| A | B |
|---|
| apogee | the point farthest from Earth in the orbit of an Earth satellite |
| solar noon | when the sun is at the highest position in the sky |
| altitude | height of an object in the sky above the horizon |
| aphelion | the point in a planet's orbit which is farthest from the sun |
| geocentric model | has the Earth as its center |
| heliocentric model | has the sun as its center |
| rotation | turning of an object on its axis |
| revolution | movement of Earth around the sun |
| orbit | the path of a revolving body |
| astronomical unit | average distance from the Earth to the sun |
| period | the subdivision of an era |
| perigee | point nearest Earth in orbit of Earth satellite |
| solar eclipse | moon's shadow falls on Earth |
| spring tide | occurs at new-moon and full-moon phases |
| neap tide | occurs at the quarter phase of the moon |
| phases | daily change in the moon's appearance |
| lunar eclipse | moon passes into Earth's shadow |
| galaxy | a group of millions of stars held together by gravity |
| perihelion | place in planet's orbit when nearest the sun |
| Coriois Effect | deflects moving objects toward or away from the Earth's equator |
