From dust to planets: James Webb Telescope’s breakthrough in cosmic ice research
Research aided by the James Webb Telescope has confirmed the critical role of ice-covered particles in planet formation. The telescope was used to focus on four protoplanetary discs.
3:14 PM EST, November 10, 2023
NASA experts explain that, according to a widely believed theory, planets form due to small, ice-covered dust particles. These particles serve as focal points for matter condensation, while also acting as sources of material. A key presumption of this theory is that these particles migrate from the distant, outer regions of the protoplanetary disc. This movement is fuelled by friction against the gas present, resulting in a loss of velocity. As these particles draw closer to the star, the water contained within them converts to vapour.
Scientists Receive Further Assistance from the James Webb Telescope
"In the past, we saw planet formation as a static process — as if planets formed within isolated zones. Now, we have evidence that these zones interact. We believe that these processes also occurred in our solar system," emphasizes co-author Colette Salyk from Vassar College in Poughkeepsie, whose research was recently published in 'The Astrophysical Journal Letters'.
Salyk and her colleagues utilised the James Webb Telescope to examine four protoplanetary discs orbiting sun-like stars. Each of these discs is only about 2 to 3 million years old, making them cosmic "newborns".
Two of the discs were described as compact, while the other two were considered large. The prevalent theory suggests that compact discs should bring a significant influx of the aforementioned particles much closer to the star than Neptune's orbit due to strong inflow. In contrast, particles within large discs should remain in various rings, extending up to six times the distance of Neptune's orbit.
The presence of water (transferred by the particles) was confirmed through observations, thus bolstering the theory. Initially, however, the scientists had difficulty interpreting the collected data.
"We were stuck for two months with preliminary results indicating that compact discs contain colder water while larger discs contain warmer water. This was perplexing because we chose stars with similar temperatures," explains Professor Andrea Banzatti.
Eventually, they discovered that the compact discs contained additional amounts of cold water at the edge of the so-called ice zone, a distance from the star roughly ten percent that of Neptune's orbit.
"Now we definitively see this excess of cold water. This signifies an unprecedented testament to Webb's high-resolution capabilities," emphasises Professor Banzatti.
