an imaginary pattern of stars.
an instrument that separates light into colors and makes an image of the resulting spectrum
the brightness of star as seen on Earth
a brightness a star would have if it were at a standard distance from earth
the distance light travels in 1 year, about 9.5 million mllion kilometers
the apparent change in position of an object when seen from different places.
a graph relating the surfaces temperatures and absolute brightnesses of stars.
a diagonal area on an H-R diagram that includes more than 90 percent of all stars.
a large cloud of gas and dust in space, spread out in an immense volume.
a crontacting cloud of gas and dust with enough mass to form a star.
the blue-white hot core of a star that is, left behind after its outer layers have expanded and drifted out in space.
the brilliant explosion of a supergiant star.
the small, dense remains of a high-mass star after a supernova.
a rapidly spinning neutron star that produces radio waves.
an object whose gravity is so strong that nothing, not even light, can escape.