The fraction of exoplanets as a function of stellar metallicity. The study: “HADES RV Programme with HARPS-N at TNG XII. The abundance signature of M dwarf stars with planets” of J. Maldonado (INAF-OAPA) recently appeared on A&A

The mechanisms involved in the formation of planets are still not completely understood. The most widely accepted model that describe the formation of gaseous planets is the core-accretion model. In this paradigm, the formation of these planets starts with the formation of a large rocky core by the coagulation of planetesimals, followed by the accretion of a large gaseous envelope

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An Hot Jupiter that may not be there. The study: “The GAPS Programme at TNG. XXVII. Reassessment of a young planetary system with HARPS-N: is the hot Jupiter V830 Tau b really there?” of M. Damasso (INAF-OATo) recently appeared on A&A

Some of the exoplanets known so far belong to classes that do not exist in our Solar System. For instance,  the class of the Hot Jupiters, i.e., gaseous giant planets orbiting at close distances from their stars (typically less than 0.5 AU, Astronomical Unit, where a 1 AU is the average distance between Sun and Earth, about 150 million km).

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A super-Earth orbiting around an old M star. The study: “GJ 357 b. A super-Earth orbiting an extremely inactive host star” of Modirrousta-Galian (UNIPA/INAF-OAPA) recently appeared on A&A

Despite theoretical models predict a large abundance of Earth-like planets in our Galaxy, the family of the 4284 planets discovered so far (updated at 2020/9/25, credits: NASA) counts relatively a few of such a planets. This is clearly an observational bias, due to the fact that the methods used to detect planets are not sensitive to small planets. For this

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Neptunians and super-Earths in systems with “cold” Jupiters as test for planetary migration theories. The study: “The GAPS programme at TNG. XXIV. An eccentric Neptune-mass planet near the inner edge of the BD-11 4672 habitable zone” of D. Barbato (UniTo/OATo) and M. Pinamonti (OATo) recently appeared on A&A

The architecture of planetary systems is result from both the planet formation process and a complex mechanism of radial migration of planets. This has occurred also in the Solar System, whose final architecture resulted from the migration of the gaseous giants. In particular, the theories describing the formation and migration of super-Earths and Neptunian planets predict different configurations of the

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Exoplanets with extended evaporating atmospheres. The study: “The GAPS programme at TNG. XXII: The GIARPS view of the extended helium atmosphere of HD 189733 b accounting for stellar activity” of G. Guilluy (UniTO/INAF-OATo) recently appeared on A&A

The number of known exoplanets discovered so far (4197 planets, updated at 2020/August/4th, from NASA) is large enough to allow us to study their global properties. One of these properties, still lacking a proper explanation, is the so-called “Neptunian desert”, e.g. the lack of intermediate planets with orbital periods shorter than 3 days. One of the hypotheses that can explain the Neptunian

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Atmosphere and habitability in terrestrial planets. The study: “A systematic study of CO2 planetary atmospheres and their link to the stellar environment” of A. Petralia (INAF-OAPA) recently appeared on MNRAS

Terrestrial planets are common in the Milky Way. It has been estimated, in fact, that at least 30% of stars in the Solar neighborhood host a terrestrial planet, and this fraction increases to 40% considering the habitable zone around all M stars (e.g. stars with effective temperature between 2400 and 3700 degrees) of the Galaxy. The habitable zone is defined

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How to correct from systematics high-precision photometric data. The study: “Principal component analysis to correct data systematics. Case study: K2 light curves” of A. Petralia (INAF-OAPA) recently appeared on Experimental Astronomy

Several fields in modern astronomy rely on high-precision photometric data. This is true, in particular, for the search of exoplanets with the method of transits. This method consists in searching very small periodic dimming of stellar emission due to the transit of planets along the line of sight during their orbits. For instance, the transit due to a Hot Jupiter (a gaseous

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Hot Jupiters around young stars. The study: “The GAPS Programme at TNG. XXI. A GIARPS case study of known young planetary candidates: confirmation of HD 285507 b and refutation of AD Leonis b” of I. Carleo (Van Vleck Observatory/INAF-OA Padova) recently appeared on A&A

The discovery of the first exoplanet in 1995 was a challenge to our knowledge of the architecture of planetary systems. The planet orbiting around the star 51 Peg, in fact, was different than the planets in our Solar System: it was a gaseous giant orbiting at only 0.05 Astronomical Units (A.U., where 1 A.U. is the average distance between Earth

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Thermal inversion in the atmosphere of a ultra-Hot Jupiter. The study: “Neutral Iron Emission Lines from the Dayside of KELT-9b: The GAPS Program with HARPS-N at TNG XX” of Pino L. (INAF/OA Arcetri; University of Amsterdam) recently appeared on ApJ

Hot Jupiters are gaseous planets orbiting very close to their stars, typically closer than 0.1 Astronomical Units (the average distance between Earth and Sun), and with very short orbital periods of days or even hours. An extreme sub-class of these planets are the ultra-Hot Jupiters. These planets are tidally-locked to their stars (which means that they show always the same

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