Due to maintenance work, NICS is temporarily not available. Sorry for the inconvenience.

The competition ‘Young Astronomers at the Telescopio Nazionale Galileo: II Edition’ is open to students (15-17 years old) attending Italian high schools with the aim of promoting their skills in science and technology, offering them new opportunities for comparison, growth and achievement in science and its applications. Furthermore, it promotes the ability to work as a team, with the purpose of exploring and appreciating the wonders of the Universe.

Thanks to infrarred observations taken with the high-resolution spectrograph GIANO-B installed at the Telescopio Nazionale Galileo, a team led by M. Basilicata (University of Tor Vergata, Rome and INAF ‐ Astrophysical Observatory of Turin), detected for the first time water vapour in the atmosphere of two extra-solar planets and suggested a possible formation scenario.

The HCT collaboration (HARPS-N Collaboration Time) discovered and characterized two planets orbiting TOI-1453 and spanning the radius valley. Using data coming from the high resolution spectrograph HARPS-N (High Accuracy Radial velocity Planet Searcher for the Northern hemisphere) installed at the Telescopio Nazionale Galileo and the NASA’s TESS (Transiting Exoplanet Survey Satellite), the team was able to identify the two exoplanets orbiting TOI-1453. The inner planet, TOI-1453 b, is a small super-Earth of about 1.2 Earth radii orbiting its star in 4.3 days. The outer planet, TOI-1453 c, is a sub-Neptune with 2.2 Earth radii which orbits its star in 6.6 days. The planets hence span the radius gap separating super-Earths from sub-Neptunes, namely the radius valley. The origin of this valley, as well as the compositional nature of sub- Neptunes, are still heavily debated. The planetary system TOI-1453 could provide important clues. The two planets are in a configuration close to the 3:2 mean-motion resonance, which is indicative of orbital migration and provides valuable insights into the formation history of this planetary system. Additionally, the old star TOI-1453 is part of a binary system (a pair of stars orbiting each other). Currently, few small planets have been characterized in binary systems, and the stellar companion to TOI-1453 might have a significant impact on the radius valley.