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12 Cards in this Set

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How many planets are their in the solar system?

8- inner planets~ mercury, Venus, earth, mars.
Then the asteroid belt
Outer planets- jupiter, Saturn, Uranus, Neptune.
What are the circular paths the planets take round the sun called?
Other than planets and the sun what else in in the solar system?
Dwarf planets e.g. Pluto, comets, dust, ect these orbit the sun. Planets often have moons orbiting them.
How much bigger is the sun than the earth?
100 times bigger
How can you see stars if they do not emmit light like the sun?
The suns light reflects off them!
How old is the solar system?
5 thousand million years ago or 5 billon years ago.
What was the solar system formed from?
Big clouds of dust and gas.
Explain the process that formed our solar system.
Dust and gas some got squeezed the gravity collected the particles together until it became so heavy they started to collapse in. At centre a protostar formed. Temp rose. Fusion started. Lots of heat and light. Some elements clump together to form planets
What is the first stage of nuclear fusion?
Hydrogen collide to form helium releasing lots of energy.
What are comets made of?
Rock dust and ice.
How are all the chemical elements with heavier atoms than helium or hydrogen were formed how?
In the stars by fusion of different nuclei.
What are the oldest rocks on earth?
Meteorites.(rocks from space that crashed into earth formed not long after the birth of the solar system around 4500 million years old).