Our Solar System consists of:

• __________

• __________

• __________

• __________

• __________

• __________

1 Star

8 Planets

Many Moons

Asteroids

Comets

5+Dwarf Planets

•The _____ is our nearest star and the

center of our solar system.

•It is a big ball of _________. (92% H / 8% He)

•It is the source for all of the

_________________ in the solar system.

•It has 99.85% mass of the Solar System

sun

gases

light and energy

The SunThe Sun

•The sun has a lot of _______ which pulls on the planets and keeps them in orbit.

•The planets ______________ (travel) around the sun in an elliptical or oval path.

•The amount of time that each planet takes to travel around the sun is known as a ___________ and is the length of a year on that planet.

gravity

orbit or revolve

revolution

RevolutionsRevolutions

Each planet also _______, or spins on its axis, as it revolves around the sun.

The amount of time that each planet takes to turn all the way around its axis is known as a __________ and equals the length of one day on that planet.

rotates

rotation

RotationRotation

In order for an object in the solar system to be considered a planet, it must do 3 things.• It must ______ the sun.• It must have a _______ shape.• It must have cleared its neighborhood.

The planets listed in their order based on how far they are from the sun are:

_________,_________, ______, ________, ________, ________, ________, and _________.

orbitround

Mercury Venus Earth MarsJupiter Saturn Uranus Neptune

PlanetsPlanets

Inner Planets “Terrestrial Planets”

• Rocky

• Dense

• Small

Images: Lunar and Planetary Laboratory: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=178

• Few or no moons• Metal cores (iron)

AsteroidsAsteroids

Asteroids are small objects that orbit the sun. Many are found in the asteroid belt between Mars and Jupiter. Others are found in the Kuiper belt past Pluto.

Outer Planets

• Large!

• Gas Giants

• No solid surface (land masses)

• May have a small solid core

• Tumultuous atmospheres - rapid winds, large storms

• Rotate relatively quickly

• Many moonsImage: Lunar and Planetary Laboratory: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=178

Kuiper Belt

• Disk of debris at the edge of our Solar System

• Pluto is a KB Object (sorry!)

• Source of short-period comets

Comets and the Oort CloudComets and the Oort Cloud

Outside the Kupier Belt is the Oort cloud, a cloud of dust and other objects that orbit our sun. Most comets travel in this cloud in irregular orbits that pass close to the planets.

Inner Planets!

Image: Lunar and Planetary Laboratory: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=178

Mercury – The Hidden PlanetMercury – The Hidden PlanetPlanet Fast facts:

• Diameter – 3031 miles• Distance from Sun -

~36 million miles

• Gravity -1/3 of Earth’s• Rotation (day) -

59 Earth Days

• Revolution (year) - 88 Earth Days

• Atmosphere – almost none• Moons – none• Rings - none

• Named after the Roman messenger God because of how fast it orbits the sun.

• Temperature ranges from 800o F to hundreds of degrees below zero.

• Surface is covered by craters caused by objects smashing into it.

Venus- The Bright PlanetVenus- The Bright PlanetPlanet Fast Facts

• Diameter – 7521 miles• Distance from Sun –

67 million miles

• Gravity -9/10 of Earth’s• Rotation (day) -

243 Earth Days

• Revolution (year) - 225 Earth Days

• Atmosphere – – 96% carbon dioxide

• Moons – none• Rings - none

• Named after the Roman Goddess of Love and beauty.

• It is the brightest object in the sky besides the sun and moon.

• Called Morning or Evening Star depending on its location.

• Atmosphere causes a greenhouse effect so temperatures reach 900oF.

Earth- The Blue PlanetEarth- The Blue PlanetPlanet Fast Facts

• Diameter – 8000 miles• Distance from Sun –

– 93 million miles• Gravity – 1g• Rotation (day) -

1 Earth Day• Revolution (year)

365 Earth Days• Atmosphere –

– 78% nitrogen – 21 % oxygen

• Moons – one : Luna• Rings - none

• Named after the Roman Goddess Ea, which means earth

• It is called the blue planet because of the water that covers 75 % of the surface.

