Grazie al progetto EWOCS, identificata per la prima volta la popolazione di oggetti sub-stellari di un superammasso stellare Attraversando il diagramma di Hertzsprung-Russell dalle masse maggiori a quelle minori, si incontrano stelle con struttura interna, proprietà ed evoluzione totalmente diverse. Il limite inferiore in termini di massa per una stella è di 0.075 masse solari: al di sotto di
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A new study on the low mass stellar population of the star forming region Corona Australis shed light on the formation of brown dwarfs In recent years, several studies of star-forming regions near the Sun have revealed that a significant fraction of the stellar population of the Milky Way consists of brown dwarfs—objects whose cores do not reach the
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Too small to be a star, too large to be a planet, Cha 1107-7626 is the smallest known isolated object (6–10 Jupiter masses) surrounded by a protoplanetary disk rich in gas and dust, which is still actively accreting gas and hosts organic molecules such as methane and ethylene. Brown dwarfs are fascinating objects that represent a bridge between stars
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Typically, planets did not form at the distance from their central stars where we observe them today. In fact, during their early evolution, planets migrate from their initial orbit until the system reaches its final configuration. Planetary migration can be induced by several processes: the interaction between the newborn planets and the protoplanetary disk where they formed, the gravitational interaction
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Nature sets a lower limit on stellar masses: objects less massive than 0.07-0.08 solar masses are incapable of initiating the thermonuclear reactions that power more massive stars. Below this threshold lies the realm of brown dwarfs, objects whose mass is too small to qualify as stars, yet too large to be categorized as planets. The mechanism responsible for the
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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
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