Newborn stars rapidly binge on material found in surrounding disks of gas and dust, according to a recent analysis of data collected by NASA’s retired Spitzer Space Telescope.
Astronomers studied Spitzer’s observations of protostar outbursts in the Orion constellation’s star-forming clouds between 2004 and 2017. The findings, printed in The Astrophysical Journal Letters, will help astronomers understand how stars grow, and how these early feeding frenzies affect the formation of planets.
“By cosmic standards, stars grow rapidly when they are very young…. It makes sense that these young stars have the most frequent bursts,” said Tom Megeath, an astronomer at the University of Toledo who co-authored the study, in a NASA statement. The project was led by Wafa Zakri, a professor at Jazan University in Saudi Arabia.
Orion’s clouds include stars that are less than 100,000 years old — the cosmological equivalent of a seven-hour-old infant — and are known as Class 0 protostars. Bursts of light from these stars were seen nearly a century ago and have rarely been seen since. These outbursts are compared to burps, as the young stars feast on the material found in the surrounding clouds.
The data shows a likely burst rate for the youngest stars at roughly every 400 years. This is much more frequent than what has been observed of 227 older protostars in Orion.
The early development of stars is difficult to study because young stars are often hidden inside the clouds from which they formed. Spitzer, which shut down in 2020 after a 16-year run, was able to observe the stars and see through the dust and gas clouds because it watched the universe in infrared. Megeath said it is possible our own Sun had a similar feeding frenzy in its younger days.
“The Sun is a bit bigger than most stars, but there’s no reason to think that it didn’t undergo bursts,” he said. “It probably did. When we witness the process of star formation, it is a window into what our own Solar System was doing 4.6 billion years ago.”