Long, long ago in a galaxy

far, far away (room 5-1),

a group of fifth graders (that’s you!)

were learning about space…

Space The Final Frontier

Part 1 – Planets in Our

Solar System

What is a solar system?

• A system of planets, moons, comets, asteroids, dust, gases, and anything else that orbit a star and are tied to its gravitational force

• The sun (a yellow star) is the center of our solar system

Previously in the study of space…

• Around 200 BC– Aristarchus (Greek)– Sun was the center

• Ptolemy– Greece, early 100s– The earth was the

center of the universe

• Copernicus– Polish astronomer– 1543– The sun was the

center of the

solar system– Planets revolved

in circles around

the sun– Proved using mathematical data

• Modern Model– Early 1600s– Johannes Kepler– Planets travel in elliptical (oval-shaped, like a

flattened circle) orbits around the sun– Proven mathematically by Sir Isaac Newton

Modern Model of the Solar System

Planets

• AKA major planets• A body that revolves around the sun• Gravity keeps them in orbit• Shine because they reflect light from the

sun• Mercury, Venus, Earth, Mars, Jupiter,

Saturn, Uranus, Neptune– Many Very Entertaining Monkeys Just Stay

Up Nights

Planets continued

• Revolve around the sun (year)

• Rotate (spin) on an axis (day/night)

The Inner PlanetsMercury, Venus,

Earth, Mars

Mercury

• Closet planet to the sun• Diameter (distance across): 3,000 miles• Temperature: Between 800 degrees and

-280 degrees Fahrenheit (F)• Distance from the sun: 36 million miles• Length of day (in Earth time): 176 days• Length of year (in Earth days): 88 days• Natural satellites: 0

Mercury

Special characteristics:– Smallest planet– Moon-like surface– Dry, hot, airless

(no atmosphere)– Oldest surface– Least explored– Sun’s rays are 7 times as strong as they are on Earth– Travels at a speed of 104,000 mph– Named for the Roman god of trade and profit

Venus

• 2nd planet

• Diameter: 7,520 miles

• Temperature: 864 degrees F

• Distance from the sun: 67 million miles

• Length of day: 243 days

• Length of year: 225 days

• Natural satellites: 0

Venus continued

• Special characteristics:– Brightest object in morning and evening sky (outside

of moon)– Clouds of sulfuric acid, hurricane force winds, and

lightning– Heavy atmosphere – carbon dioxide, nitrogen– One school day on Venus would last 4 months!– Almost all features are named for extraordinary Earth

women– Named for Roman goddess of love– Spins backwards

Earth

• 3rd planet

• Diameter: 7,926 miles

• Average temperature: 59 degrees F

• Distance from the sun: 93 million miles

• Length of day: 24 hours

• Length of year: 365 days

• Natural satellites: 1

Earth continued

• Special characteristics:– 2/3 water, 1/3 land– Only planet known to have living things– Nitrogen and oxygen

• Oxygen rich environment

– Travels at a speed of 64,000 mph

Mars

• 4th planet

• Diameter: 4,200 miles• Average temperature: -81 degrees F• Distance from the sun: 142 million miles• Length of day: 24.62 hours• Length of year: 687 days (1.88 years)• Natural satellites: 2

Mars continued

• Special characteristics:– “Red Planet” – red soil contains rust– Dark blue-gray/greenish “seas”– No water on surface, frozen water beneath surface– Thin air, mostly carbon dioxide– 1997 – Mars Pathfinder landed on Mars– Present Day: Spirit and Opportunity rovers– It would take 5 minutes to travel to Mars at the speed

of light– Named for Roman god of war

Mars

North is at the center, south is at both ends

The Outer PlanetsJupiter, Saturn,

Uranus, Neptune

Jupiter

• 5th planet• Diameter: 88,915 miles• Average temperature: -

234 degrees F• Distance from the sun:

484 million miles• Length of day: 9 hours• Length of year: 12 years• Natural satellites: 62

Jupiter continued

• Special characteristics:– Largest planet– Giant ball of gas– Heavy pressure turns gas into liquid– Giant red spot – giant storm that has lasted hundreds

of years– Stripes and swirls are cloudy, windy clouds of

ammonia and water– Poisonous atmosphere – hydrogen and helium– 49 moons, 3 rings (“mini solar system”)– Named for the king of ancient Roman gods

Saturn

• 6th planet• Diameter: 75,000 miles• Average temperature: -288 degrees F• Distance from the sun: 886 million miles• Length of day: 11 hours• Length of year: 30 years• Natural satellites: at least 53

Saturn continued

• Special characteristics:– First viewed through a telescope by Galileo in 1610– Made of hydrogen, helium and methane– No solid surface– Pressure makes gas into liquid– Yellow and white clouds– “Jewel” of our solar system – 6 major rings– Speed of wind at equator: 1,100 mph– Named for the Roman god of agriculture

Uranus(YOOR un nus)• 7th planet• Diameter: 31,760 miles• Average temperature: -357 degrees F

(core temperature 9,000 degrees F)• Distance from the sun: 1.7 billion miles• Length of day: 17 hours• Length of year: 84 years• Natural satellites: 27

Uranus continued

• Special characteristics:– Tilted sideways– 11 rings– No solid surface – Blue-green color due to methane gas– Atmosphere: hydrogen, helium, methane, water,

ammonia– Named for Roman god – father of the Titans– Tremendous pressure– Seasons last 20 years

Neptune

• 8th planet

• Diameter: 30,700 miles

• Average temperature: -353 degrees F

• Distance from the sun: 2.8 billion miles

• Length of day: 16 hours

• Length of year: 165 years (2011)

• Natural satellites: 13

Neptune continued

• Special characteristics:– Blue color from methane gas– Located through math, rather than

observation– Incredible pressure – May have a super hot ocean– Winds: 1,200 mph– Named for the Roman god of the sea– Invisible to naked eye– 6 rings

Dwarf Planet

• Orbits the sun

• Has sufficient mass to be nearly round

• Is not a satellite

• Does not clear the neighborhood around its orbit

• Could be called “plutoid” if located beyond Neptune

Dwarf Planets

• Pluto– Previously known as the ninth planet– Average temperature: -356 degrees F– Distance from the sun: 4.6 billion miles– Length of day: 6.4 Earth days– Length of year: 248 years– Natural satellites: 3– Orbit crosses Neptune’s orbit

• UB313 or Eris – 10 billion miles from the sun– Takes twice as long as Pluto to orbit the sun

Dwarf Planets

• Ceres– Located in the asteroid belt between Mars and Jupiter

• MakeMake (new official name for Dwarf Planet 136472 2005 FY9) – Located beyond Neptune

• Haumea (new official name for Dwarf Planet 136108 2003 EL61, originally called "Santa.“)– Located in the Kuiper Belt

Credits

• Scott Foresman Science

• www.nasa.gov

• Scholastic News

• Google Images

• Dictionary.com