Looking Up: Messier's Mistake

Jun 26, 2017

Charles Messier, French astronomer, at the age of 40
Credit wikipedia

This week on Looking Up we learn the whereabouts of Messier's missing galaxy.

All June we’ve been talking about cool galaxies that are part of the Virgo Super-Cluster, and are visible in Southern Colorado skies right now. Let’s keep up that theme for this last June episode, but let’s add a twist, seemingly taken from the pages of a TV crime drama – the Missing Galaxy of Messier! 

One remarkable night in 1781, Charles Messier recorded the locations of not one, not two, but eight fuzzy nebulous objects near each other in the summer sky. But for one of those objects, M 91, Messier recorded the location incorrectly! Over the years, astronomers looked at the location Messier had specified and found – nothing! It wasn’t until 1969 that an amateur astronomer in Texas figured out Messier’s mistake. It turns out, Messier had recorded the location of M 91 relative to M 58, but in fact, he had actually measured from M 89, a completely different galaxy. Using this corrected location, M 91 was no longer missing and observers could now find this lovely face on barred spiral galaxy, nearly 60 million ly from Earth, as it speeds away at just under 1 million miles per hour. Talk about a fast getaway!

If you’d like to take a closer look at the missing galaxy or any of the wonderful and amazing things in the sky, please visit csastro.org for a link to information on our monthly meetings and our free public star parties! 

This is Hal Bidlack for the Colorado Springs Astronomical Society, telling you to keep looking up, Southern Colorado!