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CthulhuBob
2003-May-29, 09:39 PM
Hello everyone,
I'm new to the board and the site but after spending a couple days reading through it I couldn't help myself any longer and decided to contribute. :lol: I should also point out I am a layman (a well-read layman but a layman nonetheless, hehe).
I was trying to explain the concept of black holes to my 8 and 10 year olds when I realized that they may have seen some of it on TV in one of the weirdest places.
Back in the early '90's there was a cartoon known as Ren n' Stimpy. It is lower-than-low-brow but before John Kricfalusi (the series creator) was fired by Nickelodeon it was very very funny. In any case, there was an episode from that time (appropriately named) Black Hole. In this ep our "heroes" fall into a black hole and end up in another dimension. Now in the beginning of the episode they show their wind-up spaceship falling into the BH.
The exact sequence has the ship speeding toward the BH then grind to a halt, foreshorten, then pop out of existence. Now if memory serves, I read a couple different articles that stated this is exactly how it would appear to an outside observer watching an object vanish into a BH. Heck, they even show Ren and Stimpy experiencing tidal forces and stretching out!
What I was wondering is if anyone else could confirm that this is correct or am I completely confused?

P.S. I do realize the whole alternate dimension story after these events is horse-pucky so please don't flame me over the rest of the ep :D .

tracer
2003-May-29, 10:07 PM
Close -- gravitational time dilation would cause the spacecraft to appear to hover right at the brink of the Event Horizon for all eternity.

Of course, long before that point, the tidal forces would become so intense that the spacecraft and all its contents would be ripped apart into a single spaghetti-like string of atoms. (Unless the black hole was really really big, such as the black hole at the center of a galaxy.)

CthulhuBob
2003-May-29, 10:13 PM
Close -- gravitational time dilation would cause the spacecraft to appear to hover right at the brink of the Event Horizon for all eternity.

I knew I forgot something. Darn time dilation! The scary thing is that a cartoon this ridiculous would even be this close.


Of course, long before that point, the tidal forces would become so intense that the spacecraft and all its contents would be ripped apart into a single spaghetti-like string of atoms. (Unless the black hole was really really big, such as the black hole at the center of a galaxy.)

I don't think they mentioned whether it was a stellar or galactic BH so lets give them the benefit of the doubt (hehe).

Donnie B.
2003-May-29, 10:54 PM
In addition to time dilation (and hence "hovering" at the event horizon), the gravity well would cause the ship to appear to redden, eventually out of the visible range -- so it would fade from view.

CthulhuBob
2003-May-29, 10:59 PM
In addition to time dilation (and hence "hovering" at the event horizon), the gravity well would cause the ship to appear to redden, eventually out of the visible range -- so it would fade from view.

Hmmmm, can't remember if the ship changed colour. Will watch it again tonight to be sure.
But would it appear to an outside observer to foreshorten as well? No one mentioned that yet so I hope it at least got that right. :)

tracer
2003-May-30, 12:51 AM
Of course it would foreshorten. By the time it was right at the brink of the event horizon, it would have accelerated to near-light-speed, so it'll be subject to special-relativistic as well as general-relativistic effects. ;)

Odinoneeye
2003-May-31, 11:24 AM
All I learned from that episode was that if you are going to enter a black hole, always be sure to have correct change for the bus ride home. That and always be sure your ice cream bar is not, I repeat NOT, a bar of soap.