Talk about double-whammy. Why does it always have to be me?
Don’t ask me how I know, I just do. How long have we got? It takes something like six minutes for sunlight to reach us, so will everything look and feel alright till then? How long after the fireworks start will the blast take to hit us? Will anyone get a chance to hear the original explosion before they are vaporised? Could we ride the wave out to the next star?
I’m gonna throw caution to the wind and order the pizza right now. I know it’s risky but hell, that’s the kinda guy I am. I like it crispy anyway.
I am looking forward to seeing responses to the questions here. IF the sun were to explode, how long would it take for us to realize it? Would there be direct damage, or more long-term damage (freezing to death, loss of crops, etc.)?
The sun is about 8 light minutes from earth. According to well accepted physics theory, no information can travel faster than the speed of light, so it would be impossible to even know the sun had expolded until this was visible. As for hearing the explosion, you won’t. Sound cannot travel through the vacuum of space. It is possible that the sun’s explosion coul ddo somethign to the earth’s atmosphere like boil it off into space. You then might hear some sounds on the night side of the earth.
Anything that happens at the Sun, it will take us at least 8 minutes to find out. But it’s generally accepted that stars that are about to explode will give advance warnings of some sort a lot more than 8 minutes ahead of time. And, in fact, some of those things that’ll happen before it explodes will probably be enough to fry us all by themselves. For instance, towards the end of its life, a star like the Sun is expected to swell up to much greater size, likely enough to engulf the Earth. But according to all of the standard models for such things, we’ve got another few billion years before it’ll happen to the Sun.
Among other concerns, an immediate effect would be the instantaneous nonexistence of the sun’s gravity, resulting in all the planets flying out into interstellar space. And it’s cold out there.
It’s eight minutes, but yes, assuming that the sun was just going along as normal and suddenly up and exploded. If there were some visible sign that something was different about the sun before it exploded, we’d see that eight minutes before it happened.
Probably depends on the exact nature of the explosion. We can’t really extrapolate from any known astronomical phenomena, because as far as we know stars like our sun just don’t suddenly explode.
No, sound doesn’t travel through space. There might be sound from material from the sun hitting the atmosphere, but IANA Atmospheric Physicist, so I have no idea if anyone could hear that before they were vaporized.
If you assume the sun just suddenly disappeared into another dimension or there were a really violent explosion that hurled all of the matter in the sun out of the solar system, then yes. In every stellar explosion that we know about, though, a substantial amount of the mass of the star in question stays where the star was before the explosion (in supernovae, this creates a white dwarf, neutron star, or black hole supernova remnant).
So is it agreed then that gravity works at the speed of light? Something about that is troubling to me but, being an English major, I have no idea what it is. Is the sun expected to blow at the speed of light? Cuz if it doesn’t, the next question is: how far away can we get from the sun once our orbital bond is broken before the asplosion catches up to us? And would we necessarily notice any reduction in solar gravity since the mass of the sun isn’t changing, just it’s density?
I’m pretty sure you’re joking, but I’ll address this in case anyone is taking you seriously.
Gravitation is a property of matter, and the matter that makes up the sun would still exist (most of it, anyway), so the gravitation would remain until the sun’s mass spread out past Earth’s orbit. After it’s spread that far, Earth would mostly only feel the gravity of the mass that remains inside its orbit (assuming the spread is in a uniform sphere). But the mass that passed the orbit would have destroyed whatever’s left of the planet on its way to the interstellar void anyway.
And gravitational effects travel at the same speed as electromagnetic effects. Any change in the Sun’s gravity would also take 8 minutes to be felt on Earth. This is one of the major predictions of Einstein’s General Theory of Relativity, and it’s held up to many experiments and observations.
It’s not instantaneous. To the best of our knowledge, gravity propagates at the speed c, the same as light. Even if the sun suddenly disappeared by some bizarre act of God, you still wouldn’t know about it for about eight minutes. So still no need to cancel that extra cheese.
Also as an aside this may sound stupid but, when a rocket fires in space does it not have to push against something to make it go forward?
Oh I just thought of a better one. My space-ship is going down so I man the life-raft and I have to chuckle to myself when I realise I am sitting in an actual rowing-boat like the ones down on earth (someone’s going to get fired over this). I don’t know if this is someones idea of a prank or what but I am floating in the empty vacuum of space.
I start rowing, my technique is awesome, the oars flatten out on the backstroke and everything. But am I moving?
I just found a copy of it recently, meself.