M63: The Sunflower Galaxy (APOD 17 Apr 2008)

astrolabe · Post by **astrolabe** » Fri Apr 18, 2008 2:44 am

This beautiful island universe has a very large dust lane in the forefront, and the galaxy itself doesnt appear to be as symetrical as say M104 (the Sombrero Galaxy). I've often wondered about a galaxy's influence on another galaxy in that one may lose matter to another.

I would have thought that a structure's core would be sufficiently powerful enough to hold on to it's surrounding material and, along with it's halo of dark matter, succeed in resisting the pulling off of it's matter by the gravity well of another galaxy. Stronger black hole perhaps? More mass in the outer arms of the usurper? And lastly, once the process of losing material begins,would centrifical forces play more significant role?

Regards to all.

bystander · Post by **bystander** » Fri Apr 18, 2008 12:57 pm

http://antwrp.gsfc.nasa.gov/apod/ap080417.html

I like the 3d appearance of the image, like water down a drain. In the tug-of-war between galaxies, the one with the most mass (not necessarily visible, may be dark matter) usually wins, acquiring yet more mass. I think it's the overall mass of the galaxy that counts, not just the central region.

http://antwrp.gsfc.nasa.gov/apod/ap000627.html

orin stepanek · Post by **orin stepanek** » Fri Apr 18, 2008 1:02 pm

http://apod.nasa.gov/apod/ap080417.html
It is difficult to see any nearby galaxy unless U8313 is close enough. it looks to be more in the distance though. I don't know if it is really losing it's material; but it is rather stretched out.

Orin

iamlucky13 · Post by **iamlucky13** » Fri Apr 18, 2008 11:45 pm

I think this galaxy looks much more like a carnation (if you count the faint outer arms) than a sunflower.

Astrolabe...when a galaxy is by itself, Gravity is balanced with inertia. As another large mass approaches however, that balance changes. Stuff has to move. Depending how large and close, it may simply tug stars into more elliptical orbits, it may disrupt galaxies into long tidal streams, or galaxies may steal large amounts of stars and gas from each other.

astrolabe · Post by **astrolabe** » Sat Apr 19, 2008 12:11 am

Hello iamlucky13,

Yes, that's good. I can see it now and it makes a great deal of sense. Thanks. By the way, the quote at the bottom of your posts has always made me smile!

Along with your answer I would imagine that size can make a difference as well. For instance the one I mentioned (M104) at 50,000 ly across is about half the size of M63.

harry · Post by **harry** » Sat Apr 19, 2008 5:15 am

Hello all

I was just looking for a site to explain m63 form.

Small Wonders: Canes Venatici
http://www.cloudynights.com/documents/swcanes.pdf

Galaxies - Ursa Major and surroundings
http://www.ngc7000.org/ccd/gal-ursamajor.html

Deep Sky Objects: Galaxies
http://www.davesastro.co.uk/dso/galaxies.html

http://www.spacegazer.com/september-2004-g.asp

Messier Observing Projects
http://www.ast.cam.ac.uk/~ipswich/Obser ... ojects.htm

iamlucky13 · Post by **iamlucky13** » Sat Apr 19, 2008 6:10 pm

astrolabe wrote:Along with your answer I would imagine that size can make a difference as well. For instance the one I mentioned (M104) at 50,000 ly across is about half the size of M63.

You bet. The larger galaxy might exert enough pull on the smaller one to yank stars completely out of orbit, while the smaller one is only swinging stars in larger galaxy into more elliptical orbits, as an example of one possible outcome.