~Solar System~ Kelly Huson EDU-370

Inner Solar System Terrestrial or Rocky Planets

Outer Solar System Gas Planets

‘Origin’ of the Solar System Gas/Dust cloud collapses and compresses in center Forming star with orbiting gas that forms an accretion disk First Break Point Gas cools off and particles form Run away growth Second Break Point “Planetesimals” Current Solar System

Sizes

Sun

Mercury Mercury is the closest planet to the Sun and the eighth largest. Its orbit is highly eccentric It is the only body in the solar system known to have an orbital/rotational resonance with a ratio other than 1:1 Temperature variations are the most extreme in the solar system ranging from 90 K to 700 K. Mercury is the second densest major body after Earth It has a very thin atmosphere consisting of atoms blasted off its surface by the solar wind.

Venus Venus' rotation is very slow and retrograde Earth’s sister planet, their densities and chemical compositions are similar Venus is only slightly smaller than Earth, 95% of Earth's diameter & 80% of Earth's mass It is composed mostly of carbon dioxide with thick layers of clouds composed of sulfuric acid. This dense atmosphere produces the Greenhouse Effect Actually hotter than Mercury High Volcanic Activity

Earth

Mars Called the Red planet Orbit very elliptical Seventh Largest Same surface area as Earth, but overall much smaller Varied terrain-between north & south hemispheres No lateral plate motion Very thin atmosphere Early in its history it was much like Earth

Jupiter 5th Planet, Largest Gas planet: 90% H % 10% He 3 distinct layers of clouds High velocity winds Radiates more energy than receives from the sun Huge Magnetic Field Has rings-continually resupplied 63 know satellites

Saturn 6th Planet, 2nd Largest Planet Least dense of the planets Gas planet - 75%H and 25%He Radiates more energy than receives from sun Thin rings composed of small particles & ice Significant magnetic field 34 named satellites

Uranus 7th Planet , 3rd Largest First planet discovered in modern times Axis almost parallel to the ecliptic Poles are in unusual location Composed of rock and various ices Bands of rapidly moving faint clouds Blue in color Has 11 rings Has 27 moons

Neptune 8th sometimes 9th Planet due to eccentric orbit Similar composition to Uranus Gas planet with rapid winds fastest in solar system Has 4 rings Oddly oriented magnetic field Has 26 known moons

Pluto Usually furthest from Sun Smallest Planet, smaller than some moons Only planet not visited Discovered on accident Has satellite - Charon Highly eccentric orbit with 3:2 resonance with Neptune Equator almost at right angle with orbit (like Uranus) Little known about atmosphere