Term |
Definition |
Sphere |
A round three-dimensional object whose surface is the same distance from its center that bulges somewhat at the equator it is slightly flattened at the poles. |
Axis |
Imaginary vertical line that cuts through the center of the earth and around which earth spins. |
Rotation |
Spinning of earth on its axis which takes about 24 hours to complete and causes day and night to occur. |
Revolution |
Earths year long elliptical orbit around the sun. |
Ellipse |
Elongated closed curve that describes earths year long orbit around the sun. |
Solstice |
Twice yearly point at which the sun reaches its greatest distance north or south of the equator. |
Equinox |
Twice yearly time each spring and fall when the sun is directly over the equator and the number of daylight and night time hours are equal world wide. |
Moon Phase |
Change in appearance of the moon as viewed from earth due to the relative positions of the moon, earth, and sun. |
New Moon |
Moon phase that occurs when the moon is between earth and the sun at which point the moon cannot be seen because its lighted half is facing the sun and its dark side faces earth. |
Waxing |
Describes phases following a new moon as more of the moons lighted side becomes visible. |
Full Moon |
Phase that occurs when all of the moons surface facing earth reflects light. |
Waning |
Describes phases that occur after a full moon as the visible lighted side of the moon grows smaller. |
Solar Eclipse |
Occurs when the moon passes directly between the sun and the earth and casts a shadow over part of the earth. |
Lunar Eclipse |
Occurs when earths shadow fall on the moon. |
Maria |
Dark colored relativity flat regions of the moon formed when ancient lava reached the surface and filled craters on the moons surface. |
Impact Basin |
A hollow left of the moon caused by an object striking its surface. |