Astronomy Picture of the Day

Explanation: Stars come in bunches. Of the over 200 globular star clusters that orbit the center of our Milky Way Galaxy, 47 Tucanae is the second brightest globular cluster (behind Omega Centauri). Light takes about 13,000 years to reach us from 47 Tuc which can be seen on the sky near the Small Magellanic Cloud in the southern constellation of Tucana. Also known as NGC 104, the dense cluster is made up of several million stars in a volume only about 120 light-years across. Its population of red giant stars are particularly easy to see in this picture. The globular cluster is also home to exotic x-ray binary star systems.