Black Holes with an Appetite
SDSS J142005.59+530036.7 from AEGIS
This object has the imaginative name SDSS J142005.59+530036.7. It lurks in the Bootes constellation and although it looks like a star, it’s actually a Quasar 15.3 billion light years away from earth going by its redshift. I have a love for Quasars, so I couldn’t resist this one in Budgieye’s OOTD posted on the 6th of July!
In the heart of this galaxy lies a super massive black hole like most other galaxies. This particular one is an AGN, an Active Galactic Nucleus. AGN are super massive black holes in the centres of galaxies that are pulling in material from around them such as stars and gas. This material gets pulled into a ring doughnut shaped accretion disk around the black hole, and as this material swirls round it causes friction, releasing radiation out into the galaxy. The centres of these galaxies can be so energetic that they can outshine the galaxy itself; hence all you can see in the picture above is a star-like object- the nucleus of the galaxy.
This energy can also be concentrated into jets of high energy plasma racing out at near to the speed of light for thousands of light years from the poles of the black hole, and depending on how these jets are positioned in relation to us the galaxy the AGN is lurking in can be called radio galaxies, Blazars, Seyferts and so on. In this case it’s a Quasar, so the jet is positioned so that it’s not quite beaming directly at us. Here’s a great OOTD by Fluffyporcupine on AGN!
And thanks to Alice for helping me out! 🙂
10 responses to “Black Holes with an Appetite”
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- - July 9, 2010
Galaxy Zoo 
Very little help, only the odd suggestion about full stops and remembering the link to Fluffy’s OOTD! It is well worth browsing a lot of old ones . . .
Fabulous OOTD Budgieye (as were the others!) and lovely post, Stellar 🙂
Great and interesting post, Stellar ! Good on you.
JKHC.
Great post.
Although I am a little confused. When you say it is 15.3 billion light years, I thought that the universe was about 13.7 billion light years old, so isn’t that further than light has had time to travel or is that figure the distance it would be away from us by now. Hope that makes sense.
Wayne
Nice one, stellar. Well done!
Hi Wayne
You’ve hit the problem of living in an expanding Universe! The object is 15.3 billion light-years away today, but of course the light reaching us know wouldn’t have had to travel that far. It would have completed most of its journey when the Universe was much smaller than it is today. The light travel time is in fact about 9 billion years, so we see this galaxy as it was almost 4 billion years after the Big Bang. Hope that helps…
Great post Stellar :D:D
Chris: I’m really confused, now. I thought I had a good grasp of galactic distances but you’ve just put that all in doubt. Are you saying the distances given for distant objects isn’t the true distance or isn’t the distance really traveled by light? Do you have a link to something I can read that will help explain further what you’ve just explained to Wayne?
Distances, in cosmology, can be very confusing.
Not only is there the fact that the universe is expanding, and light has a finite speed, but the very concept of distance in General Relativity – which all contemporary cosmology is based on – is not simple … there’s comoving distance, luminosity distance, angular diameter distance, …
Here is a good, comprehensive, explanation: http://nedwww.ipac.caltech.edu/level5/Hogg/Hogg_contents.html
And here is an shorter, simpler one: http://www.mpifr-bonn.mpg.de/staff/hvoss/Cosmology/index.html
It’d be great if some options for “possible black hole” and “exploding galaxy” could be added into the classification interactions. I ran across a huge burst just a little bit ago when classifying while on break and had no recourse but to classify it as “other”.