The Small Magellanic Cloud is a satellite galaxy of the Milky Way. It’s about 200,000 light-years away, it contains hundreds of millions of stars, and it’s easily visible to the eye alone — from the southern hemisphere. And it may actually consist of two separate but related halves — two galaxies for the price of one.
Astronomers had suggested that possibility almost four decades ago. And a recent study provided the best evidence yet to support the idea. It found two large star-forming regions that are separated by about 15,000 light-years. One lines up in front of the other, making it hard to see them as individual objects.
A team studied the galaxy in several ways. It found that gas and dust are split into two distinct regions. Their material moves in different ways, and has a different composition.
The researchers also studied hot, young, bright stars. That also revealed two separate regions. And like the gas, the stars in the regions move in different ways, and have a slightly different makeup.
The team said the two regions could be remnants of two galaxies that came together long ago. On the other hand, the region that’s closer to us could be the main body of the galaxy. The region behind it then could be a tail of stars and gas pulled out by the gravity of the nearby Large Magellanic Cloud, which is bigger and heavier.
Either way, this close companion to the Milky Way may be more than meets the eye.
Script by Damond Benningfield