Earth Compared to Other Planets and Moons

Earth Earth: the third planet from the sun Atmosphere: 78% Nitrogen 21% Oxygen 1% other gases Ozone layer to protects it from harmful UV radiation Greenhouse gases hold in heat and protect Earth from meteor impacts

Earth Lithosphere: liquid iron in the outer core creates a protective magnetic field Hydrosphere Liquid water is abundant Temperature -126 °F to 126 °F

The Moon The Moon: Earth’s only satellite Atmosphere Lithosphere Very Thin; hydrogen and helium No protection from meteors Lithosphere No liquid metal = No magnetic field Hydrosphere No water Temperature -280 °F to 260 °F

Mercury Mercury: closest planet to the sun Atmosphere: Lithosphere Very thin; Hydrogen and helium No protection from meteors Lithosphere Little magnetic field (1% of Earth’s) Hydrosphere No water Temperature -290 °F to 800 °F

Venus 2nd planet from the sun Atmosphere Lithosphere Hydrosphere 93 times thicker than Earth’s 96% Carbon Dioxide Lithosphere Little magnetic field (1% of Earth’s) Volcanoes and mountains Hydrosphere Traces of water vapor Temperature 870 °F

Mars 4th planet from the sun Atmosphere Lithosphere Hydrosphere 100x thinner than earth’s 96% Carbon Dioxide 0.1% Oxygen Lithosphere Past volcanoes Solid core: no magnetic field Hydrosphere Evidence of seasonal water Temperature -195 °F to 70 °F

Jupiter 5th planet from the sun Atmosphere Lithosphere Hydrosphere 10x thicker than earth’s 90% Hydrogen, 10% Helium Lithosphere Magnetic field 14x stronger than earth’s Hydrosphere Water vapor in the atmosphere Temperature -230 to 70 °F

Io The closest of Jupiter’s moons Atmosphere Lithosphere Hydrosphere Made up of mostly Sulfur dioxide SO₂ Lithosphere Covered in volcanoes Liquid core = magnetic field Hydrosphere No water Temperature -290 to 2240 °F

Europa The 16th closest moon to Jupiter Atmosphere Lithosphere Very thin and made up of mostly Oxygen Gas Lithosphere Small magnetic field Surface is covered in water ice Hydrosphere Ocean under the ice?? Temperature -275 °F Water

Ganymede Atmosphere Lithosphere Hydrosphere Temperature Very thin and mostly oxygen gas Lithosphere Magnetic field Surface is rocky with frozen water ice Hydrosphere Frozen water on the surface Temperature -290 to -170 °F

Saturn The 6th planet from the sun Atmosphere Lithosphere Hydrosphere Thick with 75% hydrogen and 25% helium Lithosphere Magnetic field slightly weaker than Earth’s Hydrosphere No water Temperature -270 ⁰F

Enceladus Atmosphere Lithosphere Hydrosphere Temperature Thin and mostly water vapor Lithosphere Magnetic field Frozen water on surface with geysers Hydrosphere Liquid and frozen water Temperature -400°F to -200 °F

Titan Atmosphere Lithosphere Hydrosphere Temperature 1.5x earth’s atmosphere in thickness 98% nitrogen 2% methane Lithosphere Magnetic field Liquid nitrogen and methane on the surface Hydrosphere No water Temperature -290 °F

Uranus 7th planet from the Sun Atmosphere Lithosphere Temperature 10x thicker than earth’s Hydrogen, Helium and Methane Lithosphere Magnetic field Small rocky core with a liquid surface Temperature -35 °F Hydrosphere No water

Neptune 8th planet from the sun Atmosphere Lithosphere Temperature Hydrogen, Helium and Methane Lithosphere Magnetic field Small rocky core with a liquid surface Temperature -390 °F Hydrosphere No water

Dwarf Planet Dwarf Planet: an object that orbits the sun, is not a satellite and has not cleared the space around its orbit

Pluto A dwarf planet in the Kuiper belt Atmosphere Lithosphere Thin with Methane and nitrogen gases Lithosphere Rocky with frozen methane and nitrogen on the surface Temperature -375 °F Hydrosphere No water

Comparative Planetary Data Au Km “1 year” (once around the sun) “1 day” (spins on its axis) Earth masses Density Satellites (moons) Mercury 0.39 58 88 days 59 days 0.06 5.4 Venus 0.72 108 225 days 244 days 0.82 5.2 Earth 1 150 365 days 24 hours 5.5 Mars 1.52 228 687 days 0.11 3.9 2 Jupiter 5.20 778 12 years 10 hours 317.87 1.3 63 Saturn 9.54 1427 29.5 years 95.14 0.7 62 Uranus 19.18 2870 84 years 17 hours 14.56 1.2 27 Neptune 30.06 4497 165 years 16 hours 17.21 1.7 13 Pluto 39.44 5900 248 years 6.4 days 1.8

Which planet or moon would be most habitable? Choose one of the moons or planets we just talked about. In your packet, write a paragraph (4-6 sentences) explaining why you picked that planet or moon and what life forms would need to survive there.