The early universe was a much different place than our own, and astronomers don’t fully understand how young stars arose in that environment. And while instruments like the James Webb Space Telescope will pierce the early epochs of star formation, we don’t always have to work as hard — evidence may be closer to home.
Star formation is a complex business. To create a small star, you have to start with a large amorphous cloud that looks like a bubble of gas and dust and compress it to the desired density stimulating nuclear fusion. For this process to work, you also have to remove a lot of heat. This is because when a gas cloud is compressed it gets hotter, and a hot gas cloud can stay in equilibrium forever. So, when a gas cloud compresses, you also have to remove heat from the system so it can compress more.
Modern day gas clouds do this by emitting radiation as they compress, and elements heavier than helium (in the world of astronomy, these are commonly called metalDo a great job of removing heat from collapsed gas clouds. But in the early universe, these gas clouds were much more primitive, containing little or no metals.
Astronomers don’t understand yet How did the stars arise? In a mineral poor environment.
One way to tackle this problem is to use massive observatories such as the James Webb Space Telescope. Another approach led by Professor Toshikazu Onishi of Osaka Metropolitan University and Associate Professor on the project Kazuki Tokuda of Kyushu University is to look nearby. Like the Small Magellanic Cloud.
The Small Magellanic Cloud is not quite as pure as the ancient universe, but it contains much less minerals than average in the Milky Way. And as an added bonus, it’s much more within our reach than the early universe.
The international team of astronomers recently used ALMA, the Atacama Large Millimeter/submillimeter Array and Caught a baby star in the formation process. They noticed very fast outflows from the newborn star. These flows are driven by incredibly strong electric and magnetic fields in the gas cloud as it is compressed.
Astronomers believe that these types of outflows dampen the rotational motion of gas around the newly formed star. This slowdown increases the rate of growth, which could lead to larger stars. More research will reveal whether this was a common way to build stars in the early universe, and likely lead to stars much larger than the modern-day average.