Astrophysics (Index)About

ring galaxy

(ring-like galaxy, darker in the middle)

A ring galaxy is a ring-shaped galaxy, with much or most of its brightness within a relatively-narrow ring some distance from the center. The ring's typical bluish color indicates bright, necessarily-young stars, suggesting a young age for the galaxy.

There is still discussion about their formation: they might result from galaxy interaction (galaxy merger or tidal interaction between passing galaxies) or from gas collisions in a manner to trigger star formation in the a ring shape.

(galaxy type)
Further reading:

Referenced by pages:
Hoag's Object