November 22, 2022
For centuries, no one knew if we were alone in the universe—or if there were even other planets like ours.
But thanks to new telescopes and methods in the past decades, we now know there are thousands and thousands of planets out there circling faraway stars, and they come in all sorts of shapes and sizes—large and small, rocky and gaseous, cloudy or icy or wet.
A study by scientists with the University of Chicago, the University of Michigan and the University of Maryland suggests another for the list: planets with helium atmospheres. Moreover, the discovery may suggest a new step in our understanding of planet evolution.
Their simulations found that it’s likely that helium would build up in the atmospheres of certain types of exoplanets over time. If confirmed, this would explain a decades-long puzzle about the sizes of these exoplanets.
“There are so many weird and wonderful kinds of exoplanets out there, and this finding not only adds a new kind but may have implications for understanding the evolution and formation of planets in general,” said University of Chicago astrophysicist Leslie Rogers, a co-author of the new paper published in Nature Astronomy.