The Colliding Galaxies of NGC 520 – September 12 2005

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Richarday
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The Colliding Galaxies of NGC 520 – September 12 2005

Post by Richarday » Fri Sep 16, 2005 10:56 am

Assuming that the hypothesis that each galaxy has a Black Hole at its centre is correct, what would happen if the two Black Holes met?

Following on from that thought, the most recent hypothesis on Matter in the Universe suggests that only ten percent of the Universes’ mass is “Visible Matter”. Could Dark Matter be the result of Matter being “processed” through Black Holes?

Empeda
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Post by Empeda » Fri Sep 16, 2005 12:13 pm

I would say unlikely - as once matters crosses the event horizon how does it get out again? But of course - nobody knows what dark matter is so we msut keep our minds open to all ideas...... :wink:
I'm an Astrophysics Graduate from Keele University, England - doesn't mean I know anything but I might be able to help!

makc
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Post by makc » Fri Sep 16, 2005 1:54 pm

when I read things like these, I think that "Dark Matter" is like "God": we can't see it, we don't know what it is, and even IF it is there at all, but, would it be there, it explains a lot of things. How valid are such concepts?

Empeda
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Post by Empeda » Fri Sep 16, 2005 2:27 pm

I've often thought that myself - but there are so many variables in the 'cosmic' theory we have at the moment that suggests there's something there, we at least have to look for it...

The primary example most people use is the spiralling of spiral galaxies. The stars at the 'edge' of the disk orbit at almost exactly the same relative velocity of the inner section - this suggests that there is lots more material that extend beyond the disk....

It is all speculative - but remember that 'dark matter' doesn't have to be bizarre or obscure - things like brown dwarfs (failed stars if you like), gases, even sticks and stones - basically anything that isn't luminous - at astronomical distances, we would see it...
I'm an Astrophysics Graduate from Keele University, England - doesn't mean I know anything but I might be able to help!