Rotation=SpinningRotation=Spinning

Revolution = OrbitRevolution = Orbit

The Inner The Inner PlanetsPlanets

The Inner PlanetsThe Inner Planets Have no ringsHave no rings Only 0-2 moons Only 0-2 moons

eacheach Prograde rotationPrograde rotation: :

looking down from looking down from the top of the the top of the planet, it moves planet, it moves counterclockwise, counterclockwise, from left to rightfrom left to right

Retrograde rotationRetrograde rotation: : moves clockwise, moves clockwise, from right to leftfrom right to left

The Inner PlanetsThe Inner Planets

Planets made of Planets made of solid rocksolid rock

Have impact cratersHave impact craters

Surface of Mars

Mercury

MercuryMercury

Closest to the sunClosest to the sun Sun’s light obscures it from viewSun’s light obscures it from view

Mercury

MercuryMercury

Shortest Revolution: 88 daysShortest Revolution: 88 days Takes 59 days to spin once (rotate)Takes 59 days to spin once (rotate) Has no moonsHas no moons

MercuryMercury

Very thin Very thin atmosphereatmosphere So close to sunSo close to sun Very weak gravityVery weak gravity

Is heavily crateredIs heavily cratered Huge temperature Huge temperature

rangerange 427°C during day427°C during day -173°C at night-173°C at night

VenusVenus

Second planetSecond planet 225-day orbit225-day orbit Rotates slowly: Rotates slowly:

243 days to spin 243 days to spin onceonce

RetrogradeRetrograde Has no moonsHas no moons

VenusVenus

The earth’s twinThe earth’s twin Almost same mass, size, and densityAlmost same mass, size, and density

VenusVenus

Very hotVery hot Close to the sunClose to the sun Very thick Very thick

atmosphere, 96% atmosphere, 96% Carbon DioxideCarbon Dioxide

EarthEarth

Third planetThird planet 365.24 days to 365.24 days to

make one make one revolution (orbit)revolution (orbit)

One rotation; 23 One rotation; 23 hours and 56 hours and 56 minuteminute

Volcanically activeVolcanically active Has 1 moonHas 1 moon

EarthEarth

Life existsLife exists Water presentWater present Ideal temperatureIdeal temperature Oxygen and COOxygen and CO22

MarsMars

Fourth planetFourth planet 687 days to orbit687 days to orbit One rotation: 24 One rotation: 24

hours, 37 minuteshours, 37 minutes Same tilt as Earth’s Same tilt as Earth’s

axisaxis

MarsMars

Volcanically activeVolcanically active Largest volcano in Largest volcano in

solar system- solar system- Olympus MonsOlympus Mons

Has two moonsHas two moons

MarsMars

Currently frozen Currently frozen water is at poles water is at poles and liquid may be and liquid may be under the surfaceunder the surface

No solid evidence No solid evidence of life on Marsof life on Mars

Asteroid BeltAsteroid Belt

Rocks left over Rocks left over from the formation from the formation of the solar systemof the solar system

Located between Located between Mars and JupiterMars and Jupiter

50,000-1,000,000’s 50,000-1,000,000’s asteroids existasteroids exist

The Outer The Outer PlanetsPlanets

The Jovian PlanetsThe Jovian Planets

Also known as the Also known as the Gas Gas GiantsGiants

Large and MassiveLarge and Massive Less denseLess dense than the than the

inner planetsinner planets Atmospheres of mostly Atmospheres of mostly

hydrogen and helium hydrogen and helium gasgas

Probably have a solid Probably have a solid corecore

JupiterJupiter Largest planet in Largest planet in

the solar systemthe solar system Twice the mass of Twice the mass of

all other planets all other planets combinedcombined

Extremely hot in Extremely hot in the interiorthe interior

If Jupiter had been If Jupiter had been larger, it could larger, it could have become a starhave become a star

JupiterJupiter

Revolution= 12 Revolution= 12 yearsyears

Fastest rotation in Fastest rotation in the solar system= the solar system= 9 hrs, 50 min9 hrs, 50 min

Jupiter

Venus

JupiterJupiter

Has at least 17 Has at least 17 moons and 4 ringsmoons and 4 rings

The Great Red The Great Red Spot on Jupiter is a Spot on Jupiter is a giant stormgiant storm

SaturnSaturn

Fast rotation=10 hours, 30 minutesFast rotation=10 hours, 30 minutes Revolution= 29.5 yearsRevolution= 29.5 years

SaturnSaturn

At least 18 moons,At least 18 moons, several complex several complex ringsrings

Saturn is the least Saturn is the least dense planet, less dense planet, less dense than waterdense than water

UranusUranus

Orbit period= 84 Orbit period= 84 yrsyrs

Rotates once every Rotates once every 17 hours17 hours

Rotates like a Rotates like a rolling ballrolling ball

UranusUranus

At least 20 moons At least 20 moons and 11 small ringsand 11 small rings

Greenish color Greenish color indicates methane indicates methane gasgas

NeptuneNeptune

Orbit period = 164 Orbit period = 164 yrsyrs

Rotates every 16 Rotates every 16 hrshrs

Bluish colorBluish color, , named after the named after the Roman god of the Roman god of the seasea

NeptuneNeptune Has Has eight moons and maybe four ringseight moons and maybe four rings The Great Dark Spot is a giant stormThe Great Dark Spot is a giant storm

Kuiper BeltKuiper Belt

The The Kuiper beltKuiper belt is a disk-shaped is a disk-shaped region past the orbit of region past the orbit of NeptuneNeptune containing many small icy bodies. It containing many small icy bodies. It is now considered to be the source is now considered to be the source of the short-period of the short-period cometscomets..

Oort CloudOort Cloud

The outermost part The outermost part of our solar systemof our solar system

The origin of most The origin of most cometscomets

PlutoPluto Smallest planet in the solar systemSmallest planet in the solar system 1 rotation= 6 days1 rotation= 6 days

PlutoPluto

250 year revolution250 year revolution Pluto’s orbit is ellipticalPluto’s orbit is elliptical Sometimes closer to the sun than Sometimes closer to the sun than

NeptuneNeptune

PlutoPluto

Pluto has one Pluto has one moon, half its sizemoon, half its size

Pluto is the largest Pluto is the largest object in the object in the Kuiper BeltKuiper Belt

Formation of the Solar SystemFormation of the Solar System

Pluto may not be a planet at all, but just a large Pluto may not be a planet at all, but just a large object in the object in the Kuiper belt that surrounds our Kuiper belt that surrounds our solar systemsolar system

Formation of the Solar Formation of the Solar SystemSystem

The Kuiper belt, The Kuiper belt, discovered in discovered in 1992, is made of 1992, is made of cold, icy cold, icy planetesimals that planetesimals that never collided with never collided with each other to form each other to form a planeta planet

Pluto is the largest Pluto is the largest object in the object in the Kuiper BeltKuiper Belt

Short Period Comet