Messier 93 (M93)

Also Known as: NGC 2447

Object Type: Open Cluster

Constellation: Puppis

Distance from Earth: 3,380 light years

Apparent Magnitude: 6.0

Coordinates: RA 07H 44M 30.0S DEC -23deg 51min 24sec

Actual Size: 20 to 25 light years in diameter

Apparent Dimensions: 22 arc-minutes

Discovered by: M93 is one of Charles Messier’s original discoveries.
The French astronomer found it on March 20, 1781 and subsequently added it to his catalogue of comet-like objects.
He described his 93rd entry as a “cluster of small stars, without nebulosity, between the Greater Dog [Canis Major] and the prow of the ship [Puppis of Argo Navis]".
The ship Messier was referring to is Argo Navis, represented by the Greek constellation Argo Navis, which has since been divided into three smaller ones – Vela, Puppis and Carina – each representing a part of the ship: the sails, the stern, and the keel and hull.
Caroline Herschel, the younger sister of William Herschel, independently discovered it in 1783, thinking it had not yet been catalogued by Messier.

Description: M93 is an open cluster in the modestly southern constellation Puppis, the imagined poop deck of the legendary Argo.
The cluster contains about 80 confirmed members and there are probably hundreds more.
The brightest stars in M93 are type B9 blue giants. The cluster also contains at least three red giants.
The estimated age of the cluster is 100 million years.
Messier 93 has a Trumpler classification I,3,r, which means that it is detached from the surrounding star field with strong central concentration (I), it contains bright and faint stars (3), and is richly populated (r).
M93 has a great spatial radius of 5 light-years, a tidal radius of 13.1±2.3 light years, and a core radius of 4.2 light years.
Its age is estimated at 387.3 million years.
It is nearly on the galactic plane and has an orbit that varies between 28,000–29,000 light years from the Galactic Center over a period of 242.7±7.9 million years.
Fifty-four variable stars have been found in M93.

Click Below Image(s) for Full Size:

Messier 93 is not very hard to find as it is located in the same area of the sky as Sirius, the brightest star in the sky.
M93 can be seen without binoculars under exceptionally clear, dark skies, and is easy to find with binoculars. It has an apparent magnitude of 6.0.
Binoculars and small telescopes reveal the triangular shape formed by the cluster’s brightest stars.
Small telescopes show a large, dense star cluster with a grouping of stars shaped like an arrowhead near the center. 8-inch and larger telescopes resolve dozens of stars in the cluster.

The best time of year to observe M93 is during the winter.

M93 Open Cluster

Imaging Details
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