In a world first, James Webb peers at alien worlds as they form

The formation of distant alien worlds can teach us a great deal about the formation of our own solar system.

Chris Young
In a world first, James Webb peers at alien worlds as they form
An artist's impression of a forming planet.ESO / L. Calçada

Planets form in massive disks of dust and gas known as protoplanetary disks.

While scientists have imaged dozens of these disks in the past, they have only directly observed two planets in the formation process.

Now, a team of scientists hopes to dramatically increase this number using the James Webb Space Telescope. 

To do so, they have trained its instruments on protoplanetary disks that were previously imaged by telescopes like Hubble.

They haven’t observed a forming planet yet, but they will hope it’s only a matter of time. Webb is, of course, designed to peer through massive veils of cosmic dust.

Searching for newly-formed planets

The scientists combined images captured by James Webb with previous observations made by the Hubble Space Telescope and the Atacama Large Millimeter Array (ALMA). Their results are published in three different papers in The Astronomical Journal.

They captured images of protoplanetary disks HL Tau, SAO 206462 and MWC 758. Based on the Hubble and ALMA observations, they hoped to capture nascent planets using Webb. While they didn’t directly observe a newly-formed planet, their observations surprised them.

“Several simulations suggest that [a] planet should be within the disk, massive, large, hot, and bright. But we didn’t find it. This means that either the planet is much colder than we think, or it may be obscured by some material that prevents us from seeing it,” Gabriele Cugno, a co-author on all three papers, explained in a press release.

“What we have found is a different planet candidate, but we cannot tell with 100% certainty whether it’s a planet or a faint background star or galaxy contaminating our image. Future observations will help us understand exactly what we are looking at.”

Understanding the role of Jupiter in our Solar System

The scientists have yet to directly capture a planet in the formation process using James Webb, but they will keep trying. To be precise, they hope to find Jupiter-like planets that could shed new light on our own solar system.

“Only about 15 percent of stars like the sun have planets like Jupiter. It’s really important to understand how they form and evolve, and to refine our theories,” explained University of Michigan astronomer Michael Meyer. 

Understanding how protoplanetary disks interact with newly-formed gas giants will help scientists better understand Earth’s evolution. That’s because Jupiter has played a key role in our Solar System.