New Class of "Hypervelocity Stars" Discovered Escaping the Galaxy

Science_afficionado writes "Astronomers have discovered a surprising new class of 'hypervelocity stars' that are moving at more than a million miles per hour, fast enough to escape the gravitational grasp of the Milky Way galaxy. The 20 hyper stars are about the same size as the sun and, other than their extreme speed, have the same composition as the stars in the galactic disk. The big surprise is that they don't seem to come from the galaxy's center. The generally accepted mechanism for producing hypervelocity stars relies on the extreme gravitational field of the supermassive black hole that resides in the galaxy's core."

Comments

Assuming ...

[TrollstonButterbeans]

Assuming the observation gets studied and confirmed, this is probably far more common than one might initially expect.

The Milky Way has been on the move billions of years and occasionally meets up with star clusters or even dwarf galaxies.

Many of them probably settle in gravitationally, but some of them aren't going to and continue, largely, about their merry way if the relative speeds are right.

These stars could have been "acquired" 400 million years ago and it can take a long time to traverse a cross-segment of the Milky Way. And these stars would have to be smaller like our sun to have the right lifespan, and we wouldn't notice the really small ones (red dwarfs and such) because they would be hard to see so there is also a mix of observational factors in the equation.