Astronomers using NASA’s Hubble Space Telescope have obtained a remarkable new view of a globular cluster called NGC 6535.
NGC 6535. Image credit: ESA / Hubble / NASA / Gilles Chapdelaine.
Globular clusters (globulus is Latin for small sphere) are tightly bound groups of stars which orbit galaxies.
There are about 150 known globular clusters in our Milky Way Galaxy.
All of them are estimated to be at least 10 billion years old and therefore contain some of the oldest stars in the Galaxy.
They contain an abundance of low-mass red stars and intermediate-mass yellow stars, but none greater than 0.8 solar masses.
The globular star cluster NGC 6535 is located in the constellation Serpens, approximately 22,000 light-years away.
It was first discovered in 1852 by English astronomer John Russell Hind.
The cluster would have appeared to Hind as a small, faint smudge through his telescope.
Now, over a century and a half, instruments like Hubble’s Advanced Camera for Surveys and Wide Field Camera 3 allow astronomers to marvel at the cluster and its contents in greater detail.
