Archive for December, 2011

NGC 2362 (Tau Canis Majoris) Cluster – The Youngest Cluster in the Milky Way

December 31, 2011 Leave a comment

NGC 2362 (Caldwell 64) is a visually stunning open cluster of around 60 stars spread across 6′ (9 light years) in the Canis Major constellation. The cluster is located on the outer edge of the Orion-Cygnus arm of the Milky Way Galaxy. It was discovered by Giovanni Batista Hodierna before 1654 and rediscovered by William Herschel in March 1785. Its brightest star at the centre of the cluster is Tau Canis Majoris (mag 4.4), and therefore it is sometimes called the Tau Canis Majoris Cluster. NGC 2362 has a distance of 5,100 light years and is a relatively young 4-5 million years in age.  There have been numerous mistaken associations of nebulosity with this cluster and all modern researchers now agree that there is no native nebulosity. The cluster does however sit within a large bubble of HII gas associated with the Sharpless 310 nebula. The nebula may be a remnant of the clusters original nursery cloud which has otherwise been blown away by the stellar winds of the hot young stars.

The central Tau Canis Majoris star is actually a multiple star system in its own right, but the component stars cannot be resolved by smaller telescopes. The core is a close binary with two stars of equal magnitude (Rosat X-Ray satellite images).

Image taken on 1/10/2010  5.55 am New Mexico time on GRAS 3 (TAK TOA 150/FLI ML8300 one shot colour camera). RA: 07h 18m 42.1s DEC: -24° 57′ 00″ (J2000). 10 minute exposure @ 1 x 600 seconds.

Categories: Stars & Star Clusters