Views of the Solar System Sun and Planets

Planet Planet means to wander. Planet means to wander. Planets change position against the background of motionless stars. Planets change position against the background of motionless stars. Planet- the largest object in the solar system that independently orbit the Sun Planet- the largest object in the solar system that independently orbit the Sun There are 8 known planets in our solar system. There are 8 known planets in our solar system.

Retrograde Motion The apparent backward motion of a planet. The apparent backward motion of a planet. Occurs because Earth is lapping the planet during its revolution. Occurs because Earth is lapping the planet during its revolution.

Inner vs. Outer Planets Inner Planet Inner Planet *small *small *close to the sun *close to the sun *solid surface *solid surface *thin atmospheres *thin atmospheres *no rings *no rings *few or no moons *few or no moons Outer Planets Outer Planets *large *large *far from the sun *far from the sun *gas surface *gas surface *thick atmosphere *thick atmosphere *have rings *have rings *many moons *many moons

Why are the Inner Planets different from the Outer Planets? The solid Inner planets formed near the Sun because the solar wind drove off lighter elements. The solid Inner planets formed near the Sun because the solar wind drove off lighter elements. The gases pushed away by the solar wind came together to form the gaseous Outer Planets. The gases pushed away by the solar wind came together to form the gaseous Outer Planets.

What separates the Inner and Outer Planets? Asteroid Belt- thousands of rocks that orbit the Sun between the orbits of Mars and Jupiter.

Mercury

Venus

Earth

Earth and Moon

Mars

Jupiter

Saturn

Saturn’s Rings

Uranus

Neptune

Pluto “the odd ball” Pluto does not fit into the Outer Planet characteristics. Pluto does not fit into the Outer Planet characteristics. *It is small and solid. *It is small and solid. *Has a moon that is over half its size. *Has a moon that is over half its size. *A unique orbit. *A unique orbit. *If Pluto was discovered today it would not be considered a planet. *If Pluto was discovered today it would not be considered a planet.

Pluto and Charon

Pluto and Its Satellite, Charon

Comets “The Dirty Snowball of Space” *They are primarily dust and ice. *They are primarily dust and ice. *They have very elongated orbits. *They have very elongated orbits. *As the comet approaches the Sun, some of the ice gets vaporized producing light. *As the comet approaches the Sun, some of the ice gets vaporized producing light. *Solar wind then pushes these gases outwards producing a glowing tail. *Solar wind then pushes these gases outwards producing a glowing tail.

Meteoroids, Meteors and Meteorites…. Oh My!!! Meteoroids- fragments of rock or ice traveling in space Meteoroids- fragments of rock or ice traveling in space Meteors- “shooting stars”, are streaks of light caused by meteoroids passing through our atmosphere Meteors- “shooting stars”, are streaks of light caused by meteoroids passing through our atmosphere Meteorites- a meteoroid that is large enough to reach Earth’s surface Meteorites- a meteoroid that is large enough to reach Earth’s surface

Impact Craters Large holes left by a meteorite, comet or asteroid collision with Earth. Large holes left by a meteorite, comet or asteroid collision with Earth. *Caused extinction of dinosaurs. *Caused extinction of dinosaurs. Why are there so few craters on Earth? Why are there so few craters on Earth? 1. Erosion 1. Erosion 2. Vegetation 2. Vegetation 3. Plate Tectonics 3. Plate Tectonics 4. Oceans and Lakes 4. Oceans and Lakes 5. Earth’s Atmosphere 5. Earth’s Atmosphere

Barringer Meteor Crater Barringer Meteor Crater, Arizona diameter: kilometers (.737 miles); age: 49,000 years Barringer Meteor Crater, Arizona diameter: kilometers (.737 miles); age: 49,000 years

Chicxulub, Yucatan Peninsula, Mexico; diameter: 170 km; age: million years

Wolfe Creek, Australia diameter: kilometers (.544 miles); age: 300,000 years

Manicouagan, Quebec, Canada diameter: ~100 kilometers (62 miles); age: 212 million years

Clearwater Lakes Canada: 290mya West Lake-20 miles diam. East Lake-13.7 miles diam.

Wolfe Creek, Australia diameter: kilometers (.544 miles); age: 300,000 years

Aorounga, Chad, Africa diameter: 17 kilometers; age: 200 mya

Bosumtwi, Ghana diameter: 10.5 kilometers ; age: 1.3 million years