space - the lifecycle of stars Flashcards
1
Q
where do stars begin
A
as a nebula - cloud of dust and gas
2
Q
what causes the formation of a protostar
A
the nebula collapses due to gravity meaning the particles move faster increasing the temperature and forming a protostar
3
Q
hydrogen nuclei join to form
A
helium nuclei
4
Q
what is the star called at this point
A
a main sequence star
5
Q
how long are stars in the main sequence for
A
a very long time
6
Q
what happens to stars the same size as out sun
A
- the star collapses inwards
- the temperature increases
- helium nuclei fuse together to make heavier elements
- the star expand to form a red giant
- the star shrinks to form white dwarf
- the star cools, and stops releasing energy forming a black dwarf
7
Q
what happens to stars bigger then the sun
A
- expand int red super giants
- helium nuclei fuse together to produce heavier elements
- the tsar explodes - supernova
- temperature is high enough to produce elements heavier then iron
- elements gets distributed
- supernova forms either a neutron star or black hole
