JWST Detects Water Vapor in Rocky Planet-Forming Zone

Water is essential for life as we know it. However, scientists debate how it reached the Earth and whether the same processes could seed rocky exoplanets orbiting distant stars. The preferred mechanism is water-bearing asteroids bombarding the surface of a young planet. An international research team involving scientists from IAS has just discovered water in the inner disk of the young star PDS 70, well inside of the orbit of two growing giant planets.

This is the first relatively old disk - around 5.4 million years old - in which astronomers have found water. Over time, the amount of gas and dust in protoplanetary disks diminishes, either through the action of the star's radiation, or under the effect of giant growing planets, which sweep away the gas and block the supply of matter to the inner regions, where rocky planets form. The JWST observations of PDS 70 show that the region of rocky planet formation remains rich in water, despite the formation of giant planets similar to Jupiter or Saturn. Consequently, in addition to the water brought by a long process involving water-rich asteroids, this new result suggests that water was available from the very formation of rocky planets.

These results have been published in Nature by the MINDS collaboration which involves researchers from the Institut d'Astrophysique Spatiale. The observations were obtained within the MIRI-JWST guaranteed time programme in which IAS is part of. These results give a first glimpse of the potential of JWST to unveil the physical and chemical conditions prevailing during planet formation.

NASA/ESA Press Release : https://www.esa.int/Science_Exploration/Space_Science/Webb/Webb_detects_water_vapour_in_rocky_planet-forming_zone

Article in Nature: https://www.nature.com/articles/s41586-023-06317-9

Contact: Benoît Tabone