Messier 109 (M109)

Barred spiral beside Ursa Major's bowl, prototype of the class and host of a 1956 supernova.

Core Principles & Analysis

• Its central bar channels gas inward to a ring of star formation.
• Méchain discovered it in 1781; like M108 it waited until 1953 for its Messier number.
• It heads a small group of several dozen galaxies.

Specifications & Metrics

• GALAXY TYPE: Barred spiral (SBbc)
• DISTANCE: ~55 million light-years