| A | B |
|---|
| spinning motion of a planet on its axis | rotation |
| movement of an object around another object | revolution |
| wobbling motion on a planets axis | precession |
| study of objects in space | astronomy |
| two days a year where day equals night | equinox |
| the longest and shortest day of the year | solstice |
| tendency of an object to resist change | inertia |
| the attractive force between objects | gravity |
| amount of matter in an object | mass |
| force of gravity on an object | weight |
| path of an object around another object in space | orbit |
| the shape of a planets orbit | ellipse |
