M101: Spiral Galaxy (Ursa Major) RA: 14h 03.2m / DEC: +54° 20'.9 Instrument: 10-inch Starfinder |
M101 is a relatively easy star hop from Mizar and Alcor, the naked eye double star at the bend of the Big Dipper's handle. The galaxy is about 6.5 degrees due east from the pair. A string of 4th through 8th magnitude stars leads the way. However, getting to the right field is only half the challenge. M101 is deceptively hard to see. It has an integrated visual magnitude of 7.9, which might lead one to conclude this is an easy object to detect. However, that glow is spread over an area almost as large as the Moon. M101 is a low surface brightness object, just 23.8 magnitude per square arc second. M101 will be hard to detect if your skies are even moderately light-polluted. |
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