X-rays from SN1987A: shocks, circumstellar clouds and ionised oxygen described in two recent publications

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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A system of super-Earth exoplanets orbiting around GJ 3998 described in the paper: “HADES RV Programme with HARPS-N at TNG XVI. A super-Earth in the habitable zone of the GJ 3998 multi-planet system” of A. K. Stefanov (IAC)

At just 60 light-years away from us, the M-type star GJ 3998 hosts a system of three super-Earths, discovered and studied thanks to observations from the Telescopio Nazionale Galileo.   M-type stars are among the most important targets in the search for exoplanets, primarily for two reasons: they are the most numerous stars in our Galaxy, and the most commonly

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Published the manifesto of the international task force for the study of environmental effects on the evolution of protoplanetary disks

Protoplanetary disks are structures of gas and dust that orbit around newly formed stars (referred to as both pre-main-sequence stars and protostars) during their very early evolutionary stages. In fact, they generally disperse in less than 10 million years. Despite their short lifespan, protoplanetary disks play a crucial role. From the perspective of the star, for example, these disks mediate

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Two hot Jupiters with a water-rich atmosphere. The study: “The GAPS Programme at TNG LXVII. Detection of water and preliminary characterisation of the atmospheres of the two hot Jupiters KELT-8 b and KELT-23 Ab” of M. Basilicata (University of Tor Vergata) appeared su A&A)

Observations carried out with the Telescopio Nazionale Galileo of two exoplanets belonging to the hot Jupiter class reveal an atmosphere rich in water, despite the high temperatures.   Water is an essential ingredient for life as we know it—not only because we drink it, but because it is an exceptional solvent for the chemical processes that underlie life on Earth.

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The relation between stellar metallicity and presence of giant planets in intermediate massive stars described in the study: “Intermediate-mass stars and the origin of the gas-giant planet-metallicity correlation” of J. Maldonado (INAF-OAPA)

As of today (February 2025), out of the 5834 identified exoplanets, only about 5% orbit stars with masses between 1.5 and 3.5 solar masses (intermediate-mass stars). This is likely due to specific difficulties in exoplanet detection techniques, difficulties that are not encountered for lower-mass stars. For example, since they are more luminous than lower-mass stars, the transit depth (i.e., the

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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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A sub-neptunian “dynamically hot” orbiting around the star BD+00 444 confirmed with HARPS-N observations.

An intriguing result, obtained thanks to the observational campaign carried out with NASA’s Kepler satellite, is that the most common transiting exoplanets are small planets with a radius smaller than 4 Earth radii and a short orbital period (less than 100 days). In particular, the most frequent planets belong to the sub-Neptune and super-Earth classes, two categories absent in the

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First direct detection of relativistic particles accelerated in shocks in the heliosphere described in the study: “Direct Measurements of Synchrotron-emitting Electrons at Near-Sun Shocks” of I. C. Jebaraj (University of Turku)

In the Universe, various environments are characterized by shocks capable of converting the kinetic energy of gas and particle flows into heat, turbulence, magnetic energy, and, ultimately, accelerating particles to relativistic energies, producing cosmic rays. The sizes of these systems can vary by many orders of magnitude, ranging from the typical dimensions of the interplanetary environment to the enormous galaxy

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Two mini-Neptuns in orbital resonance around TOI-1803 discovered and described in the paper: “A joint effort to discover and characterize two resonant mini Neptunes around TOI-1803 with TESS, HARPS-N and CHEOPS” of T. Zingales (UniPd/INAF-OAPd))

With over 2.600 exoplanets discovered, NASA’s Kepler satellite holds the record for the mission with the highest number of exoplanets found. The Kepler mission continued with the Kepler/K2 extension, redefined after technical failures prevented the telescope from maintaining its pointing. Among the many discoveries made possible by Kepler/K2 is evidence that one of the most common types of planets in

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The stellar surface trated as a puzzle. The study: “PAStar: a model for stellar surface from the Sun to active stars” of A. Petralia (INAF – OAPA) appeared on A&A

In stars, a continuous tug-of-war unfolds between stellar plasma and the magnetic field. At stake is control over the local dynamics: the winner sets the rules that govern the local stellar properties. For instance, the photosphere of stars is generally quite homogeneous, except for granulation. However, in certain regions of the photosphere, the magnetic field can concentrate, intensify, and produce

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