What is the biggest star we know of?

[vincentm]

Is it Antares? That is a huge star. Also how does it get to be so big and how long till it goes supernova or is it going to go supernova?

 

[Labguy]

Is it Antares? That is a huge star. Also how does it get to be so big and how long till it goes supernova or is it going to go supernova?

I think, without knowing if any POP III stars are actually "observed", that the http://www.solstation.com/x-objects/pistol.htm" is thought to be the largest.

 

[vincentm]

Thanks labguy, those pics are amazing.

 

[Chronos]

Eta Carinae, estimated at 100-120 solar masses, is the most massive star in our neck of the woods. It is very unstable and could go supernova at any time. At 8000 light years, it would probably not be a threat to life on earth, but would put on a fabulous show, being easily visible in the daytime. http://www.seds.org/messier/xtra/ngc/etacar.html

The most massive star in our galaxy is probably either the Pistol star [as labguy noted] or the less famous LBV1806-20 located about 45,000 light-years from earth. Both are estimated to be around 150 solar masses.
http://www.cnn.com/2004/TECH/space/01/06/stellar.giant.ap/
Only Pop III stars, theorized to have formed when the universe had hardly any metallicity, are believed capable of being much larger than this. Pop III's may have been as large as 1000 solar masses, although none have actually been observed.