Absolute Magnitude
The brightness a star would have at a distance of 32.6 light-years from Earth.



Astronomer
A scientist who studies the universe (astronomy).



Black Hole
An object so massive and dense that even light cannot escape its gravity.



H-R Diagram
Hertzsprung-Russell diagram; a graph that shows the relationship between a star's surface temperature and absolute magnitude.



Main Sequence
The location on the H-R diagram where most of the stars are located.



Neutron Star
A star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons.



Pulsar
A rapidly spinning neutron star that emits rapid pulses of radio and optical energy.



Red Giant
A large, reddish star late in its life cycle.



Supernova
A gigantic explosion in which a massive star collapses and throws its outer layers into space.



White Dwarf

A small, hot, dim star that is the leftover center of an old star.