Space

Question 1

1st stage in lifecycle of stars

Answer 1

Nebulae
Gravity pulls dust and gas together
gravitational energy => heat energy

Question 2

2nd stage in lifecycle of stars

Answer 2

protostar
gravity pulls in dust+ gas to form stars
smaller masses may also form to become planets
gravitational energy=> heat energy
temp rises further

Question 3

3rd stage of star lifecycle

Answer 3

main sequence star
stable period, lasts about 10 billion years
when temp is high enough, fusion reactions start
gravitational forces acting inwards
outward forces from fusion reactions
forces balanced so star stays same size

Question 4

why do stars stay the same size

Answer 4

gravitational forces acting inwards
outward forces from fusion reactions
forces balanced so star stays same size

Question 5

What is the fourth stage in a small star’s lifecycle?

Answer 5

red giant
hydrogen begins to run out
star expands (like 10 times larger) and surface becomes red as it cools

Question 6

what is the fifth stage in a small star’s lifecycle?

Answer 6

white dwarf
star cools and contracts under its own gravity becoming very dense
eventually becomes so cool it fades and becomes a black dwarf

Question 7

what is the fourth stage in a large star’s lifecycle?

Answer 7

red supergiant
after all the hydrogen in a giant star’s core has been used up they become red supergiants with very cool surface temp
these are the largest stars