Seeing these stars is like watching a magician pulling a rabbit out of a hat. You know it happened but you don't know how it happened.

It was like pulling a rabbit out of a hat. We knew we kind of got away with one. We didn't play particularly well, but it was a great win.

The blue stars in the disk are so short-lived that it is unlikely in the long 12-billion-year history of Andromeda that such a short-lived disk would appear now. That's why we think that the mechanism that formed this disk of stars probably formed other stellar disks in the past and will trigger them again in the future. We still don't know, however, how such a disk could form in the first place. It still remains an enigma.

The blue stars in the disk are so short-lived that it is unlikely in the long 12-billion-year history of Andromeda that such a short-lived disk would appear now. We think that the mechanism that formed this disk of stars probably formed other stellar disks in the past and will trigger them again in the future. We still don't know, however, how such a disk could form in the first place. It still remains an enigma.

I'm going to have to pull a rabbit out of my hat.

The dynamics within the core of this neighboring galaxy may be more common than we think. Our own Milky Way apparently has even younger stars close to its own black hole. It seems unlikely that only the closest two big galaxies should have this odd activity. So this behavior may not be the exception but the rule. And we have found other galaxies that have a double nucleus.