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Stars of the Galactic Center (APOD 10 Feb 2007)

Posted: Sat Feb 10, 2007 11:46 am
by Phantom Lord
Hello, just a quick question, about how many stars are supposed to be at the galactic center? (roughly the 900 light years of the picture).
Image
Thx.

Density of Stars in Clusters and at the Galactic Center

Posted: Sat Feb 10, 2007 12:59 pm
by RJ Emery
I was wondering about the density of stars in globular clusters, like M13, or near the Milky Way's center. While the mass of individual stars has much to do with it, how close can typical stars be packed before they begin deforming and tearing at one or another?

Galactic Centre dot org

Posted: Sat Feb 10, 2007 7:59 pm
by elf master
I was so inspired by today's pic that I made a small site... I consider it easy public access to such a great view. Any time you're in the mood to see the centre of our galaxy (for a little perspective) you know where to go! :-)

http://www.galacticcentre.org

(with a slightly photoshopped swirl around the edges)

cheers,
matt

star density

Posted: Sun Feb 11, 2007 12:00 pm
by aichip
I have not calculated the needed density for star deformation, but as an example, stars in our area of the galaxy are roughly 7 light years apart on the average, where stars in the galactic core are as close as 1/4 light year on average.

This gives the results that the mean surface temperatures are significantly higher and yields slightly shorter lifespans for those stars. In globular clusters, the stars can average about 1/2 to 1 light year apart, but it depends on the cluster.

For stars to deform each other, we would have to look at tidal forces and not the actual gravitation of the stars. For a star to deform, it has to experience a differential orbital velocity from one side to the other, and since stars are typically fairly large objects, this can actually be a slight pull and still yield a fair deformation.

Since a star such as our Sun is nearly 1.4 million kilometers in diameter, another star of similar mass that is as far from it as Saturn is from the Sun might yield a slight visible deformation. However, for the really large deformations we would expect that the two would be about a hundred million kilometers or less apart. Close binaries can be a few million kilometers and we can see star material pulled into long streamers from one to the other.

So even at the galactic core, you will not see significant deformation unless it is in a binary system.

Posted: Sun Feb 11, 2007 12:31 pm
by l3p3r
I think it's great that you would put the effort in to make this site!

But I think it's also counter productive to include the swirl... the image is incredible on its own, and we don't want people to get strange ideas about what the galaxy looks like in IR!

Posted: Tue Feb 13, 2007 7:33 pm
by elf master
hi l3p3r ... glad you like, though it only took me 2 hours to make. Had one of those moments late at night. :)

I appreciate your concern with regard to the proper portrayal of Science on the Internet (regarding the image distortion) however my angle has always been to infuse astronomy with Art. (quite shamelessly in fact!) When I get some more time to work on it, I was actually planning on turbo-charging the image yet more... perhaps with a soundtrack and beams of light animating streaming from the middle (I'm a Flash animator). I feel the compulsion to help make astronomy "cool" through the liberal use of telescope imagery in multimedia projects. Consider it the theatric aspect of a galactic public awareness campaign. ;)

matt

Posted: Wed Feb 14, 2007 3:54 am
by harry
Hello All

For those who have not seen these links

The Galactic Center Radio Arc
http://antwrp.gsfc.nasa.gov/apod/ap050403.html

Galactic Center Radio Arc:
X-ray Gas Associated With Cold Gas Cloud and Galactic Center Radio Arc
http://chandra.harvard.edu/photo/2002/g ... index.html

The Galactic Centre
http://www.mpe.mpg.de/ir/GC/index.php

The Swarm
http://antwrp.gsfc.nasa.gov/apod/ap050128.html

Explosions Discovered Near Galactic Center
http://antwrp.gsfc.nasa.gov/apod/ap960228.html

======================================
I had a link that showed how close a star to star before deformation .

If I find it I will post it.

Explosions at the center of the galaxy

Posted: Tue Feb 20, 2007 5:59 am
by jimsaruff
Harry, thanks for the webpages. But, I can't get any of the further links on the Gamma Ray explosions a the center of the milky way to to come up. Any webpages that go on to talk more about this phenomena would be appreciated.

Thanks.

Great thread!

Posted: Thu Mar 13, 2008 8:44 pm
by jimsaruff
Can anyone tell me what, since 1996, has been discovered regarding 'the explosions at the center of our galaxy'?

Re: Galactic Centre dot org

Posted: Fri Mar 14, 2008 8:58 pm
by Arramon
elf master wrote:I was so inspired by today's pic that I made a small site... I consider it easy public access to such a great view. Any time you're in the mood to see the centre of our galaxy (for a little perspective) you know where to go! :-)

http://www.galacticcentre.org

(with a slightly photoshopped swirl around the edges)

cheers,
matt
woooo! *dances to the beating heart and funky tunes!*

hehehhe... nice lil' site. Maybe some links to other galactic center sites would be worthwhile to put in. =)