| A | B |
|---|
| maria | smooth lowland plains on the moon |
| perigee | closest point of an object in orbit |
| apogee | farthest point of an object in orbit |
| solar eclipse | when the moon blocks the sun from the Earth |
| umbra | inner part of a shadow |
| penumbra | outer part of a shadow |
| lunar eclipse | when the Earth blocks the sun from the moon |
| tide | rise and fall of oceans caused by the Moon's gravity |
| spring tide | higher tide during full or new moon phase |
| neap tide | lower tide during the first or last quarter moon phase |
