What we see in the sky is history?

When we are talking about "thousands, millions light years" away,
the stars/galaxy that we see in the telescope,
are they history?

 

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In stead of "history" their light is a picture not very detailed of the distant past there, but it is detailed enough to be quite confident that the physic governing structures (as reflected in energy levels of atoms and large collections there of, called galaxies) back then and there, was like it is here and now. That is not saying that the universe is static - only that its changes seem to be controlled by the same natural laws we know. I. e. Those laws seem to be static. Assuming that is true, then we have been able to write the history of the universe for last about 13 billion years and predict its future at least that far into the future.

 

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Yes, many of those stars that telescopes see are now dead but the light from them is only now being seen here on Earth.

 

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Every time we look at the Sun, we are seeing it as it was 8.25 minutes ago....
We look at Alpha Centauri, and we are seeing it as it was 4.5 years ago....
We look at M31 and we are seeing it as it was 2.5 million years ago.
So yeah, it's history.

 

History, mystery, majesty!

 

how about black hole?

 

What about a black hole?

 

Could it also be that we cannot see stars farther than 13.8 billion light years away because past that point nothing existed?

 

Older than 13.8 billion years, but yes....

Those objects are about 46.6 billion light years away.

 

so we are future.

 

to the stars perspective we are their past, the light from us has reached them and they have seen our death.

 

wow.
nothingness - Big Bang - History - Earth - Life - Precious

 

what do you mean by saying "Light from us". yes we will be dead when sun light reach those far stars.

 

The Observable Universe is around 46 billion L/years radius.
You have neglected spacetime expansion.
Beyond that point, the Universe certainly exists, but is causally disconnected from us due to the expansion rate exceeding or equaling light.

 

Not really. From M31's perspective, we are 2.5 million years in the past.

There is no Universal now.

 

M31 is 2.5 mly away from us....

So today of us, will be seen by M31 after 2.5 mly...So technically our present is M31's future as will be seen to them after 2.5 mly. So when an observer at M31 sees our light of now after 2.5 mly then we will be his past. As of now M31 has no means to see our present. They are seeing Paranthropous, if at all they could see light from Earth.

 

A galaxy which we see 13.8 Billions light years ago,
at this moment, what is it exact location?
Should be more than 13.8B, right?

 

As we said: 46 billion ly.

 

The best estimate of the age of the universe as of 2013 is 13.798 ± 0.037billion years but due to the expansion of space humans are observing objects that were originally much closer but are now considerably farther away (as defined in terms of cosmological proper distance, which is equal to the comoving distance at the present time) than a static 13.8 billion light-years distance.It is estimated that the diameter of the observable universe is about 28 billion parsecs (93 billion light-years), putting the edge of the observable universe at about 46–47 billion light-years away.

https://www.google.com/url?sa=t&rct...zoCgDw&usg=AFQjCNE8c1P5g4L771McmHrDjbT7Xi65TQ

 

What is the "force" or "pressure" to expand the universe (like a balloon) , every movement need kinetic energy, from where the universe gets the energy to do this "work"?