With the demographic explosion, the energy crisis or even global warming, the life on earth is increasingly threatened. The mobilization of the scientific community for the looking for an “alternative” led to the discovery of exoplanets. The first discovery dates back to October 1995, by Michel Mayor and Didier Queloz.
The fundamental question, at least for many researchers, is: “Are there Earth twins in the universe? ». It was while trying to answer this that Prof. Liu Jifeng and his student Dr. Yang Fan from the National Astronomical Observatories of the Chinese Academy of Sciences made a discovery.
Their work led to the proof that theexoplanet KELT-19Ab has a atmosphere and that it is foggy. As a reminder, the presence of an atmosphere is part of the conditions of habitability of a planet. This therefore indicates that this planet is an interesting target for search for life.
A new feat that comes down to the technique of transit
In order to better understand the universethe human being is engaged in the space conquest. Technological advances have thus made it possible to achieve considerable exoplanetary studies.
Used particularly to discover the super-earths, the planetary transit method consists of measure the small periodic variations in the luminosity of a star when a planet in orbit passes in front of it. More than 3,000 exoplanets have been discovered using this method. The transit depth thus allows to Better know the aspects of the planet.
“The transit depths in different bands reveal the existence of KELT-19Ab’s atmosphere. »
Dr. Yang Fan
KELT-19Ab’s atmosphere has yet to be explored with powerful new telescopes like JWST, LSST or Sitian.
In addition, ofother factors also explain the transit depth differences according to the researchers. To name a few, there is the sampling rate, the modeling of the exoplanet and its host star or even the stellar variability.
Still so many mysteries to solve about life and the universe
The past decade has witnessed theacceleration of the study of the atmosphere of exoplanets thanks to the joint analysis of terrestrial telescopes and space telescopes (Hubble and TESS). And the years to come look even more promising.
For example, for a better space surveillancethe network of telescopes Sitian produced a high precision photometry.
“Sitian will detect and analyze up to 25,000 planets in ten years. This fivefold increase in the sample of planets and the interesting targets involved will greatly improve our knowledge of the planet and its atmosphere. »
Dr. Yang Fan
Scientists hope that space conquest to better understand life and its place in the universe.
SOURCE: MIRA NEWS