Several stellar phenomena and evolutionary processes are connected to their magnetic fields. The mechanisms that allow stars to produce their magnetic fields depend on their internal structure and stellar properties. One dominant property is stellar rotation: the faster stars rotate, the more intense their magnetic field and magnetic activity. Since stellar rotation declines with age, it is not surprising that
After the Big Bang, the Universe contained only hydrogen, helium, and a very small fraction of lithium. After that, stars, mainly the most massive ones, were responsible for the chemical enrichment of the Universe. In fact, stars produce energy by synthetizing chemical elements in their cores. These elements are then redistributed in the interstellar medium when stars end their evolution.
di Mario Giuseppe Guarcello ( follow mguarce) Type Ia supernovae are particularly important in cosmology since they allow us precise measurements of the hosting galaxies. These supernovae are not triggered by the collapse of the core of massive stars, such as the “core-collapse supernovae”. They are instead due to the thermonuclear explosion of a white dwarf in close binary
L’astronoma Beate Stelzer dell’Osservatorio Astronomico di Palermo è autrice dell’articolo “X-ray orbital modulation of a white dwarf accreting from an L dwarf” pubblicato su Astronomy & Astrophysics. Nell’articolo sono analizzati i dati ai raggi X ottenuti da osservazioni con il satellite XMM/Newton del sistema binario SDSS J121209.31+013627.7, composto da una nana bianca ed una nana bruna. Nello studio è riportata la
