large body the gravitational force gets stronger. The event horizon by definition is the place where you must exceed the speed of light to get out again. Since in theory this can't be done, you can't get out, no way, no how.

Bartholomew
11-12-2007, 12:01 AM
I'd be interested to know if the event horizon of a Black Hole forms a more or less perfect sphere, or whether or not you can get closer to the anomaly by approaching it from a certain direction.

(Assuming all the other problems could be dealt with.)

benbradley
11-12-2007, 12:04 AM
As you get closer to a large body the gravitational force gets stronger. The event horizon by definition is the place where you must exceed the speed of light to get out again. Since in theory this can't be done, you can't get out, no way, no how.

The question isn't how to get out, it's how to survive in.:wag:

benbradley
11-12-2007, 12:08 AM
I'd be interested to know if the event horizon of a Black Hole forms a more or less perfect sphere, or whether or not you can get closer to the anomaly by approaching it from a certain direction.

(Assuming all the other problems could be dealt with.)

If the black hole is rotating, the event horizon won't be a sphere.

oscuridad
11-12-2007, 12:48 AM
as I recall the rotating ones are the really interesting ones, I can;t exactly remember why, though. Anyone remember?

blacbird
11-12-2007, 02:36 AM
It is a near-certainty that all black holes rotate, and real fast, too.

caw