Messier 62 is known for being one of the most irregularly shaped globular clusters in our galaxy. This might be because it is one of the closest globular clusters to the center of our galaxy and is affected by galactic tidal forces, displacing many of the cluster’s stars toward the southeast.
|Visible From Pacific Northwest||April To August|
|Best Time To Observe||June and July|
|Minimum Size Of Viewing Device||Small Telescopes|
|Object Type||Globular Star Cluster|
|Designations||Messier 62, M62, NGC 6626, GCl 51, C 1658-300, MWSC 2512|
|Right Ascension||17h 01m 12.60s|
|Number Of Stars||150,000|
|Object Radius||49 light years|
|Distance From Earth||22,200 light years|
Messier 62 is one of Charles Messier’s original discoveries. The comet hunter found the cluster on June 7, 1771, but did not take its accurate position until June 4, 1779.
William Herschel was the first to resolve the globular cluster into individual stars using a 20-foot telescope in 1785. He described M62 as “extremely bright, round, very gradually brighter in the middle, easily resolvable, about 4′ in diameter. With 240 and strong attention I see the stars of it. It is a miniature of the 3rd of the Connoiss. [Messier 3]”
John Herschel catalogued the cluster as h 3661 in August 1834 and later added it to the General Catalogue as GC 4261. He noted, “Remarkable; globular cluster; very bright; large; gradually much brighter toward the middle; well resolved; stars from 14th to 16th magnitude.”
In 2013, a team of researchers discovered a black hole in M62. Designated M62-VLA1, the object was classified as a stellar mass black hole, the kind that forms from the collapse of a massive star. This was the first black hole ever found in a globular cluster in the Milky Way.
Locating M62 In The Sky
The cluster is relatively easy to find because it lies 7.5 degrees southeast of Antares, the brightest star in Scorpius constellation and 16th brightest star in the sky.
The cluster can also be located using Wei, Epsilon Scorpii, a fainter star just to the southeast of Antares. M62 lies 4.75 degrees northeast of the star.
Messier 62 appears as a small hazy patch in binoculars, while small telescopes reveal a comet-like shape. The cluster’s stars can only be resolved in larger instruments, starting with 8-inch telescopes, which begin to resolve the cluster’s outer regions. The best time of year to observe M62 is during the summer. The cluster can be a tricky target for northern observers as it never rises very high above the southern horizon.
Globular clusters are honestly low hanging fruit if you have a quality refractor Short exposures are the best option for globular clusters for imaging as short exposures will not saturate the star cores and it is far easier to preserve the star colors both in the cluster itself and in the surrounding sky.
Imaging M62 can be done with a smaller telescopes such as 6 inch telescopes. There are great astrobin and cloudy nights articles that can provide great tips as there are a plethora of forum posts but not necessarily a plethora of blogs too provide assistance.
Sources And Further Reading
Descriptions of all of Messier Objects can be found here.