Earth Science

Mrs. Harris

This week’s objectives

• Characteristics of the inner planets

• Characteristics of the outer planets

• Comparing the size and distance

Inner Planets

• Also called Terrestrial Planets

• Composed mostly of rock

• Closest to the sun– Mercury, Venus, Earth, & Mars

Mercury

• Takes 88 Earth days to travel around the sun

• Takes 59 days to rotate once on its axis

• Being so close to the sun, it gets really hot! But without much of an atmosphere the heat leaves quickly! – Today on Mercury we’ll have a balmy high of 800oF and a

night time low of chilly -280oF

Venus

• Takes 225 days to orbit the sun• Takes 243 days to rotate on its axis!!!

• Most similar to Earth (size, density, distance from sun)… however…

• Atmosphere of 97% carbon dioxide- it’s greenhouse effect is extreme!– If you like sunny days and temperatures around

860oF, then Venus is for you!

Earth

• Takes 365 ¼ days to orbit the sun• Rotates on its axis once a day

• One moon named Moon • Amazing combination of liquid water and an

oxygen-rich atmosphere to support life • Temperatures range from -160oF to 140oF

Mars

• Takes 687 days to orbit the sun

• Takes about 24 hours to rotate on it’s axis

• Because of a tilt in the axis, Mars also experiences seasonal changes

• Two moons: Phobos and Deimos

• Temperatures from -125oF to 23oF

Martians?

• Scientists have been looking for evidence of life on Mars

• Scientists have also been looking for water on Mars

• Some think it is possible for us to make an atmosphere on Mars to eventually make it a second planet for us! We could be the first Martians!

• http://videos.howstuffworks.com/tlc/31625-solar-empire-turning-mars-into-earth-video.htm

Outer Planets

• Also called the Gas Giants

• An asteroid belt separates the inner and outer planets

• All the Gas Giants are less dense than the inner planets and they all have rings– Jupiter, Saturn, Uranus, & Neptune

– (Remember Pluto was taken off the list of official planets and is now a dwarf planet)

Jupiter• Takes 12 years to orbit the sun• Fastest rotation: about 10 hours on its

axis– Jupiter’s mass = mass of all other planets x

2!– Made of mostly helium and hydrogen

• Has about 60 moons! Four are the size of small planets: Io, Europa, Callisto, & Gannymede

• The Great Red Spot (3 Earth’s would fit in it)

• Average temperature: a brisk -230oF

Saturn

• Takes 29 ½ years to orbit the sun

• Takes about 10 ½ hours to spin on it’s axis

• Most famous for it’s rings- made of ice and dust debris

• Saturn has 47 moons… so far

• Saturn also consists mostly of helium and hydrogen, but is the least dense of all

• You’ll find a chilly average temp of -280oF

Uranus

• Takes 84 years to get around the sun• Rotates on it’s axis every 17 hours• Unlike other planets, it’s axis mostly points

towards the sun• Has 27 moons and 11 rings• Also, mostly made of helium and hydrogen

but it’s blue appearance comes from methane in the atmosphere

• Cool blue -360oF

Neptune

• Takes about 164 years to orbit the sun• Rotates on it’s axis about every 16 hours• Is also blue because of methane• It was known before it was seen! Because it

affects the orbit of Uranus, astronomers were able to figure out where Neptune was located before it was seen!

• 13 moons and 6 rings and a nippy -350oF

Pop Quiz

• What is the name of the region beyond the Gas Giants?

*hint… it’s a belt*

Comparisons

• Check out this video that gives a great visual on the sizes of the planets and even the size of our sun against other stars!

• http://www.youtube.com/watch?v=BS88G5WBcfQ&feature=PlayList&p=3C4F39B2897AEFE6&playnext=1&playnext_from=PL&index=20

• We’re going to group up and fill out the table on the next slide:

• http://science.nationalgeographic.com/science/space/solar-system.html

Planet Diameter Distance from sun

130 lbs. weighs…

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

“Pluto”