Cont..If a nuclear warhead doesn't... How does a supernova do it?

Question

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I've been taught in school, that stars regularly turn supernova, that this is a common event for stars after being around in space for so long. Also I've been told our sun will come to a point where it will turn supernova aswell, and will likely destroy the earth within the wake of this cosmic event. This suggests to me that a force unfathomable to me will be propelled from the sun, colliding with the earth, busting it to bits, or throttling us out of the orbit we used to have with our now, non existant sun. (granted we need the sun but would earth REALLY blow up?)

I would like to know of the destructive capabilities of a supernova, also the repricussions it will have on a planet nearby. Sorry for using 2 posts for 1 question, i just want to be specific Thank you for your replies, Its appreciated

Answer 1

The sun is a regular main sequence star with a lifespan believed to be around 9 billion years.
Its believed that it has already 4.5 billion years on its odometer, so it would do another 4.5 billion years from now on.
So most likely you will not see anything else in your life than the sun as you know it.
When the sun has burned all its current fuel it uses, the balance of gravity and inner pressure starts changing. And a very complex but well understood process starts within the sun.
I'm afraid i'm unable to go into the details, but the story what we would observe would be that it first turns into a red giant star having its outer layers about the orbit of mars and is cooler than right now, (but even not cool enough not to turn the earth into a globby piece of magma).
Sometimes later the fuel for the red-giant-phase will be burned and again the gravity/pressure ratio will have a dramatic change.

Its believed that at this time the outer shells where ejected into space in a class II nova and the sun turns into a white dwarf with higher temperatures than right now.
the ejected matter than would be a planetary nebular like M57 for example --> http://www.nightskyinfo.com/planetary_nebulae/m57.jpg
cute end, i think
stars in general do have different histories, and what happens is much depending on how much mass they have, how fast they rotate, and which fuel they burn. this process is (as earlier stated) well understood since we already observed the skies and found enough examples, along with our knowledge how fusion theoretically works.

since all this happens in some billion years i would not worry too much, and if you ask me.. thinking how mankind is wiped off this planet by such events does not make much sense knowing this when this happens

Answer 2

From Wikipedia: The Sun does not have enough mass to explode as a supernova. Instead, in 4-5 billion years, it will enter a red giant phase, its outer layers expanding as the hydrogen fuel in the core is consumed and the core contracts and heats up. Helium fusion will begin when the core temperature reaches about 3×108 K. While it is likely that the expansion of the outer layers of the Sun will reach the current position of Earth's orbit, recent research suggests that mass lost from the Sun earlier in its red giant phase will cause the Earth's orbit to move further out, preventing it from being engulfed. However, Earth's water and most of the atmosphere will be boiled away.

Answer 3

A supernova would destroy any nearby planets, but as was stated, out sun does not have enough mass to go supenova. but don't sweat the end of our sun in 5 billion years or so, worry more about the Andromeda galaxy colliding with ours in about 3 billion years.

Answer 4

And to answer this...

You say you've been taught that the sun will supernova and blow up the earth?

Well, first, the sun will increase it's size dramatically becoming what's known as a red giant. It will grow so large that it will "swallow" the earth. Earth will be LONG gone before our sun reachs the point of a supernova.

Answer 5

Your on the right trace the thing about a sun going super nova is that the gravitational forces around the sun exceed it's own limits, so the sun dose not explode it, collapse on it's self. If you where to witness this event you would not only see the black hole but time it self would slow down the closer you go to the event horizon, on top of that the gravitational forces would rip you apart one molecule at a time for a very long time, before you actually got sucked in to the black hole it's self, the other thing to remember is that the tidal forces that the super nova would give of would probably be enough to throw us out of orbit, which in turn would cause us to spin out of control. The point is if a super nova dose go of and you see it shot your self it will be a lot quicker and a lot less painless.