Inner Planets
Outer Planets
Definitions
Objects in Space
Gravity and Motion
100

Which inner planet(s) have known water

Mars and Earth

100

Which Outer planet has a red spot

Jupiter

100

Define ellipse

the casting of one celestial body's shadow on the surface of another celestial body

100

what is the asteroid belt

the imaginary line that separates the inner planets from the outer planets

100

Who discovered the laws of Gravity and motion

Isaac Newton

200

Which inner Planet(s) have the weakest gravity

Mercury and Mars

200

Where is Pluto located

In the Kuiper Belt

200

define aphelion

the point in a planet's orbit when it is farthest from the sun

200

What is the Kuiper belt

what separates Pluto from the rest of the planets

200

Which inner planet(s) have the weakest gravity

Mercury and mars

300

Which inner planet's year is the longest

Earth

300

Which outer planet has the longest day

Uranus

300

define perihelion

the point in a planet's orbit when it is closest to the sun

300

why is Pluto not considered a planet

because it is in the Kuiper belt and is too small

300

Who discovered the heliocentric world view

Nicolaus Coperincus

400

Which inner planet has the longest day

Venus

400

which outer planet has the longest year

Neptune

400

define astronomical unit

the average distance between Earth and the Sun

400

what does retrograde mean

the planet spins backwards

400

which inner planet(s) has the strongest gravity

Earth

500

What do all the inner planets have in common

They are smaller and have solid surfaces

500

What do the outer planets have in common

They have no solid surface, larger, all have rings, and beyond the asteroid belt, ect.

500

why is gravity important in the solar system

without gravity the planets would fall out of their orbit and most likely run into each other or the sun

500

which planets spin retrograde

Uranus and Venus

500

who made three laws about planetary motion

Johannes Kepler