Is There a Reason for the Unique Shape of This Galaxy?

[Tyger]

It's a galaxy in the form of a torus and the gas, dust and star forming regions lie on the surface of the torus.

http://hyperphoto.photoloft.com/view/exportImage.asp?s=cano&i=10620506&w=640&h=800

 

[RuroumiKenshin]

I think it is really fascinating! I thought a taurus was a bull?
Why is it shaped the way it is?

 

[HazZy]

a torus is a bulge or large swell. it is very weird though.

 

[marcus]

Originally posted by Tyger
It's a galaxy in the form of a torus and the gas, dust and star forming regions lie on the surface of the torus.

http://hyperphoto.photoloft.com/view/exportImage.asp?s=cano&i=10620506&w=640&h=800

Hoag's object is a ring galaxy---several examples of ring galaxies are known----there is another in the picture

blob of old (reddish) stars in the middle
a ring of young blue stars---and star formation

one theory is it used to be a barred spiral and something
knocked the bar out

There is a ring galaxy called Cartwheel which has evidence of its center having been crashed thru by another small galaxy which is visible leaving the scene and is already 250,000 LY away.

There's a theory that a collision at the center could cause an expanding ripple of star formation out like a rock going thru the surface of a pond.

 

[drag]

Greetings !

Yeah, I've seen it some time ago in the news.
Can't remember if they said why does it look
like that, but I suppose that statisticly if you
look at enough galaxies you'd expect one to
look like that. Anyway, what's that in the middle ?
A quasar ? Just some star that was in the way ?
Also, it's not exactly a torus because the
matter seems evenly ditributed, not in a curved
empty cylindrical form.

Live long and prosper.

 

[enigma]

Originally posted by HazZy
a torus is a bulge or large swell. it is very weird though.

A torus is actually like a donut.

 

[HazZy]

oh well, i was using the definition of a torus in anatomy, thought they would be the same.

 

[kyle_soule]

Originally posted by drag
Greetings !

Yeah, I've seen it some time ago in the news.
Can't remember if they said why does it look
like that, but I suppose that statisticly if you
look at enough galaxies you'd expect one to
look like that. [blue]Anyway, what's that in the middle ?
A quasar ? Just some star that was in the way ?
Also, it's not exactly a torus because the
matter seems evenly ditributed, not in a curved
empty cylindrical form.?[/blue]

The yellow nucleus is just a bunch of older stars. The best explanation of the formation is a galaxy passed nearby, stripping it somewhat.

Cartwheel galaxy-
http://ftp.seds.org/pub/images/hst/Cartwheel.jpg

Another picture of Hoag Object, more realistic of what a person would see, I thought it was interesting-
http://www.geocities.com/benoit_schillings/hoag.jpg