Messier 53

Messier 53 (M53) is one of the most distant globular clusters at 59,700 light years from Earth. It’s also one of the largest with a diameter of more than 220 light years and one of the most populous with 500,000 member stars.

M53 also contains a very large number of blue stragglers at almost 200 of them. Blue stragglers are stars that appear brighter and bluer than we would expect given the cluster’s age. Scientists are not sure what causes this, but one prominent theory suggests they are the result of star collisions in a densely packed cluster or they form when one star siphons mass from another star.

Globular clusters are ancient collections of stars that are gravitationally bound together in a spheroidal shape. Some are almost as old as the universe itself. They can contain anywhere from tens of thousands of stars to millions of stars. The stars they house tend to be very old as well, because star formation inside the cluster has largely ceased. The formation of globular clusters is not well understood. Current research leans toward the idea that they formed from very dense molecular clouds in the early universe. Some larger globular clusters may once have been dwarf galaxies whose larger star populations were stripped away from the core by larger galaxies.

M53 Facts

Distance: 59,700 light years

Number of stars: 500,000

Diameter: 220 light years

Age: 12.67 billion years