Planets

The terrestrial planets and some large moons

The Jovian Planets (Gas Giants)

MercuryFacts Closest to the sun Largest range of temperature No atmosphere Moon like surface

Mercury has a cratered surface

Why are there so many craters on planets like Mercury and so few on Earth?

Venus Facts Dense cloudy atmosphere Tremendous surface pressure Hottest surface temperature (over 800 o C) Rains sulfuric acid Similar to Earth in size and surface features Runaway greenhouse effect

Earth Facts Only planet known to support life Plate Tectonics Large amounts of liquid water Substantial Oxygen atmosphere Moderate temperatures Active Plate tectonics

Mars viewed from Hubble Very thin carbon dioxide atmosphere Seasonal dust storms Polar ice caps

volcanoes Giant Canyon

Olympus Mons: largest mountain in solar system

Evidence of running water and erosion

Surface from Viking Lander

Jupiter – largest planet in the solar system fastest rotation great red spot Mostly composed of hydrogen and helium Strong magnetic field

The great red spot is a giant hurricane Colorful bands run horizontal across Jupiter’s cloud tops

Jupiter would have been a small star had it 10 to 20 times more mass Shadow of moon Io A few thousand km below the cloud tops the hydrogen turns to liquid A solid hydrogen and rock core is at the center

Composition very similar to Jupiter Saturn- the most elaborate rings It’s the lowest density of any planet and would float in water

Saturn’s rings are extremely complex and kept in line by shepherd moons

Because of it’s near 90 degree tilt, Uranus has strange seasons

Like Saturn, Uranus has a large number of moons

Neptune, like the other gas giants, is primarily hydrogen and helium Great dark spot Neptune was discovered due to gravitational discrepancies in Uranus’ orbit in 1846 by Johann Galle

Neptune as seen from it’s large icy moon Triton

Pluto and it’s moon Charon Pluto is now a “dwarf planet” It is the coldest ! only 37 degrees above absolute 0 It has the most eccentric orbit It’s orbit is most inclined to the Earth- Sun orbit plane

Other Solar System Objects would include asteroids comets

And Kuiper Belt Objects (KBO’s)- found past the orbit of Neptune As seen from Pluto Charon There are over 700,000 known, some almost as large as Pluto

Comets can be thought of as a dirty snowball that orbit the sun in very elliptical orbits They are composed of rock and ice (mostly water ice but some dry ice and other frozen gases)

typical comet orbit

Comets come from the Oort Cloud Pluto’s orbit Kuiper Belt Oort Cloud Sun The gravity from a passing star can send a comet in towards the sun

Asteroids

Most asteroids orbit between Mars and Jupiter

Meteor (shooting star) Meteors come from either a comet or asteroid

Larger meteors are called fireballs

Fireball seen over London Bridge

When a meteor (shooting star) survives it’s burn through the Earth’s atmosphere and reaches the ground it is called a meteorite

Rocky meteorite from a comet Iron meteorite from an asteroid Martian meteorite

When meteors hit earth an impact crater results Barringer Crater This impact occurred 50 thousand years ago in the Arizona desert

The Big One hit 65 million years ago

Any living thing within 2500 miles would have been vaporized in a 1 mile high wall of fire A 1000ft. high tidal wave would have swept around the world