Stellar Nursery: Large cold clouds of dust and gas where stars form.
Protostars: The stage in the formation of a star just before nuclear reactions ignite.
Brown Dwarf: An object with a mass less than about 8% of the mass of the Sun, but about 10 times greater than that of Jupiter.
Red Dwarf: A star with a mass between about 8% and 50% the mass of the Sun.
Sun-Like STAR: A star with mass between about 50% and 10 times that of the Sun.
Blue Supergiants: Stars much more massive than the Sun.
Red Giant: A phase in the evolution of a star after nuclear fusion reactions that convert hydrogen to helium have consumed all the hydrogen in the core of the star, and energy generated by hydrogen fusion in the shell causes the star’s diameter to greatly expand and cool.
Blue Giant: After a massive red giant star ejects its outer layers, its hot inner core is exposed, and it becomes a blue giant star.
Planetary Nebula: A nebula produced after an exhausted giant star puffs off its outer layer and leaves behind a smaller, hot star.
White Dwarf: The end phase of a Sun-like star in which all the material contained in the star, minus the amount blown off in the red giant phase, is packed into a volume one millionth the size of the original star.
Neutron Star: An extremely compact star produced by the collapse of the core of a massive star in the supernova process.
Blackholes: If the core of a collapsing star has a mass that is greater than three Suns, no known force can prevent it from forming a black hole.
Type Ia Supernova: An explosion produced when a white dwarf becomes unstable due to the accretion of too much material or merger with another white dwarf.
Type II Supernova: A supernova that occurs when a massive star has used up its nuclear fuel and its core collapses to form either a neutron star or a black hole, triggering an explosion.
Pair-instability Supernova: A rare type of explosion predicted to occur as a consequence of the extremely high temperatures in the interiors of stars having masses of about 200 suns.
Supershells: The combined activity of many stellar winds and supernovas create expanding supershells that can trigger the collapse of clouds of dust and gas to form new generations of stars.
End phases: A star’s ultimate fate depends on its mass. It can fade into obscurity (brown dwarf or red dwarf), become a white dwarf (sun-like stars), explode as a supernova and leave behind a neutron star or a black hole (massive to very massive stars), or be disrupted entirely (white dwarfs in close binary systems, or extremely massive stars).