Tag: esopianeti

A young and low-density planet for DS Tucanae A. The study: “Constraints on the mass and atmospheric composition and evolution of the low-density young planet DS Tuc A b” of S. Benatti (INAF – OAPa) recently appeared on A&A

Ricerca

The study of planets orbiting around young stars (younger than 100 million years) can help astronomers understanding the physical processes setting the early evolution of planetary systems. However, young stars are typically characterized by rapid rotation and intense magnetic activity, phenomena which produce photometric and spectroscopic signals that can mimic and confuse those due to the presence of planets. It

» Read more
, , , , ,

A sub-Neptunian exoplanet around the star GJ 720 A. The study: “HADES RV Programme with HARPS-N at TNG XIII. A sub-Neptune around the M dwarf GJ 720 A” of E. González-Álvarez (CSIC-INTA) recently appeared on A&A

Ricerca

About 19.3% of the 4001 exoplanets confirmed to date were discovered with the technique of the radial velocity (from https://exoplanets.nasa.gov/). This method consists in using time series of spectroscopic observations in order to measure the periodic oscillations of the position of stars due to the presence of orbiting exoplanets. In fact, in a planetary system both the planets and the

» Read more
, , , , , , ,

The chemical composition of the Hot Jupiter HD 209458b tells us about its history. The study: “Five carbon- and nitrogen-bearing species in a hot giant planet’s atmosphere” of P. Giacobbe (INAF – OATo) recently appeared on Nature

Ricerca

The discovery of the first planet orbiting around another star occurred in the 1995, thanks to the astronomers Michel Mayor and Didier Queloz. This discovery set a milestone in astronomy both because it was the first observational confirmation of the existence of planets orbiting around other stars (in this case 51 Pegasi), and because of the nature of this exoplanet. It

» Read more
, , , , , , ,

Composition of a sub-neptunian exoplanet with TESS and ESPRESSO. The study: “A sub-Neptune and a non-transiting Neptune-mass companion unveiled by ESPRESSO around the bright late-F dwarf HD 5278 (TOI-130)” of A. Sozzetti (INAF-OATo) recently appeared on A&A

Ricerca

The NASA satellite Transiting Exoplanet Survey Satellite (TESS) it’s one of the most effective telescopes to search for exoplanets. TESS is designed to find exoplanets with the transits method, e.g. by observing the periodic occultations of stars by their planets during their orbits. To date, about 27% of the exoplanets discovered with TESS belong to the class of the sub-neptunians. These planets have a

» Read more
, , , , , ,

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

Ricerca

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

» Read more
, , , , , , , ,

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)

Ricerca

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

» Read more
, ,

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

Ricerca

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

» Read more
, , , , , ,

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)

Ricerca

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

» Read more
, , , , , , ,

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

Ricerca

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

» Read more
, , , , , , ,

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

Ricerca

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).

» Read more
, , , , , , , ,
1 2 3 4 5 6