Mars- the Red PlanetMars- the Red PlanetPlanet Fast Facts

• Diameter – 4000 miles• Distance from Sun –

142 million miles

• Gravity – 1/3 of Earth’s

• Rotation (day)– 25 Earth Hours

• Revolution (year)687 Earth Days

• Atmosphere – – 95% Carbon Dioxide

• Moons – two: Phobos & Deimos

• Rings - none

• Temperature ranges from 75F to -190F.

• It has the largest known mountain (volcano) in our solar system called Olympus Mons. It is 3 times taller than Mt. Everest.

• It has a canyon 10 times longer and 3 times deeper than the Grand Canyon.

Deimos

Phobos

•Scientists’ currently think yes there is..

•Possibly lots of water…• •~about 3.5 – 4 billion years ago there may have been an acidic, salty ocean

Image: LPI http://www.lpi.usra.edu/education/timeline/gallery/slide_19.html

Is there Water on Mars?

• Water ice and dust• CO2 layer – winter• Caps expand and

contract during seasonal changes

MGS image of ice cap:http://mars.jpl.nasa.gov/gallery/polaricecaps/PIA02393.html

Viking image at http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vl2_p21873.html

Viking Image at http://photojournal.jpl.nasa.gov/catalog/PIA00407

Martian Water Now

Jupiter – The GiantJupiter – The GiantPlanet Fast Facts

• Diameter – 89,000 miles• Distance from Sun –

– 484 million miles

• Gravity – 2 ½ times Earth’s• Rotation (day) –

10 Earth Hours

• Revolution (year) - 12 Earth Years

• Atmosphere – – Hydrogen and Helium

• Rings – 3 made of fine dust particles

• Moons – 62 with 50 them being named

• The most famous moons are the 4 Galilean moons; Io, Europa, Ganymede and Callisto.

• Ganymede is the largest moon in the solar system and is larger than Mercury.

• The big Red Spot is believed to be a 340 year old storm.

• It is 3 times the size of Earth

Io

Callista

Ganymede

Europa

Saturn – The Ringed PlanetSaturn – The Ringed PlanetPlanet Fast Facts

• Diameter – 75,000 miles• Distance from Sun –

890 million miles

• Gravity – slightly more than Earth’s

• Rotation (day)– 10 ½ Earth Hours

• Revolution (year)29 ½ Earth Years

• Atmosphere – – Hydrogen, – Helium – Methane

• Moons:has 62

53 named

• Titan is largest & has atmosphere.

• Rings – 7 rings, made of smaller ice ringlets

• Saturn’s average density is less than water, so it would float.

• Like Jupiter, Saturn gives off more heat than it receives from the sun

Saturn

Titan and smaller moon looking across Saturn’s rings.

Titan’s Cloudy suface

Uranus – the Tilted PlanetUranus – the Tilted Planet

Planet Fast Facts

• Diameter – 32,000 miles• Distance from Sun –

– 1,800 million miles

• Gravity – 9/10 of Earth’s

• Rotation (day) – 18 Earth Hours

• Revolution (year)84 Earth Years

• Atmosphere – – 72 %Hydrogen

– 26% helium

– 2% methane

• Moons – 27 known natural satellites

• Rings -11made of ice boulders and fine dust

• Its axis is tilted 98o, which means it lays on its side. It rotates like a ball rolling across the floor rather than like a top.

The moons of Uranus are not named after Roman mythological characters. They are named after characters from the writings of Shakespeare and Alexander Pope.

