Star explosions

of all the time we put into observing stars, has anyone ever documented seeing one go out?
Maybe an explosion that happened millions of years ago that we can just see now because of the time it takes for the light to reach us. Anybody got any info?

Here is a link by space.com that has what you want to know.www.space.com...

wait, so in 10000-60000 years that Eta Carinae is estimated to explode, its gonna take out earth too? would the explosion from 7500 light years away really have an impact on us? the one in the 1800's didnt. Or would the supernova wipe us out because of the black hole? any info?

I think it is too far away for it to effect earth, but I think what they were saying by "if anyone is still around to watch it" is that it should exploded in 10,000 to 20,000 years. They may think people will be dead then.

Originally posted by Hemps
wait, so in 10000-60000 years that Eta Carinae is estimated to explode, its gonna take out earth too? would the explosion from 7500 light years away really have an impact on us? the one in the 1800's didnt. Or would the supernova wipe us out because of the black hole? any info?

No, it would not have any signifigant effect on earth.

It will go nova, not black hole, there is a big difference.

And even if it did go black hole it still wouldn't effect us, as a hole that small would evaporate pretty fast.

7500 light years is 6,400,000,000,000 miles if my math was correct. Thats a pretty long distance even for gravity let alone a stelar explosion.

alrighty. good explanations. deathdragon, thanks for clearing that up, i completely missed that point.

scienceguy, can you explain the whole black hole thing to me, i never really understood it.

No problem Hemps, if you need any more info on space and thing in space (except life in space) I know one or two things about it.

well, since scienceguy hasnt replied yet, you wanna take a crack at explaining the whole black hole thing to me?
i've heard theories of them being worm holes, and just anti-gravity, but what's yur take on it?

Ok lets see, A black hole is what remains when a massive star dies. As the star dies, the nuclear fusion reactions stop because the fuel for these reactions gets burned up. At the same time, the star's gravity pulls material inward and compresses the core. As the core compresses, it heats up and eventually creates a supernova explosion in which the material and radiation blasts out into space. What remains is the highly compressed, and extremely massive,
core. The core's gravity is so strong that even light cannot escape.


To find out much more click on this link science.howstuffworks.com...

You will be able to read it much faster then i can type.

There is a really good book it talks about this and much more, it is a really deep book. It is called the "The Elegant Universe". If you can get this book. or watch it on the web here www.pbs.org...

oh i get it now, so its not even a hole, its just gravity so strong it evens pulls in light, and that makes the appearance of a hole.
cuz even the black matter is a source of light, but the gravity is so strong it pulls that into it too so that they can even exist as times runs on.

It still hard to visualize the whole concepet, but what i have read its like a vacume hose, So i think its som what of a hole. They also say that at the end of the black hole is a white hole, but one has never been seen so its just a theory.


It way help also too to watch those videos I posted to another site. It will tell you how gravity works or how they think it works. it hard to explain.

[Edited on 12-24-03 by deathdragon]

i dunno if i like that whol vacume thing cuz it makes it sound like the matter is going somewhere, i think that a black whole is just pulling in light at such a high rate it shows the appearance of darkness, or a hole, you know what i mean?

I find it hard to believe that matter can disappear.

Yes I understand what you when. Light gets sucked in so fast it can't shine out to see the hole. Also you could be right about the vacuum thing because it just still a theory.

Oh, sorry hemp, got distracted by Groom Lake photos.

Just to add a lil more the the black hole question...

Its a point where gravity become so great, and matter so dense, it implodes space-time. You'll sometime hear a black hole reffered to as a singularity. Thats because it is a point where space time has been collapsed by gravity down to a single dimention, or a singularity.

It was mathematicly predicted by relativity.

Wormholes are still just a theory however. Wormholes are theoretical tears in space-time. They make for great Sci-fi but have very little support in reality.

If wormholes do exist, we should be able to make them using high energy devices. Currently we don;t have any devices that high energy, though if you could power up a capacitor enough that would rip open space time according to theory.

To help me understand Black Holes more:

What would happen if earth orbited into a black hole?

I would think it would tear earth apart into particals

Originally posted by Zodiac
To help me understand Black Holes more:

What would happen if earth orbited into a black hole?

The earth and everything on it would be crushed down to basic subatomic particles, and maybe even smaller as it fell into the hole. As for the matter, its doesn't dissappear, it just get crushed down to a single point in space. Black hole have masses related directly to how much matter falls into them. Small hole then evaporate off due to hawking radiation, and the large ones tend to be more stable and feed off surrounding matter.

Its a tough concept, but its all there, just pressed into a single point of existance. To my knowledge there is no physics yet to descripe matter in that state.

from what ive taken from the other posts, the world would be sucked into gravity so harsh, earth would collapse into a dimension with no space/tiime, so we would cease to exist anymore

Originally posted by Zodiac
To help me understand Black Holes more:

What would happen if earth orbited into a black hole?

If you want to get real fun with the idea of YOU falling into a black hole, then its more than just getting crushed.

The gravity would do some wacky things.

For example, if you fell in feet first, then you head would be moving faster through time then your feet. Also you'd be streached to thousands of miles long as you fell. Of course to you it would only seem like a instant then you'd be dead, but watching you fall from a safe distance would be quite a sight.