I realised I hadn't done a shot of Omega Centauri for several years, so I decided to image it the other day. In this image I have focused on bringing out the different colours of the stars in this massive globular.
Visible is a large amount of 'blue stragglers', stars that are too hot and massive for the cluster's otherwise old age.
Given the ancient origin of the cluster these stars should have turned into red giants by now but it has been proposed that they are the results of mergers and mass transfers in the crowded environment of globular clusters. A main sequence star can exist for billions of years in the cluster and then later gain mass from a close orbiting binary, or as a result of a collision/merger, and thereby become more massive and hotter so that it now appears as a blue giant.
The image is a 2x2 mosaic of 100 x 7s taken with ToUCam Pro SC1 and 10" Newton with no filters.
Hope you enjoy
Regards,
Rolf