Courtesy of EarthSky
A Clear Voice for Science
www.EarthSky.org ^[1]

^[2]

Fuzzy star cluster looks like a comet

A reader wrote, On November 4, I went to study the constellation Orion, but first I had to see the star Sirius and there was a glimmer below Sirius and upon looking it seemed to be a very nice comet. Has anyone else seen this? I am a newby … (and) would like someone to verify if they see this. I am quite up and excited. It wasn’t a comet, but very likely was a lovely star cluster called M41 ^[3]. So the identification with a comet was wrong, but it is a reasonable mistake. The nuclei of comets look like fuzzy patches, much like M41 in a small telescope.

The confusion with a comet and this cluster is not a new one. In the late 1700s, Charles Messier ^[4] gave this object the number 41 on his list of “objects to avoid.” He was a comet hunter who wanted others to realize that this object, which looks like a comet, really isn’t.

There are over 100 of the so-called ‘Messier objects’ or “M-objects” known today. Today’s amateur astronomers consider them among the most prized objects to be viewed through binoculars and small telescopes. Here’s a list of M-objects ^[5]. Advanced amateurs can observe them all, and can earn a Messier certificate ^[6] from the Astronomical League.

Written by Larry Sessions