Busy Galaxy

Our home galaxy, the Milky Way, is like a leaky faucet. It gives birth to new stars a few drips at a time — the equivalent of no more than a few Suns per year. By contrast, a galaxy seen when the universe was young is like a fire hose: It’s giving birth to thousands of stars a year.

SPT0346-52 is so far away that we see it when the universe was just a billion years old. The galaxies of that era were stuffed with hydrogen and helium — the raw materials for making stars.

Even for that era, though, SPT0346-52 is a standout. The galaxy is only a few thousand light-years across. That means its total mass and volume are much less than one percent of the Milky Way’s. Yet it appears to be giving birth to the equivalent of as many as 4500 Suns every year. That makes it one of the most prolific star factories ever discovered — star-for-star, it’s hundreds of thousands of times busier than the Milky Way.

Astronomers are still trying to figure out why it’s so busy. It could be two galaxies that are merging. That process would slam together their clouds of gas, squeezing them and triggering a massive starburst — a torrent of new stars from a busy galaxy.

The galaxy is much too far and faint to see without a major telescope. But it’s in the constellation Horologium, the pendulum clock. From the southern half of the United States, it scoots low across the southern horizon before dawn.
 

Script by Damond Benningfield