Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account


a large cloud of dust and gas in interstellar space; the location of star formation


the force of attraction between all masses in the universe


a typical star that is the source of light and heat for the planets in the solar system

solar nebula

a rotating cloud of gas and dust from which the sun and planets formed; also any nebula from which stars and planets may form

nebular theory

theory that the sun and the planets condensed out of a spinning cloud of gas and dust

condensation theory

Premise that stars and planets accumulated from contracting, accreting clouds of galactic gas, dust, and debris.

condensation nuclei

microscopic platforms to which other atoms can attach.


the formation of a celestial object by the effect of gravity pulling together surrounding objects and gases


Regions of condensed matter that serve as a starting point for the formation of a planet.


The depression at the summit of a volcano, or that which is produced by a meteorite impact

synchronous orbit

the state when period of rotation is exactly equal to orbital period. the moon is in this and thus presents the same face toward the earth at all times.

intercrater plains

the relatively smooth terrain on Mercury


planet closest to the Sun; has a thin atmosphere with temperature extremes, an iron core, and many craters and high cliffs


models of the universe based on the assumption that the sun, moon, and planets all orbit Earth


a model of the solar system in which Earth and the other planets revolve around the sun

interstellar dust

small particles or grains of matter, primarily carbon and silicates, distributed throughout interstellar space

jovian planets

the large, outer planets made of gas - Jupiter, Saturn, Uranus, & Neptune

terrestrial planets

Mercury, Venus, Earth, and Mars. They all have rocky crusts and dense mantles and cores.


any natural satellite of a planet


of or relating to or caused by meteorites

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording