Filaments in Cas A probe the processes occurred inside the progenitor during the explosion. The paper: “Filamentary ejecta network in Cassiopeia A reveals fingerprints of the supernova explosion mechanism” of S. Orlando (INAF-OAPA) appeared on A&A

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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A green monster inside Cas A unveils the secrets of its violent phenomena. The study: “The Green Monster Hiding in Front of Cas A: JWST Reveals a Dense and Dusty Circumstellar Structure Pockmarked by Ejecta Interactions” of I. de Looze (Ghent University) recently appeared on ApJL

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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The properties of the reverse shock in Cas A reveal properties of the progenitor. The paper: “Evidence for past interaction with an asymmetric circumstellar shell in the young SNR Cassiopeia A” of S. Orlando (INAF – OAPA) recently appeared on A&A

Supernova remnants (expanding clouds produced by the explosion of massive stars) are fascinating objects. Their study, in fact, can unveil the physical processes working during supernova explosions and even the properties of the stellar progenitors. To these aims, of particular importance is the analysis of the physical and chemical properties of the ejecta (which are the fragments of the dying

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A new diagnostic tool to identify metal-rich ejects in supernova remnants. The study: “Unveiling pure-metal ejecta X-ray emission in supernova remnants through their radiative recombination continuum” of E. Greco (UNIPA/INAF-OAPA/API) recently appeared on A&A

Supernova remnants are nebulae created by supernova explosions. These expanding clouds are formed by the interstellar medium shocked and heated up by the expanding shock produced by the explosion, and the knots of material launched by the exploding star, called ejecta. These ejecta are located behind the expanding shock, traveling with lower velocity, and they are heated up by the reverse shock:

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