Pinwheel Galaxy (M101)

Grand face-on spiral notably larger than the Milky Way, a favorite target for supernova hunters.

Core Principles & Analysis

• Its face-on orientation makes the spiral structure textbook-clear in amateur telescopes.
• It spans roughly 170,000 light-years, well over half again the Milky Way’s diameter.
• Supernovae SN 2011fe and SN 2023ixf, both first spotted here, are among the best-studied ever.

Specifications & Metrics

• GALAXY TYPE: Face-on spiral (SAB(rs)cd)
• DISTANCE: 21 million light-years
• DIAMETER: ~170,000 light-years