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How long will it take for us to realize that the universe exploded

let's say an explosion happens 1 billion light years way from earth. Since nothing is faster than the speed of light and we see stars in the night sky as they were millions of years ago, Will it take millions of years for the explosion to reach us? Even though the universe exploded millions of years ago? and we see it millions of years after the explosion.

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Your Q is worded to allow 2 possibilities, so you should learn to ask a well defined Q. However, if the WHOLE universe, for some nutty reason, exploded beyond the Big Bang explosion that we are already in, we'd die, OK? No observations after that.
If ONLY an explosion billions of light years away happened, as this Q hints at, it would take billions of years to reach us at the speed of light.

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Hi Freed ! It's me !! Another fun answer-thanks!!!
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Sincerity, if the ones asking the Qs appreciated my answers as much as you, I'd answer more. No kidding - if not for your last rate up I was going to leave these ingrates in their ignorance! OK, they get one more chance thanks to you.
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We would explode probably in the next few days because we are in the universe.

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well if the universe exploded i think we would explode too cause were part of the universe the reason why we still see light from stars that no longer exist is because they are billions of light years away from our galaxy however our galaxy is one of many in the universe so if the universe explodes we explode that very second as well=)

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I don't think we'd vet find out because if the universe exploded so would we.

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I'm not sure what you mean by "the universe exploded". The scenario you describe is for an explosion IN the universe. Those happen all the time: supernovae, GRBs, etc. and yes, it would take the signal a billion years to get to us. For a billon years we would not know there was an explosion.

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Since we cannot detect anything traveling faster than light, an explosion 1 billion light years away, would mean that it would take the light from that explosion 1 billion years to reach us. Allowing for the fact that the universe is also expanding, means that the trip would take slightly longer than 1 billion years. That is talking about an explosion within our universe, and this is quite common. We see explosions that happened from even more distant locations.
If your asking about the entire universe exploding all at once, which includes the earth, distance is not a factor. The whole universe exploded. Bam, we're gone.

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