The solar system

Where is our solar system found?

milky way

What are the eight natural satellites called planets that orbit the sun (from closest to furthest)?

• mercury

• venus

• earth

• mars

• jupiter

• saturn

• uranus

• neptune

What also orbits the sun?

dwarf planets like pluto

What are natural satellites that orbit some planets?

moons

what is an example of a man made satellite?

the international space station

What are the terrestrial (rocky) planets?

• mercury

• venus

• earth

• mars

What are the jovian (gas) planets?

• jupiter

• saturn

• uranus

• neptune

What separates the terrestrial and jovian planets?

the asteroid belt

What belt is beyond the jovian planets?

Ruiper belt

How is a star formed?

1. disc of dust and gas rotates

2. cloud of dust and gas is drawn inward by gravity

3. the temperature in the centre becomes hotter

4. a protostar is formed

5. fusion takes place

6. the star begins to shine

Stage 1 of birth of a star

• clouds of dust, rock and gas exist in a planetary nebula

• gas is drawn inwards by gravity and clumps begin to form

• the collapsing cloud begins to rotate and flatten into a disc of gas and dust

Stage 2 of birth of a star

• the disk rotates faster and faster pulling more material inwards

• the particles collide more often the temperature increases in the centre

• a hot dense core called a protostar is created

Stage 3 of birth of a star

• when the protostar becomes hot enough hydrogen atoms begin to fuse producing helium

• energy is released

• the star begins to shine

Stage 4 (Sun & solar system) star formation

• in the formation of the solar system the sun is the star at the centre

• the heat from the sun evaporates any ice in the cloud

• it pushes away the gas leaving clumps of rock orbiting close to the sun

Stage 5 (Sun & solar system) star formation

• the clumps are not hot enough to become protostars

• but go on to form planets or if smaller asteroids orbiting the star

• our sun has 4 inner rocky planets and four outer gas giants orbiting it

• with an asteroid belt between mars and jupiter

Stage 6 (Sun) star formation

• eventually radiation pressure pushing outwards from fusion reaction in thestar or in our sun is equal to gravity pulling inwards

• the forces are balanced and the star is stable it will remain the same size

• it is a main sequence star

At what stage is our sun in at the moment?

main sequence star

What forces are acting on the sun when its a main sequence star? (2)

• gravity and radiation are equal

• radiation inwards and gravity outwards

How are planets formed? (2)

• rocks, clumps left behind from star formation

• → fusion