Observations of planetary cradles reveal rocky planets can form in extreme environments
Planets like our Earth, including planets with water, could form even in the harshest known star-forming environments, drenched by hard UV light from massive stars. That is a main result of analyses of new observations of such an environment with the James Webb Space Telescope (JWST). The observations are the first of their kind – before the JWST, this kind of detailed observation had not been possible. This is good news for Earth-like planets, and for life in the universe: there is a great variety of environments in which such planets can form. The results have now been published in the Astrophysical Journal Letters. Water and carbon-bearing molecules have been discovered in a disk of gas and dust surrounding a young solar-type star, which is located in one of the most extreme environments in our Galaxy. Such disks are where planets form around nascent stars. A team of astronomers led by María C. Ramírez-Tannus at the Max Planck Institute for Astronomy in Heidelberg, Germany and Arjan Bik from Stockholm University, made use of the James Webb Space Telescope to peer into the inner region of the disk, which is where planets similar to our Earth are expected to form: so-called terrestrial planets, with a thin atmosphere covering a planet made of rock. The disk, which the astronomers call XUE-1, is exposed to intense ultraviolet radiation of nearby hot, massive stars. Yet even in this harsh environment, the observations detected both water and simple organic molecules. Ramírez-Tannus says: “This result is unexpected and exciting! It shows that there are favourable conditions to form Earth-like planets and the ingredients for life even in the harshest environments in our Galaxy."
