I saw a really cool paper (to me) on the pre-print server today. Astronomers Kuzic et al. have made detailed measurements of two groups objects in the center of the galaxy within half a parsec of the center of the Milky Way. These objects, named IRS 13E and IRS 13N (aren’t those exciting names?) are each composed of very young stars (less then 1 million years). The objects in 13E are Wolf-Rayet and O-Type giant stars that will quickly blow themselves out and the stars in 13N are still embedded in dust and gas.
This paper caught my attention for one simple, stupid reason. Every read Ringworld by Niven? It depicts a bunch of stars all going Nova at once in the center of the galaxy. Well, O-stars that are sufficiently large enough can do just that!
The physics here is also pretty amazing. The supermassive black hole in the center of the Milky Way is ~4×10^6 Solar Masses. This means its event horizon is ~200,000 AU from the center of the galaxy. Around this massive compact object there are pockets of mind boggling star formation. It appears that the Milky Way’s bar may be in part to blame – 13E appears to be embedded in the bar and 13N is in or near it. Nevertheless, we hadn’t thought this type of star formation is possible. It was thought that stars in the galactic center had formed in waves 7 million and 100 million years ago. Now, we thin we know better, and we think that can (in cosmic terms) still be forming today.
And someday, someone may look to the center and see a Ring World like Galactic Center supernova.
High res version of the image above at http://www.nrl.navy.mil/NewsRoom/images/galctr.jpg
Pamela,
the best thing about astronomy is the endless surprises it provides. This is another good one. Keep the surprises flowing.
John
Is it possible that the center of our galaxy would contain a 4 millions solar masses huge ” proto star ” emitting IR, whose cooling time would be large with respect to the age of Universe, instead giant black hole ? A pro to star that will never ignite, and was formed at the begining of the galaxy ?
J.P.Petit ( senior researcher, astrophysicist, retired, France )