What is the Small Magellanic Cloud?

The Small Magellanic Cloud is a nearby dwarf galaxy, located only 200,000 light years from the Milky Way, about two galactic diameters distant. It is visible from latitudes south of about 15°S. The Small Magellanic Cloud is accompanied by the Large Magellanic Cloud, separated in the sky by about 25°, which corresponds to about 75,000 light-years in actual distance. The Magellanic Clouds look like detached pieces of the Milky Way. They are among the most distant objects that can be seen with the naked eye, the most distant being the Triangulum Galaxy at 3 million light years.

The first Europeans to observe the Magellanic clouds were on the expedition of Ferdinand Magellan, the Spanish explorer, while he was circumnavigating the globe in 1519-1522. The "clouds" look vaguely like small glittering clouds in the night sky, but they are actually galaxies. Until the discovery of the Sagittarius Dwarf Elliptical Galaxy in 1994, the Small and Large Magellanic Clouds were thought to be the galaxies closest to the Milky Way.

With a high-powered telescope, the detail of the Small Magellanic Cloud is brought out. It looks gorgeous, like a blue ribbon of star-studded silk floating in space. The Small Magellanic Cloud contains several hundred million stars, few in comparison to the Milky Way's 200 billion to 400 billion stars. Because of its distance, the visible light we see of the Small Magellanic Cloud is 75,000 years old. In other words, if the Small Magellanic Cloud were to cease existing tomorrow, it would take us 75,000 years to figure it out.

The Magellanic Clouds are irregular galaxies that appear to have started off with a barred spiral structure like the Milky Way, which eventually deteriorated. It was once thought that they both orbited by the Milky Way, but recent evidence has shown this is not the case. The Magellanic Clouds and the Milky Way are only both part of the same gravitationally bound family, the Local Group, which contains over 30 galaxies including the Andromeda Galaxy and the Triangulum Galaxy.