Ch. 30 Sections 1 and 2 Flashcards
Star
A large celestial body that is composed of gas and that emits light.
Doppler effect
an observed change in the frequency of a wave when the source or observer is moving.
Light-year
The distance that light travels in one year.
Parallax
An apparent shift in the position of an object when viewed from different locations.
Apparent Magnitude
The brightness of a star as seen from the Earth
Absolute Magnitude
The brightness that a star would have at a distance of 32.6 light-years from earth.
Main Sequence
The location on the H-R diagram where most stars lie; it has a diagonal pattern from the lower right to the upper left
Nebula
A large cloud of gas and dust in interstellar space; a region in space where stars are born
Giant
a very large and bright star whose hot core has used most of its hydrogen
White Dwarf
a small, hot dim star that is the leftover of an old star
Nova
a star that suddenly becomes brighter
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 tat emits pulses of radio and optical energy
Black hole
An object so massive and dense that even light cannot escape its gravity.
Constellation
One of 88 regions into which the sky has been divided in order to describe the locations of celestial objects; a group of stars organized in a recognizable.
