Is there really water in the atmosphere of K2-18b?

There may be water vapor around K2-18b, but at this time we are not sure.French astrophysicist Bruno Bézard, from the Paris-PSL Observatory, told AFP.

Calculations performed using data from the time determined that methane was detected instead of water, according to the study published in Astronomy of Nature.

Although, moreover, the scientist wants to believe that there is not only methane, but also water vapor in the atmosphere of the planet, located in the constellation of Leo 110 light years from the solar system.

The announcement in 2019 shook the world of planetary scientists, as it concerned the first – and until now the only – exoplanet located in the so -called habitable zone of its solar system. That is, a star is located, like Earth, at a distance not too close or too far from its star to make life possible there.

At a mass equal to eight times that of our planet, K2-18b qualifies as super-Earth or mini-Neptune. The 2019 study used observations made by the Hubble Space Telescope to study the light filtered by the planet’s atmosphere. Their results revealed, according to them, the molecular signature of water vapor.

A team of scientists from the Paris Observatory and the German Max Planck Institute took this data. It does not dispute the possibility of detecting the presence of water there, but confirms that the signals recorded may be due to methaneaccording to Mr. Bézard.

He questions in particular the fact that the 2019 study excluded any scenario where the atmosphere contains methane, a gas composed of carbon and hydrogen. We don’t see why they favored models where there is no methanehe said.

The justice of the peace responsible for deciding the case is in his post: the James Webb space telescope, which is better than Hubble, will soon go into service. The time to observe the environment of K2-18b is already scheduled there, according to Mr. Bézard. With this, we can know if there is water vapor and in what proportionhe concludes.