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View Full Version : Mass to light ratio of the Milky Way?



dakini
2006-Feb-27, 09:07 AM
Can someone please tell me what the mass to light ratio of the milky way is?

Jens
2006-Feb-27, 12:00 PM
Hmm, what's the unit?

antoniseb
2006-Feb-27, 01:30 PM
This probably wouldn't be a meaningful number unless you also got it for several other objects as well. Units don't matter much, but I kind of like ergs per gram. In these units the Sun produces about 2.

Suggested things to compare it to
- The Milky Way galaxy
- M87
- A flashlight with fresh batteries
- A globular cluster
- A supernova at peak brightness
- A low surface brightness galaxy

I'll be interested in seeing any OOM estimates to these.

Fr. Wayne
2006-Feb-27, 01:40 PM
Just recently I was reading an article about how there are billions of hidden stars barely visible with x-ray scopes still hidden. This recent information is going to take a while to re-calculate both the mass and the light known in our unique galaxy.

Peter Wilson
2006-Feb-28, 12:48 AM
I kind of like ergs per gram. In these units the Sun produces about 2.

But the OP asked in terms of mass per light, not light per mass. So I assume the answer is 0.5 (gram/erg).

antoniseb
2006-Feb-28, 12:57 AM
But the OP asked in terms of mass per light, not light per mass. So I assume the answer is 0.5 (gram/erg).
Caught me be lazy again.