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meteor
Jul25-03, 05:50 PM
J1148+5251 is the most distant object known, is a quasar and has a redshift of z=6.41. In its core lies the most massive black hole known, a moster of 3 billion solar masses. Now, astronomers have discovered that the first stars of this quasars started to form 650 million years after Big Bang
www.newscientist.com/news/news.jsp?id=ns99993974

marcus
Jul25-03, 06:24 PM
Originally posted by meteor
J1148+5251 is the most distant object known, is a quasar and has a redshift of z=6.41. In its core lies the most massive black hole known, a moster of 3 billion solar masses. Now, astronomers have discovered that the first stars of this quasars started to form 650 million years after Big Bang
www.newscientist.com/news/news.jsp?id=ns99993974

Exciting news, especially about the carbon and oxygen-containing gas cloud around the hole---evidence of a prior generation of stars during the brief 870 million years since time zero.

I plugged your figure of z = 6.41 into Ned Wright's Cosmic Calculator
http://www.astro.ucla.edu/~wright/CosmoCalc.html
and it told me that we see the quasar at a time 870 million years after zero,
and that the light travel time was 12.8 billion years,
and that the present distance to the quasar is 28 billion light years.

meteor
Jul25-03, 06:40 PM
I've done a quick search and have found that this quasar is situated in the constellation of Ursa Major

marcus
Jul25-03, 06:54 PM
Originally posted by meteor
I've done a quick search and have found that this quasar is situated in the constellation of Ursa Major

Bravo and thanks, meteor,
it is a pleasure to have a rough idea where important things in are in the sky
I will think of it tonight if I see the Great Bear


At Ned Wright's cosmology tutorial he has news of a quasar
with z = 6.4 posted since about November 2002. The astronomer reporting the quasar was Bob Becker. It could be the same quasar? What is new, in the report you linked us to, is the carbon/oxygen containing cloud of gas----evidence of earlier stars? Or is the quasar itself a recent find?

meteor
Jul25-03, 07:33 PM
Is the same quasar. I knew of it from time ago, but when it was announced they didn't gave a name for it . Now I'm glad to at least knowing what name it has
The second most distant object known is the quasar J1030+0524, with a redshift z=6.28, and situated in the constellation of Sextans

marcus
Jul25-03, 09:43 PM
Originally posted by meteor
Is the same quasar. I knew of it from time ago, but when it was announced they didn't gave a name for it . Now I'm glad to at least knowing what name it has
The second most distant object known is the quasar J1030+0524, with a redshift z=6.28, and situated in the constellation of Sextans

It would seem that the name J1148+5251
tells the position in the the sky
11 hours 48 minutes RA and +52 degrees
which is indeed in Ursa Major

There is also a star with a jupiter-size planet
in that constellation as I recall
so it has several associations
besides the main one with bears

edit: that direction to that quasar is marked by the star gammaUMa which is the one below where the handle joins onto
the dipper