theastrophysicist

Spiral Galaxy Animation

Did you know that stars routinely enter and leave the spiral arms of the galaxy? In fact, the motion of the stars might even be in the opposite direction from what one might guess by the shape of the spiral!

The spiral arms are just regions where greater densities of stars are found. In turn, when gas enters the spiral arms, they get compressed, allowing newer, brighter, younger stars to form (presumably shown with the red blips in the animation).

I have a minor complaint though… If I were the author of the animation, I would flip the colour scheme so that brighter younger stars show up bluer.

Reminds me of traffic density waves…