Water discovered in an exoplanet-forming region: it could be a turning point! video

James Webb first detected water within a planetary disk with a rocky exoplanet 370 light-years from Earth

Using the James Webb Space Telescope, scientists have detected water in the inner region of a disk of gas and dust around young star PDS 70 where a rocky exoplanet is forming. (We already know that there are two gas giant exoplanets.) Astronomers expect terrestrial planets to form in that region. This is the first discovery of its kind in a disk that hosts at least two planets. Any rocky planets produced in the inner disk would benefit from a large reservoir of water, which would improve their chances of living. This discovery provides evidence of a mechanism for providing water to potentially habitable planets already during their formation, as well as for the subsequent impacts of water-bearing asteroids.

Water is essential to life Land. However, scientists debate how it came to Earth and whether this process could make rocky exoplanets around other stars habitable. The recognized mechanism is regeneration by water-bearing asteroids bombarding the surface of a young planet. Giulia Perotti, an astronomer at the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, is the lead author of a research article that appears in the journal. natures Reporting the discovery of water in the planet-forming disk of young star PDS 70, about 370 light-years from Earth.

Water in the inner disk of star PDS 70

Observations with the Medium Infrared Instrument (MIRI) aboard the James Webb Space Telescope (JWST) revealed the presence of water near the center of the disk, near host star PDS 70. In the solar system, this is the region where rocky planets orbit the sun. According to the analysis, the water is in the form of hot steam, which burns at a temperature of about 330°C. Monitoring PDS 70 with MIRI on board the JWST was key to this discovery.

What is the origin of water?

Since the presence of water was somewhat unexpected, the MINDS team is investigating different scenarios to explain their findings. One possibility is that the water is the remnant of an initially water-rich nebula that predates the disk phase. Water is very common, especially in its frozen state, as it coats fine dust particles. When exposed to heat near a forming star, the water evaporates and mixes with other gases. Unfortunately, water molecules are very fragile and break down into smaller components like hydrogen and oxygen when exposed to harmful ultraviolet light from a nearby star. However, surrounding materials such as dust and water particles act as a protective shield. As a result, at least Some of the water discovered near PDS 70 may have escaped the destruction.

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Astronomers have already obtained more observations using ground-based telescopes to complete the picture. In addition, they are eagerly awaiting another batch of James Webb’s notes that provide detailed images of the PDS 70’s interior. Its structure may reveal hints of other terrestrial planets or slightly larger sub-Neptunes forming near the newly discovered “water reservoir”.

source: Max Planck Institute for Astronomy