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Solar corona is made of plasma at million degrees. The mechanism responsible for the heating of the corona, which is the outer part of the solar atmosphere, is still one of the unsolved problems of solar physics. For comparison, the plasma in the photosphere is on average at about 5600 degrees. It is widely accepted that the responsible for heating

The final architecture of a planetary system is the result of a complex interplay between several processes, such as the dispersion of the protoplanetary disk from which the planetary system formed, and the gravitational interaction between the newborn planets. Besides, these processes can be affected by the environment and by their central star. One of the most important process dictating

Pre-Main Sequence stars are young (few million years) stars whose nuclei are not powered yet by the thermonuclear reactions, and that may still accrete gas from a surrounding disk (called protoplanetary or accretion disks). Even if the accretion disks are typically extended more than 100 Astronomical Units (AU, the mean distance between Earth and the Sun, equal to 150 million

The Solar corona is visible in the energetic bands of the electromagnetic spectrum as composed by magnetic arcs filled by plasma at million degrees, which are particularly bright in the active regions. Despite it is clear that the magnetic field plays a fundamental role in heating and confining the plasma, the Solar corona is still a complex region where energetic

Pre-Main Sequence stars are young stars whose cores are not dense and hot enough to ignite the thermonuclear reactions that will power them for the rest of their evolution. These stars are sorted in three classes: the youngest stars are the class I sources, still embedded in an accreting envelope of gas; class II stars have dispersed their accreting envelope

Stellar magnetic activity results from the interaction between stellar magnetic field and the plasma in photosphere, chromosphere, and corona. This activity produces well known phenomena, such as flares, spots, faculae, and prominences, observed in stars of almost every type and mass. This activity is typically studied by analyzing spectroscopic activity indicators produced by these phenomena, such as the H and

In the last years, several organic molecules, some of which of prebiotic interest, have been observed in different astronomical environments. For instance, Acetonitrile CH3CN was detected in the molecular cloud Sag B2 and in the protostar MWC480; formamide (a building block for sugars and amino-acids) was detected in some outer galaxies and in the protostar SVS13-A (in this case together

The Sun has an intense magnetic activity which produces transient phenomena such as flares, coronal mass ejections (CMEs), sunspots, etc…, with CMEs being the most energetic phenomena associated with the solar magnetic activity. CMEs consist in rapid ejections of coronal plasma, which are triggered by the recombination of the magnetic field lines that also produce solar flares. During solar flares,

The stellar magnetic activity can produce an important emission of energetic X-ray and UV radiation. This emission is typically variable, both because the magnetic activity changes over short time scales, and because it decreases during stellar evolution. For instance, solar-type stars in the pre-main sequence phase (i.e. younger than 30 million years) are thousand times brighter in X-rays than main

T Tauri stars are young (typically younger than 10 million years) stars surrounded by a protoplanetary disk, which is a disk of gas and dust orbiting around the star and that eventually can evolve in planetary systems. Despite these stars have already accreted most of their mass, they can still accrete some mass from their protoplanetary disks. The accretion process