Recently, as the Hubble Space Telescope performed a sweep of space, it picked up on an image that astronomers said looked like a “pale rose in the sky”. On closer inspection, it looked as though the pale rose could be the bloom of a galactic merger.
The galaxy which has been dubbed PGC 6240 is nestled in the water snake constellation known as Hyrdrus. The structure of the galaxy itself is quite strange, with a bright center and then spiraling shells of stars circling it. Some of the stars appear to be compact whereas others are so far apart that they barely seem to be connected to PGC 6240 at all. Surrounding the galaxy in nearby space there are the star clusters that are expected around any galaxy. Our own galaxy has such clusters surrounding it.
Clues In The Clusters
Under normal circumstances, clusters of stars will have been created at the same time as the galaxy. This means that the stars within the clusters and the clusters will all be a similar age to the galaxy that they surround. However, in the case of the ‘pale rose’, astronomers have found that the compact groups of stars differ from the norm. In this case, the star clusters are made up of stars which vary in age. This very fact points towards a galactic merger.
If two galaxies collide with each other, a galaxy would definitely have a noticeable alteration in its structure. Also, the collision would cause an increase in the formation of stars, hence the younger stars being mingled in with the older stars.
The Hubble Space Telescope is the brainchild of NASA and the European Space Agency. The 23 year old telescope orbits the earth at an average altitude of 569km (353 miles) every 97 minutes. Thanks to the continued success of the Hubble telescope, we are able to pick up on galactic occurrences like PGC 6240.
[Image via Hubble Space Telescope]