Solar Seystem Flashcards
Orbit
repeating path that one object in space takes around another one
Crescent moon
a curved shape that is wider in the middle than at its ends
Revolution
a complete, 360-degree turn or rotation
Gravity
A body that attracts other ones
Wanning
Unnaturally pale
Meteor
A streak of light
Quarter moon
The moon is a quarter lit
Comet
a celestial object consisting of a nucleus of ice and dust
Galaxy
a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity
Season
a single, dominant repeating pattern of fixed frequency
Heliocentric
having or representing the sun as the center, as in the accepted astronomical model of the solar system
terrestrial planet
Earth-like planets made up of rocks or metals with a hard surface
Meteor
a small body of matter from outer space that enters the earth’s atmosphere, becoming incandescent as a result of friction and appearing as a streak of light
Equinox
the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length
Geocentric
having or representing the earth as the center, as in former astronomical systems
Astronomical Unit
a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun
Full Moon
an object that orbits a planet or another celestial body that is not a star
Eclipse
occurs when one heavenly body such as a moon or planet moves into the shadow of another heavenly body
Tide
very long-period waves that move through the ocean in response to the forces exerted by the moon and sun
Asteroid
a small rocky body orbiting the sun. Large numbers of these, ranging in size from nearly 600 miles
Waxing
increasing, or becoming larger in size
Quarter Moon
When half of the Moon’s disc is illuminated
Umbra
that part of a shadow in which all light from a given source is excluded
Penumbra
space of partial illumination (as in an eclipse) between the perfect shadow on all sides and the full light