In the article published today in the magazine Astronomy and astrophysicsOne of these exoplanets is described by researchers as having half the mass of Venus. “This is the exoplanet with the smallest mass measured using the radial velocity method, even smaller than Earth,” he explains. Susanna Barros (I for & Department of Physics and Astronomy Give College of Science). The article’s co-author adds that “this measurement was only possible due to many years of improvements in tools and data analysis techniques, to which IA members have made important contributions.”
In addition to this planet and another ocean world, the team also discovered so far undiscovered exoplanets in this planetary system. A fourth planet has been discovered and a fifth planet is also suspected in the habitable zone The region is at the correct distance from the star so that the planet could have liquid water on its surface.“We have found evidence to suggest the existence of a terrestrial-type planet located in the habitable zone of this system,” comments Demangeon (IA & DFA-FCUP).
These findings are an important step forward in the search for life on Earth-sized planets outside the solar system. Detecting signs of life, so-called biosignatures, on an exoplanet depends heavily on astronomers’ ability to study its atmosphere. However, current telescopes still lack sufficient diameter to reach the necessary resolution, so that this type of study can be done on small rocky planets. The L98-59 planetary system, only 35 light-years from Earth, is a good target for future observations of the atmospheres of exoplanets.
The team used the ESPRESSO instrument to study the L 98-59 system and were able to conclude that three of the planets may have water in their interiors or atmospheres. The two planets closest to the star are likely dry, but they may still contain small amounts of water. A third planet may contain up to 30% of its mass in water, so it appears to be an ocean world.
to the principal investigator Planetary Systems Team to IA, Nuno Cardoso Santos (IA & DFA-FCUP): “ESPRESSO has been meticulously engineered so that we get results like this and defy limitations in discovering other worlds. All the investments that have been made are paying off now and it is important to see that the Portuguese team is at the forefront of these results. In fact, we can To expect that in the near future we will have more news and new discoveries!”
Early in 2019, astronomers discovered three of the planets in the L98-59 system, using the transit method.6With the help of the satellite he-goat (NASA) which allowed them to calculate their volumes. However, only radial velocity data obtained by ESPRESSO and its precursor, HARPS, have been added.7(High-Resolution Radial Velocity Planet Finder), Demangon and his team were able to find more planets in this system and measure the masses and radii of the first three. “If we want to know how a planet is formed, we need, at a minimum, to know its mass and radius,” Demangon explains.
The team hopes to continue studying this system with the future James Webb Space Telescope (JWST) to NASA/who – which/CSA. tambim telescope or very large telescope (ELT) from ESO, currently under construction in the Chilean Atacama Desert and expected to begin observations in 2027, would be ideal for studying these planets. “god recruitment, which will be installed on the ELT, will have the ability to study the atmospheres of some planets of the L98-59 system, thus completing JWST from the ground up,” says Maria Rosa Zapatero Osorio, an astronomer at the Centro de Astrobiology Madrid (Taxi) and co-author of the article.
“This system tells us what’s going to happen,” Demangon adds. “As a society, we have been looking for terrestrial-type planets since the birth of astronomy. Now we are getting closer and closer to discovering a terrestrial planet in the habitable zone of its star, whose atmosphere it is possible for us to study.”
The participation of artificial intelligence in ESPRESSO is part of a broader strategy to enhance the search for exoplanets in Portugal, through the construction, development and scientific definition of various space instruments and missions, such as the mission Khufu (European Space Agency), already in orbit. This strategy will continue for years to come with the launch of the space telescope plateau(ESA), Mission Ariel (ESA) and installation of the HIRES spectrometer on the largest next-generation telescope, ELT (ESO).
(Institute of Astrophysics and Space Sciences)