Sentences with phrase «seen white dwarf stars»
According to a report published today in the journal Nature, some of the emissions come from discrete sources representing hundreds of never - before - seen white dwarf stars, neutron stars and black holes.
https://www.scientificamerican.com/ Not exact matches
The study, «Accretion - induced variability links young stellar objects, white dwarfs, and black holes», which is published in the journal Science Advances, shows how the «flickering» in the visible brightness of young stellar objects (YSOs)-- very young stars in the final stages of formation — is similar to the flickering seen from black holes or white dwarfs as they violently pull matter from their surroundings in a process known as accretion.
Cruelly, the dense white dwarf star could also be headed for a violent demise unlike anything we've ever seen.
«Any metals we see in the white dwarf will disappear within a few weeks, and sink down into the interior, unless the debris is continuously flowing onto the star.
The result is an object having two distinct parts: a well - defined core of mostly carbon ash (a white dwarf star; see below End states of stars) and a swollen spherical shell of cooler and thinner matter spread over a volume roughly the size of the solar system.
«Our final image should show us a companion 100 times fainter than any other white dwarf orbiting a neutron star and about 10 times fainter than any known white dwarf, but we don't see a thing,» team member Bart Dunlap, a graduate student from the University of North Carolina at Chapel Hill, said in a statement.
«You can see bulges in distant galaxies, but you can not resolve the very faint stars, such as the white dwarfs.
HD 147513 A is a so - called young «Barium dwarf» (s - process element rich but comparatively carbon deficient) star that was probably enriched by an asymptotic branch giant (AGB) star (see Gacrux) but is now a very dim, white dwarf companion, which has an observed separation of around 4,400 AUs — 5.7» at a HIPPARCOS distance estimate of 42.0 ly (Porto de Mello and da Silva, 1997; and Poveda et al, 1993, pp. 74 - 75).
Such «barium stars» may be binaries, where a more massive companion has already thrown off its outer gas envelopes as a planetary nebula in becoming a white dwarf (see HD 147513 AB).