Astronomers Catch Rare Sight of Incredibly Massive Star's Formation

The star is so big, other smaller stars could be forming in orbit around it.

Most Popular
Artist's impression of the disk and outflow around the massive young star.
Advertisement - Continue Reading Below

The biggest stars in the galaxy take about 100,000 years to form, which is the blink of an eye in astronomical terms. (A smaller star like the sun takes millions of years to form.) So it is rare to find a star more than eight times the mass of the sun (big enough to supernova at the end of its life) while it is still forming, and astronomers led by the University of Cambridge just found one that is more than 30 times the mass of the sun, and still growing.

Most Popular

The forming star, or protostar, is about 11,000 light years away, in a much denser and more volatile region of the galaxy. This is another reason it can be hard to find young massive stars among the 100 billion stars in the Milky Way—they tend to form far away from our calm little galactic neighborhood.

The find represents an exciting opportunity to study one of the most massive stars in the galaxy while it begins its short and violent life. The researchers discovered that the star is forming from the center of a rotating disk of gas and dust, called an accretion disk, just like smaller stars such as the sun. However, the newly discovered star and its surrounding disk are so massive that it is possible that not only planets, but other stars will form within the accretion disk to ultimately orbit the bigger host star—a solar system of smaller solar systems.

The findings were published today in the Monthly Notices of the Royal Astronomical Society, and the research will be presented this week at the Star Formation 2016 conference held at the University of Exeter.

"Our theoretical calculations suggest that the disk could in fact be hiding even more mass under layers of gas and dust," said Duncan Forgan, a researcher at the University of St. Andrews' School of Physics and Astronomy, in a press release. "The disk may even be so massive that it can break up under its own gravity, forming a series of less massive companion protostars."

The star was located using radio wave observations taken with two telescope arrays, the Submillimeter Array (SMA) in Hawaii and the Karl G. Jansky Very Large Array in New Mexico, to look through a thick cloud of infrared gas and dust—a cold and dense region of space with plenty of material for stars to form. Further observations with the Atacama Large Millimeter Array (ALMA) in Chile, one of the most powerful telescopes in the world, will reveal any potential companion stars forming around the young giant and help astronomers learn more about the short lives of massive stars.

Read Next: