Low surface brightness galaxy

Most LSBs are dwarf galaxies, and most of their baryonic matter is in the form of neutral gaseous hydrogen, rather than stars.

[2][3] Rotation curve measurements indicate an extremely high mass-to-light ratio, meaning that stars and luminous gas contribute only very little to the overall mass balance of an LSB.

The centers of LSBs show no large overdensities in stars, unlike e.g. the bulges of normal spiral galaxies.

In their past, they had fewer tidal interactions or mergers with other galaxies, which could have triggered enhanced star formation.

[5][6] UGC 1382 was previously thought to be an elliptical galaxy, but low-brightness spiral arms were later detected.