Blue fairy lights brighten up a stellar city

This amazing image of brilliant blue and contrasting red giant stars is the young, open star cluster Messier 47, which is located approximately 1600 light years away.

Open clusters are stellar cities containing loosely bound collections of up to a few thousand stars, which were all formed at about the same time.

Although it is bright and easy to see, Messier 47 is one of the least densely populated open clusters visible from Earth, with only around 50 stars in a region 12 light-years across, compared to other clusters which usually contain thousands of stars.

Astronomers learn a great deal of information about stars by their colours.

The bright blue-white stars in this image are denser and hotter than the red giant stars, which were more massive and burn through their fuel faster.

More than 1100 open clusters have so far been discovered in the Milky Way Galaxy, and many more are thought to exist.

Messier 47 is located in the constellation Puppis, which is the poop deck — the deck above the rear cabin — of the mythological ship Argo.