47 Tucanae — also known as 47 Tuc — is the second brightest globular cluster in the night sky famous for spectacular sights in the constellation Tucana. The constellation is home to a cosmic beauty called NGC 299, an open star cluster located within the Small Magellanic Cloud just under 200,000 light years away. Open clusters such as this are collections of stars weakly bound by the shackles of gravity, all of which are formed from the same massive molecular cloud of gas and dust. Because of this, all the stars have the same age and composition but vary in their mass because they formed at different positions within the cloud.
This unique property not only ensures a spectacular sight when viewed through a sophisticated instrument attached to a telescope such as Hubble’s Advanced Camera for Surveys, but also gives astronomers a cosmic laboratory in which to study the formation and evolution of stars — a process that is thought to depend strongly on a star’s mass.
