THE SOLAR SYSTEM

The solar system

• Formed 4.6 billion years ago from a nebula• a cloud of dust and gas• The hot center from

this nebula, shrinking and spinning, formed the sun

• Left over dust and gas formed planets around the sun

THE SUN

– Hot ball of gas or a big star

– It’s gravity holds objects together in the solar system

• Stops planets from flying off into space, keeps them in line of orbit

THE SUN

• Diameter = 1.4 km• 27 million degrees

Fahrenheit• Large enough to hold 1

million Earth’s • More information is in

your textbooks on page D40

PLANETS: Large, round bodies that revolve around a star

Terrestrial Planets

• made mostly of rock

Mercury

Venus

Earth

Mars

Jovian Planets

• a gas giant planet• does not consist of solid or rock

Jupiter

Saturn

Uranus

Neptune

Order of the Planets

• My Mercury• Very Venus• Energetic Earth• Mother Mars• Just Jupiter• Served Saturn• Us Uranus• Noodles Neptune

Can you think of your own?

PLUTO??

• In the Kuiper Belt • made mostly of ice and

rock

• Too small to be a planet, but known as a dwarf planet• massive and has own

gravity• has not cleared the

neighborhood around its orbit

STARS

• Massive balls of plasma

• Constellation: formation of stars

• Nearest star to Earth– Sun

• Most stars 1 – 10 billion years old

ASTEROIDS

• Rocky objects between Mars and Jupiter

• Too small to be a planet – hypothesis that failed to

be a planet• Giant chunks of rock that

look like giant potatoes in space

• Some are the size of planets, others are the size of a basketball

COMETS

• Ice chunks that spin close to the sun• Glowing clouds surround most comets, and

tails of gas can often be seen trailing them as their orbits take them near the sun

GALAXIES

• Billions of stars together• Stars, gas, dust, and dark matter