what is the star furthest away from the earth that we know, of and how long has the light been traveling for? We belive

Question: what is the star furthest away from the earth that we know, of and how long has the light been traveling for? We belive that we are getting so deeper in to space that some of the light left the stars closer and closer to when the big bang occoured. Is this right. regards
- Keywords:
  Big Bang,
  light,
  star
Asked by marcusw to Adam, Catherine, Karen, Leila, Nazim on 13 Mar 2012. This question was also asked by harrysa.
- Nazim Bharmal answered on 10 Mar 2012:
  
  I think the earliest stars that have been seen from a few hundred million years after the big bang (and now is nearly 14 thousand million years after the BB). So they have been around for a long, long time. But it took a while for the first stars to ‘start up’ after the BB, so the earliest light we can see is from other objects.
- Adam Stevens answered on 10 Mar 2012:
  
  Great question – this always blows my mind, so hopefully I’ll explain it right.
  
  Light only travels at set speed (which someone else has already asked!). So light from 1 light year away takes 1 year to get us, and so on.
  
  But the universe has only been around (we think) for about 14 billion years, so light has only had 14 billion years to travel in that time.
  
  So you might think that we can only see things that are 14 billion light years away… (and this is the mind bending bit) but not quite! Because Einstein’s theory of general relativity says that space isn’t really nice and flat and cooperative, it’s a lot harder to answer this question, and we don’t really know the answer.
  
  Since the universe has been expanding since the Big Bang, lots of weird and wonderful effects will have been going on that has altered this number. A quick check says that the best answer we have is 93 billion light years ( http://en.wikipedia.org/wiki/Observable_universe ) but some people think differently.
  
  The furthest away thing we have seen is the cosmic microwave background, which is essentially the radiation left over from the Big Bang itself. This is apparently about 42 billion light years old (which doesn’t mean it came from 42 billion light years away!!).
  
  The furthest away /STAR/ we’ve seen is in the Hubble Ultra Deep Field ( http://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field ) which was made by pointing the Hubble Space Telescope at one bit of empty space for a really long time, which managed to see galaxies’ light from about 13 billion years ago.
  
  Phew. I hope that answered at least part of your question!
- Leila Battison answered on 10 Mar 2012:
  
  Because light can only travel at the speed of light (duh!), which is about 300,000 metres per second, any light we see actually left its source some time ago, and the amount of time depends on how far away the object is.
  
  Light from our sun is actually eight minutes old. When we look at the sun, we are actually looking at the sun eight minutes ago. Light from the pole star, Polaris, is 430 light years away, so we are looking at what it was doing 430 years ago, when queen Elizabeth I was on the throne!
  
  So as we look at stars further and further away, we are looking further and further back in time. If we know that the universe is nearly 14 billion years old, then you would expect that the furthest thing we would see would be 4 billion light years away. But it’s not that simple! As Adam said, there’s lots of weird wibbles and curves in what we can apparently see, so the whole picture gets kind of messed up.
  
  The furthest thing we have seen is probably a star collapsing in a galaxy about 13 billion years *agoMATOMO_URL But! Because of the curves and wibbles of space, it isn’t necessarily 13 billion light years *awayMATOMO_URL Some complicated maths puts it at 30 billion light years away.
  
  Hope that helps a bit too! The universe is so big and complicated, it can be difficult to imagine inside our tiny human heads!
- Karen Masters answered on 13 Mar 2012:
  
  The most distant light that we see is something called the Cosmic Microwave Background. It’s the first light which was released in the Universe when the first atoms formed about 400,000 years after the Big Bang. This light has traveled to use for almost the entire age of the Universe, and it’s from so far away that the distance to it depends on really small details about how we understand the Universe. The Universe has also expanded by a factor of 1000 since the light was emitted – so it’s had to travel a lot further than the distance when it was emitted!
  
  But that’s not a star. The most distant stars we know of are actually galaxies hosting supermassive black holes which are surrounded by an incredibly bright and hot disc of material which they are in the process of gobbling up. These are called quasars, and we have found some from which the light has travelled for about 14 billion years to reach us. They are actually a huge puzzle for astronomers, because they are around so soon after the Big Bang, they challenge our theories for how such things form.
  
  Great question!