when a star inward gravity and outward pressure are balanced, the star is said to be
in a hydrostatic equilibrium
which of the follwoing elements contained in your body is NOT formed in the cotrd of stars during thermonuclear fusion
what inevitably forces a star like the sun to evolve away from being a main sequence star
helium builds up in the core, while the hydrogen burning shell expands
just as low-mass main sequence star runs out of fuel in its core, it actually becomes brighter...
the core contracts, rasing the temperature and increasing the size of the region of hydrogen shell burning
in the HR diagram steps labeled at which point on the graph does helium flash occur
the red giant branch (9)
which of these is true regarding planetary nebulae
some are spherical, but most have bipolar struccture
what is a planetary nebula
the ejected envelope, often bipolar , of a red giant surroundings a stellar core remenant
the order of evolutionary stages of a star like the sun would be Main sequence, giant, planetary nebula and finally
compared to our sun , a typical white dwarf is.....
about the same mass and a million times higher density
a high mass star dies more violently than a low mass star because...
it generate more heat and its core eventually collapses very suddendly
isolated main sequence stars as massive as 10-12 times the mass of the sun may still manage to avoid going supernova why?
because it can also have strong stellar winds
which describes the eveolutionary track on the HR diagram for the most massive stars
as a 4-10 solar mass star leaves the main sequence on its way to becoming a red supergiant, its luminosity
remains roughly constant
in the evolution of massive stars, what is th esignificance of the temperature 600 million kelvin
it is the temperature need for carbon fusing into heavier elements
compared to a cluster containing type O and B stars, a cluster with only type F and cooler stars will be..
in a fairly young star cluster, if the most massive star are swelling up into giants, the least massive star are
still evolving toward their ZAMS positions
which is used obsevationally to dtermine the age of a star cluster
the luminosity of the main sequence turnoff point
the roche lobe of a star in a binary star system...
in, in terms of the star's gravity its "zone of influence"
the most famous case of a massive hot star orbiting a more evolved but presently less massive red giant is the eclipsing binary,...
that brighter sirius A weighs 3 solar masses, but the white dwarf sirius B is only about one solar mass implies
that the collapsed companion transfered mass to sirius A
you observed a low mass helium white dwarf, what can you conclude
it is part of a binary star system