| A | B |
|---|
| evidence | information, such as measurements or observations, that is used to explain things |
| model | something that shows or explains what the real thing is like |
| scale model | a representation of something, in which all the parts have been reduced or enlarged by the same amount |
| atmosphere | the air or gas around the planet, a moon, or a star |
| Crescent Moon | a phase when the Sun lights less than half of the side of the Moon that we see |
| cycle | a series of events that happens in the same order over and over again |
| diameter | a straight line that starts at one side of a circle, and ends at the other end of the circle |
| force | a push or pull that happens between objects |
| Full Moon | a phase when the Sun completely lights up the side of the Moon that we see |
| gibbous | a phase when the Sun lights up more than half of the side of the Moon that we see |
| gravity | an invisible pulling force between objects |
| lunar eclipse | when the Earth's shadow darkens the whole moon |
| mass | the amount of matter (stuff) in an object |
| orbit | to move around an object in space due to gravity |
| phase of the Moon | the shape the Moon seems to have when it is seen from the Earth |
| prediction | a guess that is based on evidence |
| Quarter Moon | a phase of the Moon that looks like half a full Moon |
| revolve | to move in an orbit |
| rotate | to spin |
| satellite | an object that orbits a larger object |
| scientific explanation | an explanation of something in the physical world based on all available evidence |
| scientist | a person who investigates the physical world and bases his or her explanations on evidence |
| shadow | a dark area where light is blocked by an object |
| solar eclipse | when the Moon is exactly between the Sun and the Earth |
| sphere | a ball-shaped oblect |
| system | a group of objects that form a whole and move or work together |
| three dimensional | having three dimensions (such as length, width, and height) |
| two dimensional | ving two dimensions (such as length and width) |
| weightless | not feeling the pull of gravity |