Neptune – The Twin PlanetNeptune – The Twin PlanetPlanet Fast Facts

• Diameter – 31,000 miles• Distance from Sun –

– 2,800 million miles

• Gravity – slightly larger than Earth’s

• Rotation (day)– 19 Earth Hours

• Revolution (year)168 Earth Years

• Atmosphere – – Hydrogen – Helium – Methane

• Moons- 13 known satellites The largest is the moon, Triton. Triton orbits Neptune in the opposite direction from the planet’s rotation.

• Rings- 3 obvious rings and one faint ring made of dust

• Scientists knew Neptune existed before they saw it because of its effect on Uranus’ orbit

Neptune

Triton

Dwarf PlanetsDwarf Planets• These are small bodies that orbit the sun and

have nearly round shapes as a result of their own gravity and are not satellites.

• There are 6 known dwarf planets, Pluto, Ceres, Makemake, Haumea, Quaoar and Eris.

• Scientists are studying about 200 more objects in the solar system that may be classified as dwarf planets.

Pluto

Charon

PlutoPluto• Pluto was once

known as the 9th planet.

• Its orbit passes into the Kupier belt which means the orbit is not clear of other objects. That is why it is a dwarf planet.

Its three moons are Charon, Nix and Hydra.

CeresCeres

• Ceres is located in the asteroid belt between Mars and Jupiter. It was discovered in 1801 and has a diameter of 950 km.

• It orbits the sun every 4.6 years. It has water and an atmosphere.

• It has 1/3 of all the mass in the asteroid belt.

ErisEris

• Discovered in 2005.

• Larger than Pluto

• 3 times as far from the sun as Pluto

• Has a moon named Dysnomia

Haumea

• Just farther from the sun than Pluto

• Icy world

• Elliptical in shape

• Revolution 285 years

• Rotation 4 hours

• Two moons – – Hi’iaka & Namaka

Makemake

• Orbits past Pluto

• Revolution – 310years

• Red in color

• Diameter = 1300 km

Comparing the PlanetsComparing the Planets

The Milky WayThe Milky WayOur solar system is in the Orion arm of a

spiral galaxy known as the Milky Way.

GalaxyGalaxy

• A galaxy is a collection of stars, interstellar gases, dust and dark matter.

• Galaxies are classified based on their shapes. There are three main types.– Elliptical– Spiral – Irregular

Elliptical Elliptical GalaxyGalaxy

Spiral GalaxySpiral Galaxy

Irregular GalaxiesIrregular Galaxies

Colliding GalaxiesColliding Galaxies

It is believed that the universe is expanding and galaxies are moving. Scientist have taken pictures of colliding galaxies to prove this.

StarsStars• Inside galaxies are 100’s, 1000’s or

1,000,000’s of stars.

• Not all stars are the same.

• Stars are classified by their colors. They are red, orange, yellow, white and blue. The color indicates how hot a star is with red being the least hot and blue being the hottest.

• Our sun is a medium sized yellow star.

Star comparisonsStar comparisons

Is Pluto a Planet?

• is in orbit around the Sun,

• has sufficient mass for its self-gravity so that it assumes

a spherical shape

• has cleared the neighborhood around its orbit.

What Makes a Planet a Planet?

Is Pluto a Planet?

• is in orbit around the Sun,• has sufficient mass for its self-gravity so that it assumes a spherical shape• has NOT cleared the neighborhood around its orbit• is not a satellite (MOON)

• a dwarf planet is not a planet!

What is a Dwarf Planet?

Is Pluto a Planet?

Image based on NASA images, from http://en.wikipedia.org/wiki/Image:EightTNOs.png

Pluto is not a planet because it is way too small, and it doesn't meet the necessary requirement needed to be a planet.

The requirements are:

It needs to be in orbit around the sun-- YES! Pluto does orbit the sun.

It needs to have enough gravity to pull itself into a spherical shape -- Pluto has sufficient gravity to have become a shpere. (This is called hydrostatic equilibrium, by the way.)

It needs to have ”cleared the neighborhood_" of its orbit -- Uh oh. Here's the "problem" with Pluto. According to this IAU rule, Pluto is not a planet.