1. Touring Our Solar System
Chapter 23
Touring Our Solar System

2. The Solar System
The sun is the center of a huge rotating system of nine planets, their satellites, and numerous smaller bodies
99.85% of the mass of the solar system in contained with the sun
Together the planes make up most of the reaming .15%
The sun’s gravity guides the planets in their orbits

3. Two Groups of Planets Terrestrial (Earth Like) Jovian (Jupiter Like)
Mercury, Venus, Earth, Mars
Small
Rocky (metallic minerals)
Closer to the Sun (inner planets)
Dense
Thin Atmosphere
Few Moons
No Rings
Jupiter, Saturn, Uranus, Neptune
Huge (called Giants)
Gas (Hydrogen & Helium)
Farther from the Sun (outer planets)
Not Dense
Thick atmosphere
Many Moons
Rings

4. Inner Planets
Outter Planets

5. Formation of the Solar System
Nebular Theory (Nebula – a rotating cloud of dust and gas)
The sun an planets formed from a rotating disk of dust and gases.
As speed of rotation increased the center of the disk began to flatten out
Matter became more concentrated in the center, where the sun eventually formed.
Planets began to form as matter started to collide and clump together
Baby planets called planetesimals began to form

6. Nebular Theory
Solar System formed from a rotating cloud of dust and gas

7. The Terrestrial Planets
Mercury, Venus, Earth, Mars

8. Mercury: The Innermost Planet
Smallest planet (a little bigger than our moon)
Highlands, and smooth areas like Maria on the moon
Very dense due to large iron core
Revolves quickly (88 Earth days)
Rotates slowly (takes 59 Earth days)
Has the greatest temperature extreme of any planet
Night -173˚C
Day 427˚C

9. Mercury
If you weigh 100 pounds on Earth, you would only weigh 37 pounds on Mercury.
Because of the lack of atmosphere, Mercury's sky is black and the stars probably can be seen during the day.

10. Venus: The Veiled Planet
Second only to the moon in brightness in the night sky
Rotates around sun once every 225 Earth days
Similar to Earth in sixe denisty and mass
Covered in clouds that visible light cannot penetrate
Volcanism and tectonic activity shape Venus
Surface Temperature around 475˚C (due to greenhouse effect)
Atmosphere is 97% carbon dioxide

11. Venus
Named after the goddess of love and beauty
Called Earth’s twin

12. Mars: The Red Planet
Appears as a reddish ball when viewed through a telescope
Has white polar caps (made of water ice and covered in frozen Carbon Dioxide)
Atmosphere is mainly Carbon Dioxide
Has extensive dust storms with hurricane force winds
Probes have shown terrain similar to a rocky desert on Earth
Large volcanoes
Olympus Mons – size of Ohio and 23 km high (2 ½ times taller than Mt. Everest)
Large Canyons (bigger than Grand Canyon)

13. Mars Named after the Roman god of war an agriculture
The month of March is named after Mars
Red Color due to Iron Oxide (rust)

14. Mars Rover
Launched to Mars to gather information

15. Jupiter, Saturn, Uranus, Neptune
The Outer Planets
Jupiter, Saturn, Uranus, Neptune

16. Jupiter: Giant Among Planets
Largest Planet (still only 1/800th of the sun)
If it was 10 times larger it would have been a star
Rotates faster than any other planet (10 Earth hours)
Great Red Spot which is giant storm
Atmosphere is Hydrogen, Helium, small amount of methane, ammonia, water and sulfur
Winds create the banded look
Has 28 moons
Has a very faint ring system

17. Jupiter
Jupiter has been visited by 8 spacecraft.  These were Pioneer 10, Pioneer 11, Voyager 1 and 2, Galileo, Ulysses, Cassini and New Horizons.  The very first mission to explore Jupiter was Pioneer 10, an American spacecraft launched in 1972.  This was a true pioneering mission in that, before it left Earth, no one knew whether spacecraft could travel through the asteroid belt between here and Jupiter and survive the trip.  

18. Saturn: The Elegant Planet
One revolution takes 29.6 Earth Years
Very similar to Jupiter
Has a prominent ring system
Made of small pieces or rock and ice that orbit the planet
Very thin 100 meters from top to bottom
Strong winds up to 1,500 km/hr
At least 31 moons

19. Saturn Cannot stand on Saturn it is all gas (hydrogen and helium)
Could float on water since it is mostly gas

20. Uranus: The Sideways Planet
Rotates on its side
Looks like it is rolling
Has a ring system

21. Uranus Coldest planet in the solar system
You can see it with the unaided eye

22. Neptune: The Windy Planet
Winds that exceed 1,000 km/hr
Has an Earth size blemish called the Great Dark Spot
It is a giant storm

23. Neptune
The only spacecraft that has ever visited Neptune was NASA’s Voyager 2 spacecraft

24. Minor Members of the Solar System

25. Asteroids
Small rocky bodies (most about 1km across, largest 1,000km, smallest grain of sand)
Most lie between Mars and Jupiter
Thought to be remains of a planet that once was located between Mars and Jupiter

26. Comets
Pieces of rocky and metallic materials held together by frozen gasses
Most interesting and unpredictable bodies in the solar system
Travel in very long elongated orbits that take hundreds of thousands of years to complete a single orbit around the sun
Some comets have orbital periods of less than 200 years (short period comets)

27. Parts of a Comet
Coma – the glowing head of a comet created by the sun vaporizing frozen gases
Nucleus – Rocky bodies that are surrounded by the Coma (40m to 100 km across)
Tail – always points away from the sun (due to Solar Wind)

28. Halley’s Comet
Most famous short period comet orbital period is 76 years
Next appearance 2061

29. Kuiper Belt and Oort Cloud
Two locations where most comets come from
Short orbital periods come from Kuiper Belt
Long orbital periods come from Oort Cloud

30. Meteoroids, Meteors, Meteorites
Meteoroid – small solid particle that travels through space
Meteor – the light produced as a meteoroid enters the atmosphere (shooting star) * doen’t last for a long time it is short meteor is the shortest word
Meteorite – When a meteoroid hits Earth’s surface *Ends with an E and it ends on Earth’s surface
Meteorite
Meteor