NGC 1821 is a globular cluster located in the constellation Horologium. It is approximately 100,000 light-years away from Earth and is part of the Milky Way galaxy. Globular clusters like NGC 1821 are dense collections of stars that are tightly bound by gravity. Discovered in 1834 by astronomer John Herschel, NGC 1821 contains several hundred thousand stars. Its age is estimated to be around 12 billion years, making it one of the older star clusters in our galaxy. The cluster's bright core and rich stellar population make it an interesting object for astronomers studying the formation and evolution of stars.