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The solar corona is a structure that extends for several solar radii and is filled with low-density plasma at temperatures of millions of degrees. What heats coronal plasma to such extreme temperatures? It appears to be a combination of complex magnetic phenomena.   X-ray and UV observations of the Sun reveal an atmosphere rich in bright structures that host million-degree

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The Caldera: a pulsar and a supernova remnant at the remarkable distance of 6500 light years from the Galactic plane, observed in the X-rays by XMM/Newton   In recent years, a few supernova remnants — rapidly expanding nebulae generated by stellar explosions — have been discovered at large distances from the Galactic plane. These objects have drawn significant interest for

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A new theoretical study shows that the holes in the structure observed by the James Webb Space Telescope called “Green Monster” within the Cassiopeia A (Cas A) supernova remnant is due to the interaction between a pre-existing layer of circumstellar material, impacted by the supernova shock wave, and elongated stellar fragments produced by hydrodynamic instabilities.   Supernova remnants are objects of

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To date, exoplanetary transits have allowed astronomers to discovery more than 70% of known exoplanets. Besides, by analysing stellar spectra acquired during the transits it is possible to study the atmospheres of the transiting exoplanet. During the transit, in fact, the planet is crossing the stellar disc, causing a small and periodic dimming of stellar observed flux. If the exoplanet

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Accretion is a ubiquitous phenomenon in the Universe, occurring over a wide rande of scales: From the small T Tauri stars to the enormous black holes in the center of galaxies. In particular, T Tauri stars are very young stars (a few million years old) still surrounded by a disk, called protoplanetary disk, and still acrreting gas from their disks.

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Stars more massive than 9 solar masses end their evolution in spectacular supernova explosions. These explosions are triggered by the gravitational collapse of the core of such massive stars, once the thermonuclear reactions are exhausted and the core is not supported against gravity by the pressure produced by the reactions. Supernovae are not simple spherical explosions, but rather complex phenomena

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