Category: Ricerca

An Italian consortium to study the Space Weather. The paper: “SWELTO — Space WEather Laboratory in Turin Observatory” of A. Bemporad (INAF – AOTo) recently appeared on the INAF Technical Reports

Ricerca

The atmosphere of the Sun hosts a rich variety of magnetic phenomena, which are the consequence of the interaction between the solar magnetic field and the hot and highly ionized solar gas (plasma). The main magnetic phenomena occurring in the photosphere are the sunspots. They appear as dark spots in the bright solar surface, which correspond to regions with intense

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JWST, explanetary transits and starspots. The paper:”Hiding in plain sight: observing planet-starspot crossings with the James Webb Space Telescope” of G. Bruno (INAF – OA Catania) appeared on MNRAS

Ricerca

We typically observe phenomena due to the interaction between the magnetic field of Sun and its plasma, which is the hot (from 5600 K in photosphere to million degrees in the corona) gas with a high level of ionization, on the photosphere, chromosphere, and corona of our star. Some of these magnetic phenomena are starspots, faculae, prominences, and flares. In particular, solar

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Two young planets defy the models for planets formation. The study: “Rapid contraction of giant planets orbiting the 20-million-year-old star V1298 Tau” by A. Suarez Mascareno (Instituto de Astrofísica de Canarias) recently appeared on Nature Astronomy

Ricerca

Planet formation occurs in disk-like structures, called “protoplanetary disks”, observed around very young stars. The dispersal timescale of these disks (being typically 3-5 million of years) sets an important limit to the planet formation timescales predicted by theoretical models. The widely accepted model that explains the formation of the gaseous giant planets, such as Jupiter, is the “core-accretion model“. This

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The stellar population of 70 star clusters revealed by Gaia/EDR3 and the Gaia-ESO Survey. The study: “The Gaia-ESO Survey: Membership probabilities for stars in 63 open and 7 globular clusters from 3D kinematics” of R. J. Jackson (Keele University) recently appeared on MNRAS

Ricerca

Our knowledge of stellar evolution relies on our capability of obtained precise measurements of stellar ages, a challenging task for isolated stars which, however, is typically easier for stars in clusters. In fact, clusters contain stars formed more or less simultaneously from a single molecular cloud. This means that they represent coeval samples of stars with different masses, which allow

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Supernova explosions produced by LBV stars. The study: “Modeling the remnants of core-collapse supernovae from luminous blue variable stars” of S. Ustamujic (INAF-OAPA) recently appeared on Astronomy & Astrophysics

Ricerca

LBV (Luminous Blue Variable) stars are massive and unstable stars characterized by large mass-lost due to intense stellar winds and aperiodic bursts. Due to their instability, LBV stars are also variable, with quasi-periodic oscillations of their luminosity of the order of 0.5-2 magnitudes. Typical examples of this class of stars are: the supergiant S Doradus in the Large Magellanic Clouds,

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The nature of the binary system NGC1850-BH1 still debated: a system with a 11 solar masses black hole (Saracino et al. 2021) or with a sdOB star (El-Badry et al. 2021)?

Ricerca

In the last years several observational surveys were designed in order to detect stellar mass black holes, including both those which are actively accreting and black holes in a quiescent status. These observations are crucial to understand the real extent of the population of black holes in the Milky Way, and to understand the formation of massive stellar black holes

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Discovered the first planetary system with planets both in equatorial and polar orbits revealed by the study: “The Rossiter-McLaughlin effect revolutions: an ultra-short period planet and a warm mini-Neptune on perpendicular orbits” of V. Bourrier (Observatoire Astronomique de l’Université de Genève), appeared on A&A

Ricerca

The study of the architecture of planetary systems, and in particular that of the spin-orbit angle (which is the inclination of the planetary orbit with respect to the stellar rotation axis) can unveil important details on the dynamical evolution of planetary systems. In particular, young planets typically migrate radially, changing their distance to the host star and interacting with the

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The properties of the exoplanets sculpted by the forming environment. The study: “Exploring the link between star and planet formation with Ariel” of D. Turrini (INAF-IAPS) appeared on Experimental Astronomy

Ricerca

To date (October 2021, data from https://exoplanets.nasa.gov/), astronomer discovered enough exoplanets (in excess of 4500) to allow not only analysis of individual planets, but also detailed studies of the whole exoplanets population. These studies are necessary to fully understand the process of planets formation, the evolution of planets, the chemical composition and physical properties of planets atmospheres, and how the forming

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The study: “Estimating Magnetic Filling Factors from Simultaneous Spectroscopy and Photometry: Disentangling Spots, Plage, and Network” of T. W. Milbourne (Harvard University), recently appeared on ApJ, present two new methods that allow astronomers to estimate the filling factor of magnetic active regions

Ricerca

About 20% of the exoplanets discovered so far (October 2021) were found with measurements of radial velocity (data from https://exoplanets.nasa.gov/). This method is based on spectroscopic observations of stars with planets, from which it is possible to measure the Doppler effect produced by periodic oscillations of the star, due to the gravitational attraction between star and planet along the orbit of

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Published in A&A the paper describing the catalog of the candidate targets for the PLATO mission: “The all-sky PLATO input catalogue” of M. Montalto (Unipd/INAF-OAPd)

Ricerca

According to the data released by NASA, to date (2021 October 1st) we have confirmed 4525 exoplanets in 3357 planetary systems. The vast majority of these planets (75%) were discovered with the methods of transits, while about 20% with that of radial velocity. With the former technique, planets are discovered when they transit in front of their stars along our line

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