Life cycle of stars Flashcards
How does a star begin
As a nebula, a cloud of dust and gases including a lot of hydrogen
how does the materials in a nebula come together
the masses cause them to come together and form a more dense clump of material
What happens as the cloud contracts
the hydrogen becomes hotter and denser
gravitational pull strengthens
turns into a protostar
What happens when the hydrogen fusion occurs
releases a lot of EM radiation outwards
the outward pressure is equal to the gravitational pull
the star is now in its main sequence of its life
what happens to a main sequence star when most of its hydrogen has fused
the core is not hot enough to withstand the gravitational pull and it collapses.
the outer layer expands to form a red giant
what happens inside a red giant
Helium fusion occurs to form heavier elements
how long does a star remain a red giant
it remains a red giant for about a billion years before throwing off a shell of gas.
What happens to a red giant after the shell of gas is thrown off
The rest of the star collapses in on itself to become a white dwarf. No fusion reactions occur inside a white dwarf for about a billion years until it cools down and becomes a black dwarf
Massive star
Main sequence - Massive main sequence
Red giant - Red supergiant
What happens to a red supergiant after its time
the star rapidly collapses and explodes in a supernova
What happens after the supernova of a massive star
If what is left of the star is 4x more the mass of the Sun, gravity pulls the remains together to form black hole
If not, gravity pulls remains together to form a small dense star called neutron star
Black hole
Gravitational pull of a black hole is so strong not even light can escape it
