The James Webb Telescope detected water vapor while observing the passage of this planet in front of its star!

The great exobiologist Carl Sagan realized that the discovery of life somewhere other than Earth, and more intelligent life at least as technologically advanced as ours, would have major philosophical and social ramifications. It would indeed be an important discovery in this regard if we could at least determine the extent and extent of the Earth biospherebiosphere rare or not in milky waymilky way. During his interview with Futura, Jean-Pierre Biebring put forward the thesis that, according to him, Earth and life were products of many contingent events depending on certain local conditions that one could “expect to never find.”externalexternal In the Milky Way and maybe even further afield.

The question is still very much open and ectobiologists are working on an answer. For example, they seek to determine habitability outer planetsouter planets rocky in orbitorbit about the red dwarfsred dwarfs. They are already more stars galaxygalaxy. But one wonders if they are pro-life.

Explanations by Frank Celsis, Astrophysicist, LAB, Purdue University. Starlight: The best and worst thing in life! ” Born under a lucky star Phase Three of the AstrobioEducation Journey. During this video you will hear about the Tatooine planets inspired by the universe star Wars, and you will know if it could be habitable. © French Society of External Biology

A super-Earth sterilized by a red dwarf?

Red dwarfs are cooler and less luminous sunsunthere habitable areahabitable area It would be naive to allow the average surface temperature of a rocky exoplanet orbiting these stars to be consistent with that of water. liquidliquid much closer toa stara star host than in case solar systemsolar system. However, red dwarfs are very angry at the beginning of their long existence, which results in significant floods X rayX ray And ultravioletultraviolet. The question then arises whether rocky exoplanets in this region could hold enough water and a atmospheresatmospheres protection to allow life to flourish, water molecules being able to separate by these radiations and the atmosphere sometimes being able, as was the case on Mars but not from VenusVenuscompletely eroded by windswinds and stellar flares.

There is only one way forward to solve these questions, to study rocky exoplanets near red dwarfs, knowing in particular that the presence of certain atmospheres makes it possible to get a more complex idea of ​​what we must wait for conditions to make an exoplanet habitable.

A group of astrophysicists has just used the instruments of the James Webb Telescope (JWSTJWST) to monitor usage spectrometerspectrometer Close InfraredInfrared from web (NIRNIR) Super-Earth GJ 486 b. It is not in the naive habitation zone because it orbits in less than 1.5 Earth days around GJ 486, and its average surface temperature should be about 430 degrees Celsius.

Use these researchers TransitTransit for about an hour trying to highlight the presence of water vapor in a possible atmosphere. GJ 486 b is about 30% larger than Earth and three times more massive, which means it’s a rocky world with gravitygravity More powerful than the blue planet, perhaps strong enough to hold a water vapor atmosphere.

As indicated in the article published in Astrophysical Journal Letters Available for free at arXivAnd Astrophysicists have highlighted this water vapor near Super EarthSuper Earthor at least its existence is suggested by three different coupled analytical methods modelingmodeling Astrochemicals for a potential atmosphere.

Water vapor from stellar spots?

But, as he also explained in a NASA press release, one of the discovery’s authors, Kevin Stephenson of the physicalphysical Advance from Johns Hopkins University in Laurel, Maryland, water vapor in the atmosphere to rocky planetrocky planet The warmth would be a major breakthrough for exoplanet science. But we have to be careful and make sure that the star is not the culprit His colleague Sarah Moran, of the University of Arizona in Tucson, also in the US, adds: We see a signal, and it’s almost certainly from the water. But we can’t yet tell if that water is part of the planet’s atmosphere, which means the planet has an atmosphere, or if we just see a watery signature coming from the star. »

Paradoxically, the red dwarf’s atmosphere, which is already much less hot than in the case of the Sun, could also be locally sufficiently cool on the level of sunspot equivalents to allow water molecules to form as vapor. But the researchers acknowledged that they did not see any trace of these spots in Curve a lighta light A transit has been obtained (which is the case for some stars with exoplanets).

Observations at shorter infrared wavelengths by another JWST instrument, the Near Infrared Imager and Non-slit Spectrophotometer (NerisNeris), it will be necessary to choose between scenarios with planetary atmospheres or star spots.

But if an atmosphere with water vapor was already present on GJ 486 b, it would probably be necessary to infer that it is still continually supplied with water by volcanic eruptionsvolcanic eruptionsbecause the activity of the red dwarf must contribute to the erosion of this atmosphere.

Is Earth an ordinary world? Are all exoplanet systems like ours? How is a habitable planet built? Another video from AstrobioEducation’s educational journey. © French Society of External Biology