This is not just an 18th magnitude dot. This 'dot' has a red shift of 3.21. That means it is currently 21.6 billion light years away, but it appears in our past 11.7 billion light years away. That's totally messed up when you can't even say how far away it is. It takes far away things to another level. It is a Quasar, a galaxy with a central super massive black hole jet pointing straight at us. I can't express how bright this thing is other than to say that it has an absolute magnitude of -30.0. OK, well I'll have a go. Hang on, I'll get my calculator out... If the quasar was at a distance of, say, the Pleiades star cluster is from Earth, it would appear nine times brighter than the Sun is to us on Earth (caveat: that's probably not an appropriate distance for the calculation). Our universe is only 13.7 billion years old and you're looking back across most of that time, to a time when not only the Earth didn't exist, but the Sun also didn't even exist!
Monday, 23 January 2012
Quasar madness.
This is not just an 18th magnitude dot. This 'dot' has a red shift of 3.21. That means it is currently 21.6 billion light years away, but it appears in our past 11.7 billion light years away. That's totally messed up when you can't even say how far away it is. It takes far away things to another level. It is a Quasar, a galaxy with a central super massive black hole jet pointing straight at us. I can't express how bright this thing is other than to say that it has an absolute magnitude of -30.0. OK, well I'll have a go. Hang on, I'll get my calculator out... If the quasar was at a distance of, say, the Pleiades star cluster is from Earth, it would appear nine times brighter than the Sun is to us on Earth (caveat: that's probably not an appropriate distance for the calculation). Our universe is only 13.7 billion years old and you're looking back across most of that time, to a time when not only the Earth didn't exist, but the Sun also didn't even exist!
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