The James Webb Space Telescope has discovered a strange planet-forming disk around a young star called XUE 10. The disk has a surprisingly high amount of carbon dioxide and very little water. This is not what astronomers expected to find.
Planets usually form in disks of gas and dust around new stars. In the warm inner parts of these disks, water is usually found as a vapor. But in XUE 10’s disk, there is much more carbon dioxide than water vapor.
This challenges current ideas about how the chemistry in planet-forming disks works. The researchers think intense radiation from XUE 10 or nearby massive stars might be breaking down water molecules and changing the disk’s chemistry.
Unexpectedly carbon dioxide-rich disk
“Such a high abundance of carbon dioxide in the planet-forming zone is unexpected,” said Arjan Bik, a researcher at Stockholm University. “It points to the possibility that intense radiation is reshaping the chemistry of the disk.”
The team also found rare forms of carbon dioxide with different isotopes of carbon and oxygen. These could help explain unusual isotopes found in meteorites and comets in our own Solar System.
XUE 10 is located in a massive star-forming region called NGC 6357, about 5,550 light-years from Earth. The discovery was made by the eXtreme Ultraviolet Environments (XUE) collaboration. “It reveals how extreme radiation environments can alter the chemistry,” said team leader Maria Claudia Ramirez-Tannus from the Max Planck Institute for Astronomy in Germany.
“Since most stars and planets likely form in such regions, understanding these effects is essential for grasping the diversity of planetary atmospheres and their potential for hosting life.”
The research shows the impressive abilities of the James Webb Space Telescope to detect chemical fingerprints in distant planet-forming disks. It sheds new light on the complexity of disk chemistry in the universe.
