life cycle of a star Flashcards
1
Q
What is a protostar?
A
dust and gas spiralled together
2
Q
how does a main sequence star form?
A
- temperature rises and hydrogen nuclei undergo nuclear fusion to form helium nuclei and give out a massive amount of light and heat
- gravity pulls everything inwards and the star enters a long stable period
3
Q
how is a red giant and a super red giant formed?
A
- the hydrogen runs out
- the star (if small) swells to a red giant or (if big) super red giant
- it is red because the surface cools
4
Q
how is a supernova formed?
A
big stars undergo more fusion and expand, they eventually explode in a supernova
5
Q
how is a neutron star or black hole formed?
A
the exploding supernova throws outer layers of dust and gas into space leaving a dense core (neutron star) and if the star is huge a black hole
6
Q
how is a white dwarf made?
A
the red giant leaves behind a hot, dense solid core ( a white dwarf) that cools to a black dwarf and disappears
