SN1987A, the supernova exploded in the Large Magellanic Cloud (at about 170000 light years of distance) on February 23rd 1987, was an iconic event for the study of supernovae and supernova remnants. In fact, it is the only case where it was possible to observe (with telescopes) the explosion and to follow with periodic observations the evolution of the supernova
Stars are variable sources over timescales which depend on the phenomena triggering this variability. These phenomena are typically produced by the interaction between the stellar magnetic field and its plasma. Typical examples, observed and studied in great details in the Sun, are: flares (sudden release of a large amount of energy by the magnetic field which heats the gas in
The corona is the outermost part of the atmosphere in stars with intermediate and low mass. In this region, which is extended for several stellar radii, the plasma can reach temperatures of several million degrees, emitting mainly X-ray radiation. The coronal temperature varies over a range of several orders of magnitude as a function of several stellar parameters, such as
Star clusters are a product of the star formation process. During their gravitational collapse, in fact, molecular clouds fragment forming hundreds or even thousands of stars. During the first few tens of million of years of their evolution, the young stars formed in a cloud are bound by the intense mutual gravitational attraction, forming a stellar cluster. Star clusters are important
Star clusters contain a rich population of stars covering a wide range of stellar masses (sometimes from the brown dwarfs to massive stars) with a well defined age. For this reason, star clusters represent fundamental targets to test the theoretical models describing stellar physics and evolution. However, this requires precise measurement of stellar clusters age. The method which is commonly
A supernova is the final act of the evolution of a massive star. These spectacular explosions are among the most energetic events we observe in the Universe, and they can seriously impact the surrounding environment. In particular, during the expansions of the supernova remnants, which are the expanding clouds produced by supernova explosions, the process of star formation in the
There are still several secrets about the Solar corona that astronomers must unveil. The corona is the uppermost solar atmosphere, made by low-density gas with temperatures as high as a few million degrees (as a comparison, the plasma in photosphere and chromosphere is at about 5600 K and 10000 K, respectively). The energy required to heat the gas up to
The search for young exoplanets is crucial to our understanding of the planetary formation process and the early evolution of planets. The disc of gas and dust from which planets form, in fact, typically disperse in a few million of years. Before that, the young planets interact with all the material orbiting around the star within the disk, triggering important
Since the discovery of the first planet orbiting another star (51 Pegasi b, discovered in 1995), it has always been one of the main objective of the exoplanetary science to discover an Earth sibling. Such a planet must have a mass similar to that of the Earth, and it must orbit around its star in the “habitability zone”, which is
The “4-metre Multi-Object Spectroscopic Telescope” (4MOST) certainly is among those instruments that will play an important role in the next future of astronomy. 4MOST is a multi-object spectrograph capable of acquiring more than 2400 spectra simultaneously and observe a very large field of 4 square degrees. This is possible thanks to a complex system of optical fibers which can be
