Solar system
The sun and it’s family of orbiting planets moons and other objects.
Galaxy
Millions or billions of stars held together in a group by there own gravity.
Universe
Space and all the matter and energy in it.
Satellite
An object that orbits a more massive object.
Impact crater
A round pit left behind on the surface of a planet or other body in space that a smaller object strikes the surface.
Axis of rotation
An imaginary line about which a turning body such as earth rotation.
Revolution
The motion of one body around another such as earth and it orbit around the sun the time it takes and object to go around once.
Season
One part of a pattern of temperature change and another weather trends over the course of a year.
Equinox
In an orbit a position and time in which sunshines equally on the northern hemisphere and the Southern Hemisphere a time of year when day light and darkness are nearly equally on earth.
Solstice
In an orbit a position and time during which one hemisphere gets it’s maximum area of day light wile the other hemisphere gets it’s maximum amount.
Mare
A mare is an adult female horse.
Eclipse
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer.
Umbra
The umbra, penumbra and antumbra are three distinct parts of a shadow, created by any light source after impinging on an opaque object. For a point source only the umbra is cast.
Penumbra
the partial or imperfect shadow outside the complete shadow of an opaque body, as a planet, where the light from the source of illumination is only partly cut off.
Astronomical unit
The astronomical unit is a unit of length, roughly the distance from Earth to the Sun. However, that distance varies as Earth orbits the Sun, from a maximum to a minimum and back again once a year.
Ellipse
In mathematics, an ellipse is a curve on a plane that surrounds two focal points such that the sum of the distances to the two focal points is constant for every point on the curve.
Terrestrial planet
Within the Solar System, the terrestrial planets are the inner planets closest to the Sun. Mercury, Venus, Earth, and Mars. The terms “terrestrial planet” and telluric planets are derived from Latin words for Earth.
Gas giant
A gas giant is a giant planet composed mainly of hydrogen and helium. Jupiter and Saturn are the Solar System’s gas giants.
Comet meteor
A small particle from an asteroid or comet orbiting the Sun. Meteor: A meteoroid that is observed as it burns up in the Earth’s atmosphere - a shooting star. Meteorite: A meteoroid that survives its passage through the Earth’s atmosphere and impacts the Earth’s surface.
Meteorite
A meteorite is a fragment of rock or iron from outer space, usually a meteoroid or asteroid, which survives passage through the atmosphere as a meteor to impact the surface of the Earth. Meteorites are believed to originate in the asteroid belt between the planets of Mars and Jupiter.
Geocentric
In astronomy, the geocentric model (also known as geocentrism, or the Ptolemaic system) is a description of the cosmos where Earth is at the orbital center of all celestial bodies.
Heliocentric
having or representing the sun as the center, as in the accepted astronomical model of the solar system.
Gravity
Gravity or gravitation is a natural phenomenon that brings towards one another like stars planets and even light by sub atomic particles.
Tide
Tides are the rise and fall of sea levels caused by the combined effects of gravitational forces exerted by the Moon, Sun, and rotation of the Earth.
