Category: Ricerca

A super-Earth for the star GJ 740. The study: “A super-Earth on a close-in orbit around the M1V star GJ 740. A HADES and CARMENES collaboration” of B. Toledo-Padrón (IAC) recently appeared on Astronomy & Astrophysics

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In the last years, stars of spectral class M (which are stars with effective temperatures between 2400 and 3700 K and masses between 0.08 and 0.45 solar masses) have been extensively observed for the search of exoplanets. This both because they are the most abundant class of stars in the Galaxy, and because the low star/planet mass ratio, compared to

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The program “Testing protoplanetary disk evolution and brown dwarf formation in starburst: NIRCAM and MIRI observations of the young cluster Westerlund 1” of M. G. Guarcello (INAF – OAPA) is among the accepted proposals of the JWST Cycle 1

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The James Webb Telescope (JWST) will be the most complex and powerful telescope ever launched into space. Built by a consortium formed by NASA, ESA, and the Canadian Space Agency (CSA), thanks to its primary mirror with a diameter of 6.5 meters (for comparison, the mirror of the Hubble Space Telescope has a diameter of 2.5 meters) and its four

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Two Neptunians for a young star. The study: “The GAPS Programme at TNG XXVIII. A pair of hot-Neptunes orbiting the young star TOI-942” of I. Carleo (Wesleyan University/INAF-OAPd) recently appeared on su A&A)

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The exoplanetary systems discovered so far (3212 systems with a total of 4331 exoplanets, as reported by https://exoplanets.nasa.gov/ on January 21st 2021) show a great variety of systems architecture, with some configurations which are completely different than that of our Solar System. This variety of architectures is a challenge for studies of the planetary formation process and all mechanisms that contribute in

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Photospheric spots and planetary transits. The study: “Correcting the effect of stellar spots on ARIEL transmission spectra” of G. Cracchiolo (UNIPA, INAF-OAPA) appeared on MNRAS

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A “transit” occurs when we observe a planet moving across the disc of its star. Thus, during the transit the planet obscures a small portion of its star, slightly reducing its luminosity. While in the Solar System the only planets we can observe transiting in front of the Sun are Mercury and Venus, transits is still the most efficient method

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Chemical composition and elevation of the atmosphere of WASP-121b. The study: “Atmospheric Rossiter-McLaughlin effect and transmission spectroscopy of WASP-121b with ESPRESSO” of F. Borsa (INAF-OA Brera) recently appeared on A&A)

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Ultra-hot Jupiters are gaseous planets orbiting at close distances from their central stars, with rotation periods shorter than 3 days. Their atmospheres are thus heated, more than 2000 degrees, by the incident radiation emitted by the central star. For this reason, the atmospheres of ultra-hot Jupiters shows peculiar properties compared with planets of other types. For instance, they are affected

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Winds and jets from protoplanetary disks. The study: “The Evolution of Disk Winds from a Combined Study of Optical and Infrared Forbidden Lines” of I. Pascucci (The University of Arizona) recently appeared on A&A

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The study of protoplanetary disks (which are disks orbiting around young pre-main sequence stars) is of great interest since planets formation occurs in these structures. Disks are dispersed in a few million years (typically less than 10 Myrs) by the planets formation itself, the accretion of material onto the central star, and the loss of material launched in a highly

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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

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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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A study on stellar clusters to calibrate the relation between Lithium abundance and age. The study: “The Gaia-ESO Survey: Calibrating the lithium-age relation with open clusters and associations. I. Cluster age range and initial membership selections” of M. L. Gutiérrez Albarrán (Universidad Complutense de Madrid) recently appeared on A&A

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Determining stellar ages can be a difficult task. One of the main difficulties is due to the fact that methods to evaluate stellar ages are specialized for given types of stars and they do not work for the others. Besides, during the longest phase in stellar evolution, the Main Sequence, stellar parameters such as radius and temperature do not change

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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

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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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MHD simulations connecting supernova explosions and SNR. The study: “Three-dimensional modeling from the onset of the SN to the full-fledged SNR. Role of an initial ejecta anisotropy on matter mixing” of A. Tutone (UNIPA/INAF-OAPA/INAF-IASF) recently appeared on A&A

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Supernova explosions, occurring and the end of the life of massive stars, are ruled by a complex physics, and they can not be described by a simple spherically symmetric geometry. The rarity of these events make even more difficult to understand the physical processes involved during the explosions. For instance, on average only one supernova explodes in our Galaxy every

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