Universe vocab Flashcards
A brightness scale used to measure of how bright a star would be if it were seen form a standard distance.
Absolute magnitude
the brightness of a star as seen from Earth.
Apparent magnitude
a large collection of stars, dust, and gas bound together by gravity.
galaxy
Hertzsprung-Russel diagram, a graph that shows the relationship between a star’s surface temperature and absolute magnitude.
H-R Diagram
The distance that light travels through space in one year; about 9.46 trillion kilometers.
Light-year
the actual brightness of an object such as a star.
Luminosity
the region on the H-R diagram where stars spend most of their lives; it has a diagonal pattern.
Main sequence
a large cloud of dust and gas in interstellar space; a region in space where stars are born.
nebula
a core of a supernova that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons
neutron star
a relatively large spherical body that orbits a star
planet
a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation.
Pulsar
the motion of a body that travels around another body in space; one trip along an orbit.
revolution
a spin of a body on its axis
rotation
a collection of large and small bodies that orbit our central star, the sun
solar system
a large celestial body that is composed of gas that emits light; the sun is a typical star
star
the distance between two adjacent troughs or crests of a wave
wavelength
a gigantic explosion in which a massive star throws its outer layers into space, but it’s core remains.
supernova
space and all the matter and energy in it
universe
the hot, dense, dim core of matter that remains from the collapse of a low mass star.
white dwarf
a galaxy shaped like a pinwheel, with a bulge in the center and spiral arms extending outwards.
spiral galaxy
a spherical or elongated galaxy with a bright center and very little dust and gas
elliptical galaxy
a galaxy with an irregular shape that does not fit into any other category.
irregular galaxy
all of the different wavelengths and frequencies or electromagnetic radiation, from radio waves to gamma rays.
electromagnetic spectrum
the theory that all matter and energy in the universe was compressed into an extremely small volume that 13 billion to 15 billion years ago exploded and began expanding in all directions.
big bang theory
