Space Vocabulary Flashcards
Orbit
The circular elliptical path of an object as it revolves around another object.
Solar system
A system of objects that revolve around a star.
Galaxy
a group of solar systems, dust, and gas held together by gravity; our solar system is part of the Milky Way galaxy
universe
everything that exists in, on and around the Earth
Satellite
a natural or artificial object that revolves around another object in space
Impact Crater
a large, circular pit in the surface of a planet or other body in space usually formed when two bodies in space collide
Rotation
the spinning of a celestial body, such as a planet, around an axis
Revolution
the orbiting of an object around another object
Season
a period of the year determined by the position of Earth as it revolves around the sun
Equinox
the twice-a-year occurrence during which Earth’s axis is perpendicular (at a 90 angle) to a line joining the Sun and Earth’s center
Solstice
the twice-a-year occurrence during which the Sun appears at the highest point in the sky as seen from the North or South pole
Mare
are large, dark, basaltic plains on Earth’s Moon
Eclipse
an event whereby one astronomical body passes between two other astronomical bodies
Umbra
the fully shaded inner region of a shadow cast by an opaque object
Penumbra
the partially shaded outer region of the shadow cast by an opaque object.
Astronomical Unit
the mean distance from the center of the Earth to the center of the sun (about 149.6 million kilometers); used to measure distances in the solar system
Ellipse
a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points
Terrestrial Planet
telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals
Gas Giant
a state of matter without any defined volume or shape (related word: gaseous)
Asteroid
a small object made of rock or metal that orbits the sun
Comet
a body of ice and dust that travels in a long narrow orbit around the sun
Meteor
a streak of light in the sky that forms when a piece of rock from space burns up in Earth’s atmosphere (related term: shooting star)
Meteorite
a piece of rock or metal from space that strikes Earth’s surface
Geocentric
having the Earth as the center
Heliocentric
having the sun as the center
Gravity
a force that exists between any two objects that have mass (related word: gravitational)
Tide
the regular fluctuation of sea water driven by the gravitational pull of the Moon and Sun on Earth’s oceans and other large bodies of water
Waxing
the moon at any time after new moon and before full moon
Wannig
(of the moon) have a progressively smaller part of its visible surface illuminated
Gibbous Moon
gibbous refers to a moon in between a half-moon but less than a full moon
Crescent Moon
The Moon as it appears early in its first quarter or late in its last quarter
Full Moon
the lunar phase when the Moon appears fully illuminated from Earth’s perspective
New Moon
the phase of the moon when it is in conjunction with the sun and invisible from earth
Quarter Moon
when we see the Moon half illuminated by the Sun
Perihelion
the point in the orbit of a solar system body when it is closest to the Sun
Aphelion
the point in the orbit of a planet or other orbiting body where it is farthest from the Sun or the body around which it revolves
