| A | B |
|---|
| The planet that is like a sun | Jupiter |
| The planet which is both one of the hottest and one of the coldest | Mercury |
| The smallest planet | Pluto |
| THe planet which is covered with thick acid clouds | Venus |
| The hottest planet | Venus |
| The red (rusty) planet | Mars |
| The planet with the largest volcano | Mars |
| 4 planets with rings | Jupiter, Saturn, Uranus, Neptune |
| The double planet | Pluto |
| 4 biggest planets | Jupiter, Saturn, Uranus, Neptune |
| Most recently discovered planet | Pluto |
| The planet with the unusual orbit | Pluto |
| Planets with zero moons | Mercury and Venus |
| A planet's year | Period of revolution |
| A planet's day | Period of rotation |
| The time it takes a planet to make one trip around the sun | Period of revolution |
| Forces that keep planets in orbit | Inertia and Gravity |
| Planets made of rock and metal | Inner planets |
| Gas planets | Outer planets |
| Theory that describes the beginnings of the solar system | Nebular Theory |
| How much the planet's orbit deviates from circular | Eccentricity of orbit |
| Described how planets stay in orbit | Newton |
| Discovered that planets have elliptical (not circular) orbits | Kepler |
| Discovered that the sun is the center of the solar system | Copernicus |
| How close a planet is to the orbit of the earth | Inclination of Axis |
| The planet with the most rings | Saturn |
| The ice moon of Jupiter | Europa |
| Largest planet | Jupiter |
| Possible body on the outside of the universe | Planet X |
| The planet which would float on water | Saturn |
| The planet which has longer days than years | Venus |
| Pluto's moon/sister planet | Charon |
