· If the Universe is only 14 billion years old, why isn't the most distant object we can see 7 billion light

Question

years away'?

Answer 1

Put it this way: 5 billion years ago, light is emitted from a star. It sets out on its journey to Earth.

It then arrives here, and we see the star as it was five billion years ago. But the universe has expanded, so the distance has increeased. That way, the star is further away from us. A side effect of this is apparent faster-than-light motion of distant galaxies. This is an optical illusion, predicted long before it was ever observed.

Answer 2

OK, I've looked at the other answers. Here's a different slant. We CAN see back to within 500million years of the big bang but no further. Because of reasons beyond your question we can't see beyond this. The 'microwave background' [google Penzias and Wilson] is the echo of the 500million year old point. The point is that this is MICROWAVE radiation and not visible radiation. It's microwave because the billions of degrees of temperature has cooled down as the universe has expanded. The heat has become spread out in the last 13.5billion years [14 billion - 500 million] The reason we cannot SEE further than 7 billion light years is because the further something is the more it gets 'redshifted'. [look it up on google] Beyond 7 billion LY objects get redshifted to the point where they no longer are visible to the human eye. They can still be detected by radio and microwave telescopes though. Hope that helps

Answer 3

You are thinking incorrectly about the Big Bang. You are thinking that it was an explosion that happened somewhere, flinging galaxies into the void. Wrong.

According to the Big Bang model, the universe is, and always has been homogeneous. The entire universe is uniformly filled with galaxies and there was never an explosion, and there is no void space into which the galaxies are streaming. What the BBT says is that the space between the galaxies is stretching. Imagine a very big raisin bread rising in the oven, and you're an ant astronomer sitting on one of the raisins. No matter which raisin you're on, you see raisins in every direction everywhere, all moving away from you. But the raisins aren't going anywhere, leaving tracks through the bread; it's the bread that is rising between them.

Same thing in the universe (except that the universe has no boundaries like the raisin bread has). The galaxies aren't going anywhere; space is expanding between them. So A galaxy 40 billion light years away didn't have to "get there from here." It started there; it's just that "there" wasn't as far away 13 billion years ago.

Answer 4

Two possibilities spring to mind:

1. If the universe was a sphere 14 billion ly in diameter, only at the centre would the most distant object be 7bn ly away. If the observer is 2 ly from the centre, then an observer would be able to see 2 ly to the centre plus 7 ly beyond. making a total of 9 ly. Conversely, that observer would only be able to see objects up to 5 ly in the opposite direction.
Bear in mind that we do not know that the universe is spherical - it may be some other shape which would permit more distant observations.

2. Although Einstein's writing suggested that the speed of light was an absolute speed limit for things within the universe, it is thought that this rule does not apply to the fabric from which it is made. So, after the big bang took place, nothing WITHIN the universe moved faster than light speed, but the universe itself - or parts of it - actually expanded at a much faster rate. This has resulted in a universe with dimensions much larger than would have been possible otherwise.

Answer 5

How far away is the most distant object.

One possible answer is we are not at the dead centre of the universe.

Another is that in those 14 billion years the universe has slowly expanded, which given light has a defined speed, probably gives problems to working out what the universe actually looks like.

Answer 6

Likely the universe has a maximum size of about 6 billion light years in radius.
Any visible objects beyond this do not exist today.
Since everything in the universe began in the same spot,anything you see had to go to where you see it then emit electro magnetic radiation and you would wait for 6 billion years to be able to see it.
Although the universe has a maximum radius of about 6 billion light years,it could be much older.
As long as the pulse that initiated the universe continues the universe will continue in packets of 6 billion light years in radius,when the pulse stops the universe will go out of existence in 6 billion years.

Answer 7

You are wrong, about 10years ago The Hubble space telescope was randomly pointed into the universe, the spot that it looked at would be the equivalent to us of looking at a penny 1 mile away. The photographs that came back showed hundreds of galaxies we knew nothing of. We have only ever seen about 2% of the entire universe.
1,000 yeras ago we only knew of the stars e could see with the naked eye. 1,000 years from now we will see alot more than we could ever imagine today. Science isn`t fixed....