Semester Finals Flashcards
Orbit
The curved path of a celestial object or spacecraft around a star planet or moon.
Solar system
The gravitationally bound planetary system of the sun and the objects that orbit it either directly or indirectly of the objects that orbit the sun directly the largest are the eight planets .
galaxy
A system of millions or billions of stars together with gas and dust held together by gravitational attraction.
Universe
All of space and time and their contents including planets stars galaxies and all other forms of matter and energy
Satellite
A artificial object which has been intentionally placed into orbit.
Impact crater
A crater on a planet or moon caused by the impact of a meteorite or other object typically circular with a raised rim
Rotation
A action of rotating around an axis or center
Revolution
A forcible overthrown of a government or social order in favor of a new system
Season
Each of the four divisions of the year spring, summer , autumn, and winter
Equinox
The time or date at which the sun crosses the celestial equator when day and night are of equal length
Solstice
When the sun reaches its highest or lowest point in the sky at noon marked by the longest and shortest days
Mare
A large level basalt plain on the surface of the moon appearing dark by contrast with highland areas
Eclipse
Either of the two points on the celestial sphere where the celestial equator interacts the ecliptic
Umbra
The dark central part of a sunspot
Penumbra
The shadow cast by earth or moon over an area experiencing a partial eclipse.
The less darker outer spot of a sunspot surrounding the dark core
Astronomical unit
A u it of measurement equal to 149.6 million kilometers the mean distance from the center of the earth to the center of the sun
Ellipse
A regular oval shape traced by a point moving in a plane so that the sum of its distances from two other points is constant
Terrestrial planet
A planet that is composed primarily of silicate rocks or metals
Gas giant
A large planet of relatively low density consisting predominantly of hydrogen and helium such as Jupiter Saturn Uranus Or Neptune
Asteroid
Minor planets especially of the inner solar system
Comet
An icy small solar system body that when passing close to the sun warms and begins to release gases
Meteor
A small body of matter from outer space that enters the earths atmosphere becoming incandescent as a result of friction and appearing as a streak of light
Meteorite
A solid piece of debris from an object such as a comet , asteroid , or meteoroid that originates in outer space and survives its passage through the atmosphere
Geocentric
Measured from or considered in relation to the center of the earth
