I just had a thought. If the universe is 15 billion years old... how could we see stuff thats past those 15 billion?

Well years and light years are completely seperates measures of things. Years is a measure of time and light years is a measure of distance. So even though the universe is 15 billion years old it could easily be hundreds of light years big and therfore we can see things 30 ,50, 200 billion lightyears away!!

When you say how could we see stuff thats past those 15 billion? do you mean how can we see further than 15 billion light years or how can we see things at are older than 15 billion years?

Sorry but your topic heading and then the actual question in the thread are two different things and I`m not sure what you are asking!!!

I`m probably no help at all , but I`m just posting what I thought and I hope you understand what I`m trying to say otherwise sorry for posting something quite wrong and irrelevant to what you wanted to know!!!

Well, I mean, think about it. If the universe is 15 billion years old... then something 100 billion light years away would have had insufficient time to reach us, wouldnt it?

When you look up at the stars, what you must understand is that they actually do not exist.

The light from those suns takes hundreds of millions of years to get to our planet, which is what you are seeing. SO by the time that light reaches us, the sun is actually long dead and the solar system it supported is also long dead and doesn't exist.

Therefore, when you look up at the stars, you are seeing light from suns which died hundreds of millions of years ago.

Didn't see your last post there.

How do we know that the universe is only 15 billion years old? I believe it is infinitely old, not beginning or end.

I'm not sure I understand the question.
If you mean how far can we see literaly, then I don't know.
I know you cannot see Pluto with the naked eye, so thats
probably the limit. Actually, if Pluto was bigger than Jupiter, then
maybe we would.
If you're asking how we see stuff 100 billion lightyears from now,
then I'd say the earth would not exist anymore.

I'm not sure about the date but I see your point.

The only way we could see more light years away than our universe is old would be if it was beyond the area included in the big bang and was part way to us before the big bang.

The only way we could see farther is if the universe is older.

No idea..


But if you think about it, the images we see of space and stars (from hubble, and whatnot) are from light that's traveled millions/billions of light years.

So some stars we see now, have since gone Nova, New stars have been born, galaxies have moved countless lightyears.. But we won't know until the LIGHT reaches earth.

So IMHO, what we see now is not what is really there.

i have heard that some of the nearest stars are only 32 lightyears away or something. the sun is supposed to explode in the year 100000000 or something close to that and the sun is way smaller then most of the stars out there so wouldnt most of the stars be still in tact?

32 light years?

The end of our solar system is further away than that. Try 32,000 maybe.

That depends on where you consider the edge of the solar system to be but Asterix is right it's much closer than 32 light years away.

Pluto averages about 40 AU away, so 40 x 8 minutes means Pluto is 5.3 light hours away from the sun.

I think we can all agree there's a big difference between 32 years and five hours.

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