Category: Ricerca

Nanoflares and the heating of solar corona. The study: “Statistical Signatures of Nanoflare Activity. I. Monte Carlo Simulations and Parameter-space Exploration” of D. B. Jess (Queen’s University Belfast) recently appeared on ApJ.

Ricerca

There are still secrets of our Sun that the scientific community struggles to unveil. One of this is the mechanism responsible for the heating of solar corona. While the photospheric plasma has a typical temperature of about 5700 degrees, in fact, the plasma in the solar chromosphere and corona is hotter: about 10000 degrees in the chromosphere and 1-2 millions

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31 years of evolution of a supernova remnant. The study: “3D MHD modeling of the expanding remnant of SN 1987A. Role of magnetic field and non-thermal radio emission” of S. Orlando (INAF-OAPA) recently published by A&A

Ricerca

During the 1987 February 23rd night, astronomers observed the explosion of a supernova in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. The exploded star was the blue supergiant Sanduleak (Sk) − 69o202, with a mass of 20 solar masses, and its explosion produced the supernova remnant SN 1987A. From that moment, SN 1987A was observed with

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Three super-Earth for a star. The study “Masses and radii for the three super-Earths orbiting GJ 9827, and implications for the composition of small exoplanets” of K. Rice (University of Edinburgh) published by MNRAS

Ricerca

Super-Earths are exoplanets with radii between that of the Earth and that of Neptune (about 4 times the radius of the Earth), and with orbital periods smaller than 100 days. Although the Solar System does not host a similar planet, super-Earths are actually common in the Milky Way. This type of exoplanet is also interesting since they populate a gap

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Giants planets and stellar metallicity. The study “The GAPS Programme with HARPS-N at TNG XVIII. Two new giant planets around the metal-poor stars HD 220197 and HD 233832” of D. Barbato (UNITO/INAF-OATO) published by A&A

Ricerca

One of the products of the star formation process are disks of gas and dust that orbit young stars during their early evolution, being dispersed by several mechanisms in less than 10 million years. These disks are called “protoplanetary disks”, since they are the structures that may evolve in planetary systems. Planet formation is a complex process that involve several

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Shock e riscaldamento degli ioni in ambienti astrofisici. Pubblicato su Nature Astronomy lo studio “Collisionless shock heating of heavy ions in SN 1987A” di M. Miceli (UNIPA/OAPA)

Ricerca

Gli shock sono onde d’urto che viaggiano a velocità supersonica e sono molto importanti in astrofisica perché vengono osservati su diverse scale spaziali ed in diversi contesti, dal nostro “piccolo” sistema solare, fino a scale extragalattiche e cosmologiche. Gli shock astrofisici differiscono da quelli osservabili sulla Terra perché si manifestano in condizioni estreme, non riproducibili sul nostro pianeta.  Mentre nell’atmosfera

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Two LSST white paper are led by INAF-OAPA astronomers

Ricerca

LSST (Large Synoptic Survey Telescope) is the future of the astronomy in the time domain. LSST is a new-generation telescope that will be built on Cerro Pachon in Chile (2700 meters). It will be equipped with a primary mirror of 8.4 meters of diameter and an innovative camera able to observe an very large field of view, more than 49

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Multi-band observations of stellar flares. the study: “A multi-wavelength view of magnetic flaring from PMS stars” of E. Flaccomio (Inaf – OAPA) recently published by A&A

Ricerca

Most of the stars, mainly the low mass stars, produce their own magnetic field in their interior. The interaction between the magnetic field and stellar plasma is the cause of phenomena such as photosperic spots, faculae, protuberances, coronal mass ejections, and flares. The study of this activity is important both because it reveals how intense magnetic fields interact with high-temperature

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Radiation and abundances of organic compounds in planets-forming disks. The study: “X-Ray Photo-desorption of H2O:CO:NH3 Circumstellar Ice Analogs: Gas-phase Enrichment” of A. Jiménez-Escobar (Inaf-OAPA) published in ApJ

Ricerca

From the large number of exoplanets discovered by missions such as Kepler and CoRoT, it is clear that the presence of planets is a common feature in stars of our Galaxy. In particular, it has been estimated that on average each low mass star has one planet. Planets formation is thus an ubiquitous phenomenon across the Milky Way. It is

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