A comparison between different diagnostics of the age of stellar clusters. The study: “The Gaia-ESO survey: a lithium depletion boundary age for NGC 2232” of A. S. Binks (Keele University) recently appeared on MNRAS

Measuring stellar ages is a difficult task but nevertheless very important. For instance, the study of stellar evolution requires accurate estimate of stellar ages. On the other hand, we can count on very few diagnostics that can allow astronomers to obtain reliable estimate of stellar ages, and typically these methods can be applied only to specific type of stars or

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A rapid dispersion for protoplanetary disks in low metallicity. The study: ” Dispersal timescale of protoplanetary disks in the low-metallicity young cluster Dolidze 25″ of M. G. Guarcello recently appeared on A&A

Protoplanetary disks are disk-like structures that are found in low-mass stars younger than 10 million of years, typically called “pre-main sequence stars”. These disks are also the sites where planets formation occurs. In the last years, scientists have devoted a large effort to study the evolution and dispersion of protoplanetary disks. This has been possible also thanks to facilities such

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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

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

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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

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

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Jets launched during supernova explosions. The study: “X-ray emitting structures in the Vela SNR: ejecta anisotropies and progenitor stellar wind residuals” of V. Sapienza (UNIPA/OAPA) recently appeared on A&A

Supernova remnants are clouds in rapid expansion formed by supernova explosions. Typically, these remnants are very inhomogeneous. These inhomogeneity is the result of the interaction between the expanding remnant and the surrounding material, and, in particular when they are generated by core-collapse supernova explosions (which are the supernova triggered by the gravitational collapse of the cores of massive stars), also to anisotropies formed

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The interaction between expanding SNR and surrounding clouds. The study: “Modeling the mixed-morphology supernova remnant IC 443. Origin of its complex morphology and X-ray emission” of S. Ustamujic (INAF-OAPA) accepted on A&A

Supernova remnants are clouds in rapid expansion produced by supernova explosions. They are often characterized by a complex morphology, resulting from the interaction between the expanding remnants and surrounding clouds. Supernova remnants also emit radiation on a wide band of the electromagnetic spectrum. This is due to the variety of phenomena occurring in these objects, and because of the different

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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

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

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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

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

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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

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

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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