The Outer Planets of Our Solar System Jupiter, Saturn, Uranus, Neptune

Outer Planets The outer planets are also called “gas giants” These planets are much larger than the others in the solar system These planets are less dense than the others in the solar system

Jupiter 5th planet from the sun Largest planet in the solar system Planet with the shortest day Possibility of liquid water on Jupiter’s moon, Europa Has 79 natural satellites as of July 2018 Thin ring system made of dust

Jupiter’s Great Red Spot

Jupiter- Fast Facts Surface temperature range: −145°C to -20°C 55, 206 miles in diameter Rotates in 9.8 Earth hours Rotates counterclockwise Revolves in 11.86 Earth years The 4 Galilean moons are Io, Europa, Ganymede, and Callisto 5.2 AU (average distance from the sun) Atmosphere: mostly hydrogen

Jupiter

Jupiter as seen from Voyager 1

Saturn 6th planet from the sun Second largest planet in the solar system Has the most easily visible ring system in the solar system The rings are made of ice and other matter The rings are not solid, but appear connected from far away One of Saturn’s moons (Rhea) has its own ring system

Saturn’s “Rings” and Rhea

Saturn- Fast Facts Surface temperature range: −175°C to about -130°C 46,354 miles in diameter Rotates in 10 Earth hours Rotates counterclockwise Revolves in 29.46 Earth years 62 confirmed moons (Largest is Titan, 2nd largest is Rhea) 9.55 AU (average distance from the sun) Atmosphere: mostly hydrogen

Saturn

Uranus 7th planet from the sun Has a ring system Extreme seasonal variation in weather Rotates clockwise (retrograde) and on its side Has a strong magnetic field Contains a lot of ice

Uranus

Uranus- Fast Facts Surface temperature range: −214°C to about -200°C 19,616 miles in diameter Rotates in 17 Earth hours Rotates clockwise Revolves in 84 Earth years 15 moons 19.2 AU (average distance from the sun) Atmosphere: mostly hydrogen

Uranus on its side

Neptune 8th planet from the sun Last true planet in our solar system Contains a lot of ice Has rings Neptune’s Great Dark Spot is a continuous giant storm

Neptune’s Great Dark Spot

Neptune- Fast Facts Surface temperature range: −223°C to about -220°C 18,765 miles in diameter Rotates in 16 hours and 17 minutes (Earth) Rotates counterclockwise Revolves in 165 Earth years 13 known moons 30.1 AU (average distance from the sun) Atmosphere: hydrogen, helium and methane Methane makes Neptune look blue

Neptune

Dwarf Planets The area beyond Neptune is called the Kuiper belt This is where most dwarf planets are found Pluto and Eris are dwarf planets Dwarf planets orbit the Sun, have their own gravity but have not cleared its surrounding region of planetesimals Planetesimals are solid objects (including dust) that form celestial bodies