UT: Andromeda's Double Nucleus – Explained at Last?

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UT: Andromeda's Double Nucleus – Explained at Last?

Post by bystander » Mon Apr 05, 2010 1:12 pm

Andromeda's Double Nucleus – Explained at Last?
Universe Today - 2010 April 04
In 1993, the Hubble Space Telescope snapped a close-up of the nucleus of the Andromeda galaxy, M31, and found that it is double.

In the 15+ years since, dozens of papers have been written about it, with titles like The stellar population of the decoupled nucleus in M 31, Accretion Processes in the Nucleus of M31, and The Origin of the Young Stars in the Nucleus of M31.

And now there's a paper which seems, at last, to explain the observations; the cause is, apparently, a complex interplay of gravity, angular momentum, and star formation.
The Nuclear Stellar Disk in Andromeda: A Fossil from the Era of Black Hole Growth http://asterisk.apod.com/vie ... 31&t=18582