Topic 8 Space Physics Flashcards
What are moons a type of?
Natural satellite
What do stars initially form from?
Cloud of dust and gas called nebula
What are the 6 stages of the lifecycle of a star the size of our sun?
Nebula
Protostar
Main sequence star
Red giant
White dwarf
Black dwarf
What are the 6 stages of the lifecycle of a star much larger than the sun?
Nebula
Protostar
Main sequence star
Red super giant
Supernova
Neutron star/black hole
How is a protostar formed?
Cloud of dust and gas (nebula) pulled together by force of gravity
Describe what happens inside a protostar?
Temperature rises as star gets denser and more particles collide, hydrogen nuclei undergo nuclear fusion, form helium nuclei, gives out lots of energy
Why does a star enter a long stable period as a main sequence star?
Outward pressure caused by nuclear fusion that expands star balances force of gravity pulling inwards
Why does a main sequence star form a red giant/red super giant?
Hydrogen runs out
What happens inside a red giant/red super giant?
Fusion of helium (+ other elements), heavier elements (up to iron) created in core
How does a red giant form a white dwarf?
Becomes unstable, ejects outer layer of dust and gas, leaves hot dense solid core
How does a white dwarf form a black dwarf?
Cools, emits less and less energy
How does a red super giant form a supernova?
Undergoes more fusion, explodes in supernova
Where are elements heavier than iron produced?
Supernova
How are all naturally occurring elements distributed throughout the universe?
Explosion of massive star (supernova)
How does a supernova form a neutron star/black hole?
Exploding supernova throws out layers of dust and gas, leaving dense core
If star massive enough, black hole
What provides the force that allows planets and satellites to maintain their circular orbits?
Gravity
What is the rule for an object in stable orbit?
Radius of its orbit must change if its speed changes
