The James Webb Space Telescope, the flagship observatory of NASA/ESA/CSA, has turned its gaze toward the supernova remnant SN 1987A, revealing its structure with an unprecedented level of detail. About 400 years after Kepler supernova, which exploded in 1604, the skies of the southern hemisphere witnessed another supernova relatively close to us. This was SN 1987A, which exploded on
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A new theoretical study shows that the filamentary structure observed in the supernova remnant Cassiopeia A (Cas A) is a direct consequence of the processes that occurred in the progenitor star immediately after core collapse. Supernovae are among the most energetic explosive events in the Universe. Yet, despite their immense brightness, they convert only about 1% of their energy
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Analysis of X-ray observations of the SN1987A supernova remnant, obtained by the XMM-Newton satellite, provides new insights into the interaction between the supernova shock wave and the circumstellar material, as well as the oxygen abundance in the remnant. The SN1987A supernova remnant is undoubtedly one of the most iconic objects for studying supernovae, their remnants, and the final stages
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There are many lessons about the physics of supernova remnants and progenitor stars that the Cassiopeia A (Cas A) supernova remnant teaches us. For example, we have learned that both the supernova explosion and the mass-loss episodes that characterize the final evolutionary stages of the progenitor star can be highly asymmetric. We have come to understand that supernovae can play
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Supernova remnants serve as unique laboratories to understand the complex processes occurring during a supernova explosion and to investigate the internal structure of massive stars just before their explosive demise. Additionally, the study of these remnants is driven by their crucial role in accelerating cosmic rays, which are particles with extremely high energies. In 1949, Enrico Fermi laid the groundwork for
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The role of supernova remnants (expanding clouds produced by supernovae) in the acceleration of cosmic rays (high-energy particles present in various astrophysical environments) has been known since 1995. The discovery, made by astronomers from Kyoto University, was made possible by identifying the presence of non-thermal X-ray emission in the supernova remnant SN 1006. X-rays are a type of high-energy radiation
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Our planet is constantly bombarded by highly energetic particles known as ‘cosmic rays‘. The spectrum of cosmic rays up to energies of 1015 electronvolts (eV) is formed by the sources in our Galaxy, while particles with observed energies up to 1021 eV should have extra-galactic origin. The cosmic ray spectrum follows a power law, meaning that the flux of particles with a given
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Supernova remnants, which are nebulae produced by explosion of supernovae and undergoing rapid expansion, typically serve as intense sources of high-energy radiation, particularly in the form of X-ray emissions. This radiation can be of two different types: thermal and non-thermal. Thermal radiation is emitted by dense material and is contingent upon the temperature of the emitting gas. To emit X-rays,
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SN1987 A is one of the most significant objects for studying supernova explosions and their remnants. This is because it is the only core-collapse supernova that has occurred relatively close to us (approximately 170000 light-years away, in the Large Magellanic Cloud) in the modern epoch. Therefore, it is the sole object of this type for which we have telescope observations
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Supernova remnants are expanding nebulae produced by the explosion of high-mass stars. They are of great interest for understanding various physical processes and the final evolutionary stages of massive stars. Observations of supernova remnants in gamma rays are particularly important as they shed light on high-energy processes, such as the acceleration of cosmic rays (charged particles at very high energies).
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