A new study published in the Astrophysical Journal Letters suggests that planets like Earth, including those with water, could form even in the harshest known star-forming environments. These environments, drenched in intense ultraviolet radiation from massive stars, were previously thought to be too hostile for planet formation.
Artist's impression of the massive star-forming region, with the planet-forming disk XUE1 in the foreground. The region is drenched in UV light from massive stars, one of which is visible in the top left corner. The structure near the disk represents the molecules and the dust found by the researchers in their new observations. Image credit: Maria Cristina Fortuna (www.mariacristinafortuna.com)
The study, led by María C. Ramírez-Tannus of the Max Planck Institute for Astronomy, and co-authored by Dr Tom Haworth from QMUL's Astronomy Unit, used the James Webb Space Telescope (JWST) to peer into the inner region of a disk of gas and dust surrounding a young solar-type star located in one of the most extreme environments in our Galaxy. These disks are where planets form around nascent stars.
The observations made with the JWST are the first of their kind. Previous detailed observations of planet-forming disks had been limited to nearby star-formation regions that contain no massive stars. This is because the intense UV radiation from massive stars disrupts the formation of planets.
The new observations show that, even in this harsh environment, the inner regions of the disk contain both water and simple organic molecules. This suggests that planets like Earth could form in these environments, even if they are exposed to intense UV radiation.
Dr Haworth said: "JWST is providing us with an unparalleled view of the inner parts of planet-forming disks of material around young stars, where terrestrial planets like the Earth are eventually found. Most of these studies have focused on planet-forming disks quite close by to the Sun which are in environments where there are not many other stars and not much UV light. But most stars form in much larger groups with massive stars that emit trillions of times more UV light than the sun. UV light strips away the planet forming material from the outer disks, but here we see for the first time that the material in the terrestrial planet forming part of the disk actually seems to survive that process quite well. There is still lots to do, but speculatively we might therefore expect that terrestrial planet formation can happen even in the most extreme environments."
The findings of this study are good news for the search for Earth-like planets and for the possibility of life in the universe. They suggest that there are many more potential places where Earth-like planets could form than previously thought.
The researchers are now planning to conduct further observations with the JWST to study a larger sample of disks in extreme environments. They hope to learn more about how these environments affect the formation of planets and how common Earth-like planets are in these environments.
This is an exciting time for the search for Earth-like planets. The JWST is providing us with a new window into the universe, and it is already revealing new possibilities for the formation of planets like our own.