Low-mass supergiant that is almost devoid of hydrogen
An extreme helium star (abbreviated EHe) is a low-mass supergiant that is almost devoid of hydrogen, the most common chemical element of the Universe. Since there are no known conditions where stars devoid of hydrogen can be formed from molecular clouds, it is theorized that they are the product of the mergers of helium-core and carbon-oxygen core white dwarfs.
and 24 Related for: Extreme helium star information
envelope phase. It is believed this is the origin of the extremehelium stars. The heliumstar's great capability of transforming into other stellar objects...
white dwarfs: PV Telescopii, also known as HD 168476, is a hot blue extremeheliumstar, while RS Telescopii is an R Coronae Borealis variable. RR Telescopii...
than normal for a star of stellar class B, while the lines of helium and carbon are stronger. They are a type of extremeheliumstar. The prototype for...
A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of...
In astronomy, the term compact object (or compact star) refers collectively to white dwarfs, neutron stars, and black holes. It could also include exotic...
refer to: Epithelioid hemangioendothelioma, a type of tumor Extremeheliumstar, a type of star Elective home education, a form of education Marriage (1929...
atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen...
Popper's Star and V821 Centauri, is an extremeheliumstar in the Centaurus constellation. Discovered by astronomer Daniel Popper, this star has a spectral...
about 90% helium and less than 1% hydrogen. The majority of the remainder is carbon. This classifies it as a carbon-enhanced extremeheliumstar. Modelling...
evolution and eventual fate. A star shines for most of its active life due to the thermonuclear fusion of hydrogen into helium in its core. This process releases...
hydrogen into helium in a shell surrounding an inert helium core red-clump stars in the cool half of the horizontal branch, fusing helium into carbon in...
as extreme horizontal branch, have temperatures of 20,000–30,000 K. This is far beyond what would be expected for a normal core helium burning star. Theories...
mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron. The Sun is a G-type main-sequence star (G2V)...
dredge-ups during shell burning, and to the loss of the outer layers of the star. Helium is formed in the core and shell by fusion of hydrogen and nitrogen which...
so that the helium fusion ceases, and the hydrogen shell burning restarts. During these shell helium flashes, the mass loss from the star is significant...
Variable Star Observers. Retrieved 24 January 2014. Woolf, V. M.; Jeffery, C. S. (2002). "Temperature and gravity of the pulsating extremeheliumstar LSS...
of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime...
helium, qualifying it as an extremeheliumstar. Its origin is unclear, but thought to be a result of the merger of a helium white dwarf with a carbon/oxygen...
−169 km/s. This is an extremeheliumstar that shows a highly-processed atmosphere. It is a blue-white hued B-type supergiant star with a peculiar spectrum...
approximately 3×108 K, helium burning (fusion of helium nuclei) begins. The onset of helium burning in the core halts the star's cooling and increase in...
DB – a helium-rich atmosphere, indicated by neutral helium, He I, spectral lines. DO – a helium-rich atmosphere, indicated by ionized helium, He II,...
6. When the core helium is exhausted, a star with up to about 8 M☉ has a carbon–oxygen core that becomes degenerate and starts helium burning in a shell...
Global Information