Messier 100 (M100)

One of the brightest spirals of the Virgo Cluster, a calibration yardstick for the cosmic distance scale.

Core Principles & Analysis

• Hubble Space Telescope observations of its Cepheid variables anchored the measure of the Hubble constant.
• Five supernovae have been recorded in it since 1901.
• Two faint outer arms make it grander than most Virgo spirals.

Specifications & Metrics

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