A galaxy is billions of light years away how can they see it at it's current state?

Question

1 light year = 15288797334921 miles. so....a billion light years =15,288,797,334,921,000,000,000 miles. we can see that far?

Answer 1

We can't.
We actually see it as it was billions of years ago.
When you look at the sun you see it as it was 8 minutes ago; when you look at the moon, you see it as it was 1 sec ago; when you look at something 3 meters away from you, you see it as it was 10^-8 sec ago.

Answer 2

That is the wacky thing about astronomy; when you look into the night sky, you are using Mother Nature's time machine. If something is three light-years away, you are seeing it as it was three years ago; a billion light-years, a billion years ago.

As stated elsewhere, we cannot see what the present state is of anything in the night sky... even of the moon: it is one and a quarter light-seconds away.

(And of course this applies to the Sun; it is eight light-minutes away.)

We can only conjecture what the present state is of any given celestial object. The discrepancy in time is usually minimized in any reporting of something happening in the heavens as it adds an unnecessary complication. For example, a supernova is reported in the nightsky as having happened that night because of our frame of reference. Those who are familar with astronomy know that the supernove did not happen that night we saw it on Earth; it happened years or centuries before. But that is not important enough to bring up every the exact point in time; it is just understood.

Bet you didn't know we had our own time machine in the back yard night sky. We just can't use it for our own little plots... darn it!

Answer 3

confident, the education is at the back of schedule via 10 years. Planet B will disappear from A's view in 10 years. what's the use? (a million) that is exciting to do, and (2) looking out approximately planets will help us in some billion years while our photograph voltaic device will become impossible for human existence. to boot, the furthest planet we've got here across so far is 176 easy years away. that is plenty decrease than 10 MILLION easy years. just about fifty six,000 situations further. No, the age of the universe won't be able to be calculated from "this phenomenon", even if phenomenon you propose.

Answer 4

Actually, they can't see it! All they can see is what the galaxy looked like 1 billion years ago, since light takes 1b years to reach us if the galaxy is 1b light years away. For all they know, that particular galaxy might have gone bang bang long ago, it's just that the light from the explosion just hasn't reached us yet.

Answer 5

We cannot see them as they are at this moment. We see them as they were billions of years ago, because the light from them has taken that long to traverse the intervening space. Yes, we can see that far. Light continues to travel in a straight line until it is either absorbed, reflected or refracted, and when you see a star or other object, your eyes happen to be the first thing those few photons hit, not counting Earth's atmosphere. Your eyes absorb the photons, and you see the object.

Answer 6

the first thing you would have to believe is that its billions of light years away and that there seeing it in the past

Answer 7

"They" can't. If something is one billion miles away, the light "we" see from it is a product of its status one billion years ago.

Answer 8

We can only see the light from long ago coming to us through the long spaces of the universe.

Answer 9

you cannot see that far but you can see the light that left that particular galaxy x number of years ago and it(the distant galaxy) continues to emit light which we continue to see.it's very simple.

Answer 10

They can not.