A large, glowing ball of gas in space, which generates energy through nuclear fusion in its core.
The distance that light travels in a vacuum in a year.
The apparent change in position of an object with respect to a distant background.
The brightness of a star as it appears from Earth.
How bright a star really is.
A set of dark lines that show where light has been absorbed.
A graph of the surface temperature, or color, and absolute brightness of a sample of stars.
The diagonal band on an H-R diagram.
Very bright stars located at the upper right of the H-R diagram.
Large, bright stars that are smaller and fainter than supergiants.
The small, dense remains of a low-mass or medium-mass star.