Cosmoview Episode 46: Gemini North Spies Ultra-Faint Fossil Galaxy Discovered on Outskirts of Andromeda

An unusual ultra-faint dwarf galaxy has been discovered on the outer fringes of the Andromeda Galaxy thanks to the sharp eyes of an amateur astronomer examining archival data processed by NSF NOIRLab’s Community Science and Data Center. Follow-up by professional astronomers using the International Gemini Observatory, a Program of NSF NOIRLab, revealed that the dwarf galaxy — Pegasus V — contains very few heavier elements and is likely to be a fossil of the first galaxies.