For no reason at all, it just explodes and all life as we know it is over, any chance of that?
From what we know about stellar physics and evolution, no, there isn’t.
Not being a smartass, but why not? I’ve always wondered about this. Also, while I’m here, if someone can explain to me this as well:
How does the sun burn with no oxygen in space?
We understand a lot, or think we do, about the evolution of stars. Our star can’t go nova without wandering way off the mainstream sequence.
That’s what the KRYPTONIANS said!!!
To emphasize silenus’ point, saying that the sun “burns” is misleading, because our normal use of the word “burn” is in the chemical sense (e.g., wood on fire), whereas the Sun converts hydrogen into helium by nuclear fusion, which is a physical process and is completely different than chemical burning.
-Tofer
Because it’s in an equilibrium between temperature and gravity. The particles that make up the Sun are hot- they want to expand outward. But gravity pulls them inward. The Sun isn’t undergoing any rapid changes in size (we’d notice if it were), so it must be in equilibrium.
The nuclear fusion at the Sun’s core is going at a rate that is determined by the temperature of the Sun’s core (it goes as T[sup]4[/sup], IIRC). For it to go any faster, you’d have to increase the temperature of the core of the Sun. I can’t think of anything that could do that, other than something really unlikely like a collision with another star. I certainly can’t think of anything that could do that without our noticing it a long time before it happened- you’d have to have something fairly massive (at least as massive as Jupiter, probably much more) at a temperature of at least 15 million degrees go into the core of the Sun. We’d notice if something like that happened. It’s very unlikely that anything like that would happen- you’d need a collision with another star, and those almost never happen, even when galaxies collide. The stars in galaxies are just too far apart.
The Sun’s core can’t just spontaneously heat up, because heat is energy and energy is conserved. It can’t just draw the energy to heat up its core in from space, because that would violate the Second Law of Thermodynamics- heat normally flows from a hot body to a cold body, not the other way around (if you want to make heat flow from cold to hot, you have to use energy to do it, which is how a refrigerator or air conditioner works).
When the Sun runs out of hydrogen fuel, in 5 billion years or so, the fusion reactions in the core will slow down (all the helium will be getting in the way of the hydrogen nuclei that want to fuse). That will make the Sun contract, which will heat up the core until it is eventually hot enough to fuse helium. Helium fusion will generate a higher temperature than hydrogen fusion does, so then the Sun will expand into what’s called a red giant.
We know that the Sun isn’t about to run out of hydrogen any sooner than 5 billion years or so, because we have models of the Sun that, with some nuclear physics, tell us how much hydrogen the Sun has available to fuse, and we know from observation how much energy the Sun puts out. Our theory of how planets form (and some planetary systems in the process of forming that we’ve observed) tells us that the planets formed about the same time as the Sun did. We have samples of rocks that tell us that the planets are about 5 billion years old, so we infer the age of the Sun from that.
It’s not actually burning- it’s using nuclear fusion to convert hydrogen into helium. It’s sometimes called “hydrogen burning”, but it’s not the same thing at all as something burning because it’s combining with oxygen. It’s similar to burning in that fuel (hydrogen) gets used up, and it produces energy, but it doesn’t require the presence of oxygen.
There is one way for the Sun to explode in a very short period of time, discussed in the November 2002 issue of Scientific American in an article entitled “When Stars Collide.”
The article is summarized here:
From the linked excerpt:
So I guess you had already covered that…
Here’s a cool artist’s impression, though, picturing what the Sun’s final moments might look like:
If you want to make it a little less noticeable (before the Earth-shattering kaboom, of course), you could have the collider be a black hole, instead. The effects would be much the same in the end as from a white dwarf, but unless you knew exactly what to look for, you wouldn’t see it coming.
And I think we’d see even a white dwarf coming in, before it hit the Sun.
ISTR reading somewhere that someone did a study and calculated, even in the collision of the Andromeda galaxy and the Milky Way (which is going to happen, eventually) that fewer than 10 collisions between stars would happen. With 10[sup]11[/sup] stars in the galaxy, that means odds of 1 in 10 billion that a stellar collision would happen while two galaxies were colliding.
You might see some gravitational effects, though. Sending an object that’s a solar mass or so flying through the solar system is going to have some effects. (There are also the same arguments about the likelihood of a black hole colliding with the Sun as there are about a star colliding with the Sun)
YE CANNA CHANGE THE LAWS O’ PHYSICS, MAN!
I realize you probably mean. The sun explodes…poof and is gone! Us and everything with it. But in reality the sun is exploding constantly. Huge exposions with solar flares that present a real threat to life on earth are very possible at any time and without warning. So yes, the sun could actually explode enough to kill all life on earth at any time without cause or forewarning. Sorry folks but that’s the truth. Didn’t mean to burst your bubble… 
nothing’s safe is it?
And they were right since their sun didn’t explode.
:rolleyes:
Their sun is still there, fanboy. Whether or not the planet would explode was not part of their calculations.
If the sun in fact produced a solar flare large enough to kill us, how long would it take? In other words, if some scientist saw this killer “flare”(or whatever it would be called) in a giant telescope , how long before complete destruction? Ten minutes? Instantly?
It’s possible. The next question should be: how likely is it?
There’s no particular reason to think the sun is more active now than it was in the past. Obviously, it hasn’t flared up enough in the past to kill off all life on earth in the billion years or so that we have a fossil record of, so it’s very unlikely that it will suddenly do so within the lifetime of anyone living.
The question then becomes: has it flared up enough to kill off a lot of plants/animals/what have you, but not enough to kill off all life on earth? If it did, it would almost certainly cause a mass extinction event. There’s debate on the average time between mass extinctions, but it’s generally agreed to be on the order of tens of millions of years. Assuming that all of those mass extinctions are caused by massive solar flares (unlikely, but gives us a useful upper limit on how likely a flare like that is), that would mean that they only happen every 10-100 million years on average. So it’s maybe possible but not at all likely that one will happen tomorrow.
I hope I get this right…
The laws of probability/Chance dictate that you can determine, based upon the number of known occurances to number of chances the likely outcome… since the Sun hasn’t exploded yet, the chances are then astronimically high against it ever happening.
however, the corrolary to that is that the longer you go without a probable event occuring, the closer you get to the time it will occur (lasvegian statistics)… therefore, we are getting closer and closer to the time it will happen.
In short, might, might not… wanna bet?
How would the person betting on it happening collect on his bet if he “wins”?