Inner and outer planets

Because Mercury's mass is so small, it

Has no atmosphere

why is Venus the hottest inner planet?

It's atmosphere traps a lot of heat energy

How is Venus unlike other planets?

Its period of rotation is longer than its period of revolution.

Which planet is the largest in the solar system?

Jupiter

Which inner planet has the longest period of revolution and why?

Mars

Why do scientists think that liquid water might have existed on Mars?

Mars's surface has deep gullies in it

Which planet has a moon larger than Mercury?

Saturn

All inner planets

are rocky and have a solid outer layer

All the outer planets are made mostly of

gas and liquid around a solid core

Jupiter

has 63 moons

Saturn

has the most complex ring system

The outer planets have atmospheres composed mostly of

hydrogen and helium

Earth is the only planet with a wide variety of life because of its

moderate temperature and liquid water

Neptune

size, makeup and structure are like that of Uranus

Uranus

spins on its side