Space Science Vocabulary Flashcards
The sun and its family of orbiting planets, moons and other objects.
Solar system
Millions or billions of stars held together in a group by their own gravity.
Galaxy
Space and all the matter and energy in it.
Universe
An object that orbits a more massive object.
Satellite
A round pit left behind on the surface of a planet or other body in space after a smaller object strikes the surface.
Impact crater
An imaginary line about which a turning body, such as Earth rotates.
Axis of rotation
The motion of one body around another, such as Earth in its orbit around the sun; the time it takes to go around once.
Revolution
One part of a pattern of temperature changes and other weather trends over the course of a year. Astronomical seasons are defined and caused by the position of Earth’s axis relative to the direction of sunlight.
Season
In an orbit, a position and time in which sunlight shines equally on the Northern Hemisphere and the Southern Hemisphere; a time of year when daylight and darkness are nearly equal for most of the Earth.
Equinox
In an orbit, a position and time during which one Hemisphere gets its maximum area of sunlight, while the other Hemisphere gets its minimum amount; the time of year when days are eather longest or shortest, and the angle of sunlight reaches its maximum or minimum.
Solstice
A large, dark plain of solidified lava on the Moon. The plural form of Mare, is Maria.
Mare
An event during which one object in space casts a shadow onto another. On Earth, a lunar eclipse occurs when the Moon moves through Earth’s shadow, and a solar eclipse occurs when the Moon’s shadow crosses Earth.
Eclipse
The dark, central region of a shadow, such as the cone of complete shadow cast by an object.
Umbra
A region of lighter shadow that may surround an umbra; for example, the spreading cone of lighter shadow cast by a space object.
Penumbra
Earth’s average distance from the Sun, which is approximately 150 million kilometers. (93 million miles)
Astronomical Unit (AU)
An oval or flattened circle.
Ellipse
Earth or a planet similar to Earth that has a rocky surface. The four planets in the inner solar system- Mercury, Venus, Earth, and Mars- are terrestrial planets.
Terrestrial planet
A large planet that consists of mostly gases in a dense form. The four large planets in the outer solar system-Jupiter, Saturn, Uranus, and Neptune-are gas giants.
Gas giant
A small, solid, rocky body that orbits around the Sun. Most asteroids orbit in a region between Mars and Jupiter called the asteroid belt.
Asteroid
A body that produces a coma of gas and dust; a small, icy body that orbits around the sun.
Comet
A brief streak of light produced by a small particle entering Earth’s atmosphere at a high speed.
Meteor
A small object from outer space that passes through Earth’s atmosphere at a high speed.
Meteorite
Relating to, measured from, or as observed from the Earth’s center.
Geocentric
Referred to or measured from the Sun’s center or appearing as if seem from it.
Heliocentric
