Download Planets and Seasons

Our Solar System
A system of eight planets and many other objects
that orbit our sun
Inner Planets
The 4 solid, rocky planets closest to the sun;
Mercury, Venus, Earth, Mars
Mercury – 1st planet, moonlike appearance, 4500C during
the day, -1750C at night
Venus – 2nd planet, Earth-like,
dense CO2 atmosphere, 4640C
avg. temperature
Inner Planets (cont.)
Earth – 3rd planet, 150 million
km from the sun, or 1
astronomical unit (AU)
Mars – 4th planet, red iron-oxide
surface
Outer Planets
The 4 planets farthest from the sun; Jupiter, Saturn,
Uranus, and Neptune
Jupiter – 5th planet, largest in
solar system, gas planet
composed of liquid hydrogen,
helium & some ammonia,
methane & water vapor
Saturn – 6th planet, ringed
gas planet with the lowest
density
Outer Planets (cont.)
Uranus – 7th planet, gas planet
with rotation axis almost
parallel to its revolution
plane
Neptune – 8th planet, gas
planet similar to Uranus with
methane gas giving the blue
color
Solar System Terms
Sphere – a round, three-dimensional object
whose surface at all points is the same distance
from its center
Axis – an imaginary line around which an object
spins
Solar System Terms (cont.)
Rotation – the spinning of an object around its axis
Revolution – the orbiting of one object around another,
like Earth revolving around the sun
Ellipse – an elongated, closed curve; the shape of
planetary orbits