Inner and Outer Planets

Inner Planets

• Terrestrial planets are those that are closest to the Sun.

• Terrestrial planets are made mostly of rock and have similar characteristics to Earth.

• There are four terrestrial planets in our solar system.• Mercury• Venus• Earth• Mars

•Inner Planets

Mercury• Closest to the sun

• No moons

• Extremely hot temperatures on one side and extremely cold temperatures on the other.

• Now the smallest planet in our solar system

• Physically, Mercury is similar in appearance to our moon as it is heavily cratered.

• Mercury has a rocky body like the Earth, but its atmosphere is very thin or weak.

• Brain Pop Mercury

Venus: “Earth’s Twin”

• Second planet from the sun

• Rotates in the opposite direction than earth

• Venus has no moons

• Is the hottest planet

• Has the most dense atmosphere than any of the terrestrial planets

• Mainly consists of carbon dioxidebut also some deadly acids

• The carbon dioxide traps thermal energy causing a greenhouse effect-causing the temperature to be so high

• Average temperature 464*C

Venus• Venus is the brightest object in the

sky after the Sun and the Moon, and sometimes looks like a bright star in the morning or evening sky. We can't see the surface of the planet because it has a very thick atmosphere filled with clouds that strongly reflect sunlight.

• Brain Pop Venus

Earth• Earth is the “water planet,” which is the reason

for the survival of life on this planet.• Temperatures on Earth are warm enough to

keep the water from freezing but cool enough to keep it from boiling away.

• Earth has three layers:1. The crust is the outer layer of the Earth.2. The mantle lies below the crust. It contains

denser rocks.3. The core, at the center, contains the

heaviest material (nickel and iron). 4. Brain Pop Earth

Mars

• Mars is called the red planet.• The reddish color is caused by rust (iron oxide) in

the soil.• Most studied planet other than earth.• Mars is a cold planet because of its thin

atmosphere and distance from the sun.• The pressure is so low in the atmosphere that any

liquid water would quickly boil away.• The only water found on Mars is in the form of

ice.• Brain Pop Mars

Mars

• Dry river beds on Mars indicates that there possibly was water in the past.

• Mars now has two polar icecaps that contain frozen water and carbon dioxide.

Asteroid Belt

• The Terrestrial Planets are separated from the Gas Giants by the asteroid belt.

• The asteroid belt lies between Marsand Jupiter.

•Gas Giant

• There are four Gas Giants (outer planets):

• Jupiter

• Saturn

• Uranus

• Neptune

Jupiter• The first of the outer planets.

• Is the largest planet!

• Considered to be a gas giant made mostly of hydrogen and helium.

• Known for its giant red spot.

• This spot has a diameter three times that of earth.

• Jupiter has about 63 moons and a ring system. The four of Jupiter’s natural satellites are Io, Europa, Ganymede, and Callisto.

• Io has active volcanoes, and Europa has the possibility of a water environment friendly to life.

Saturn• The second largest planet in the solar system.

• Saturn gives off a lot of energy caused by helium raining out of the atmosphere and sinking to the core. So… Saturn is still forming!

• The composition of Saturn's atmosphere includes more sulfur. This adds to Saturn's overall yellow appearance.

• Although the gas giants have rings, Saturn’s rings are the largest.

• The rings consist of icy particles that range in size from a few centimeters to several meters across.

Uranus

• Uranus has some of the brightest clouds in the outer solar system and 11 rings.

• No solid surface ; Uranus's interior is primarily made of methane ice.

• One especially unusual quality of Uranus is that it is tipped over on its side.

• The axis of rotation is tilted by almost 90°

• For part of a Uranus year, one pole points toward the sun while the other pole is in darkness.

Neptune• Warm gases rise and the cool gases sink, setting

up the wind patterns in the atmosphere that create the belts of clouds.

• Neptune's winds are three times stronger than Jupiter's and nine times stronger than Earth's.

• Voyager 2 images also revealed that Neptune has a set of very narrow rings (six rings to be exact).

• This hurricane-like 'Great Dark Spot' was observed to be large enough to contain the entire Earth, spun counterclockwise, and moved westward at almost 750 miles per hour.

What about Pluto?

On August 24, 2006, the International Astronomical Union (IAU) formally downgraded Pluto from an official planet to a dwarf planet.

One of the criteria for being an official planet is that a planet must have cleared other things out of the way in its orbital neighborhood.

• Pluto does not meet this criteria.

• Pluto orbits among the icy wrecks of the Kuiper Belt (a region of the Solar System beyond the planets) and Ceres.

• Are made of rock

• Are closer to the sun

• Smaller than the outer planets

• Some have water on them

• Have hard surfaces

• No rings

• Are made of gas

• Are farther from the sun

• Bigger than the inner planets

• No water, but some have ice

• Do not have hard surfaces

• Could have rings

• In our solar system

• Are planets• Separated

by the asteroid belt

• All revolve around the sun