# The Naked Scientists Forum

### Author Topic: sending a spacecraft through a black hole!  (Read 3438 times)

#### paul.fr

• Guest
##### sending a spacecraft through a black hole!
« on: 22/05/2007 01:13:12 »
If we were to send a spacecraft or probe through a black hole, what would happen? If the craft was equipped with, a camera, sent back continuous radio signals and an infra red beam would we be able to pick up all of those signals once it entered the black hole?

If not how far in to, or close to the black hole would it get before we stopped reveiving the signals?

#### another_someone

• Guest
##### sending a spacecraft through a black hole!
« Reply #1 on: 22/05/2007 02:08:55 »
If we were to send a spacecraft or probe through a black hole, what would happen? If the craft was equipped with, a camera, sent back continuous radio signals and an infra red beam would we be able to pick up all of those signals once it entered the black hole?

If by "entered the black hole" you mean pass through the event horizon of a black hole, the very nature of an event horizon is that once through, nothing, but nothing (with the paradoxical exception of gravity) can leave.  Thus, no radio, no infra red, nothing, but nothing, can return from the spacecraft to where you are outside of the event horizon (otherwise, it would not be an event horizon).

If not how far in to, or close to the black hole would it get before we stopped reveiving the signals?

The event horizon is the event horizon, and that defines where signals stop leaving the black hole.

What I am not sure of is whether teh size of the event horizon remains constant as one approaches the black hole, or whether, the closer one gets to the black hole, the smaller the event horizon will get.

Ofcourse, Ian will tell you about all the complications that occur with a spinning black hole.
« Last Edit: 22/05/2007 02:29:12 by another_someone »

#### paul.fr

• Guest
##### sending a spacecraft through a black hole!
« Reply #2 on: 22/05/2007 02:13:29 »
If by "entered the black hole" you mean pass through the event horizon of a black hole, the very nature of an event horizon is that once through, nothing, but nothing (with the paradoxical exception of gravity) can leave.  Thus, no radio, no infra red, nothing, but nothing, can return from the spacecraft to where you are outside of the event horizon (otherwise, it would not be an event horizon).

George, i wrote that topic because i thought you may be bored. Then you scupper it with one answer! [xx(]

What if there was another spacecraft - say a twin - on the edge of the black hole, could that act as a relay...straws, clutching at.

#### another_someone

• Guest
##### sending a spacecraft through a black hole!
« Reply #3 on: 22/05/2007 02:33:24 »
If by "entered the black hole" you mean pass through the event horizon of a black hole, the very nature of an event horizon is that once through, nothing, but nothing (with the paradoxical exception of gravity) can leave.  Thus, no radio, no infra red, nothing, but nothing, can return from the spacecraft to where you are outside of the event horizon (otherwise, it would not be an event horizon).

George, i wrote that topic because i thought you may be bored. Then you scupper it with one answer! [xx(]

Sorry, and I was editing it while you were answering  [:I]

What if there was another spacecraft - say a twin - on the edge of the black hole, could that act as a relay...straws, clutching at.

Not a get out.  The problem is that a signal from within the black hole will take an infinite time to get out of the black hole.  If you have a relay of spacecraft, it will still take a very lonmg time to get from one spacecraft to the next, and the cumulative time to get all the way will still require an infinite time.

#### Supercryptid

• Hero Member
• Posts: 606
##### sending a spacecraft through a black hole!
« Reply #4 on: 22/05/2007 12:49:52 »
I wonder. If we were to find a way to artificially create gravitational waves/radiation, could that be used as a signaling method by a spacecraft within a black hole? Can gravitational waves escape a blackhole's event horizon?

#### another_someone

• Guest
##### sending a spacecraft through a black hole!
« Reply #5 on: 22/05/2007 13:04:44 »
I wonder. If we were to find a way to artificially create gravitational waves/radiation, could that be used as a signaling method by a spacecraft within a black hole? Can gravitational waves escape a blackhole's event horizon?

This was something I was wondering; but an analogous question is whether electric charge (as distinct from electromagnetic waves) can leave a black hole.  Whether there is a difference in how Black Holes treat waves from how they treat static fields?

#### The Naked Scientists Forum

##### sending a spacecraft through a black hole!
« Reply #5 on: 22/05/2007 13:04:44 »