Stars Flashcards
How are stars formed?
Gravity pulls clouds of dust, gas and rock together
As the mass comes together , heat is created
This heat begins nuclear fusion
What is a star’s source of energy?
Hydrogen
How does a star remain stable?
The outward force of radiation equals the inward force of gravity
Why can stars give out energy for billions of years?
They have an abundance of hydrogen in their core
What is our galaxy called?
Milky Way
How many galaxies are there in the universe?
Billions
What will happen to stars the same size as our sun when it comes to the end of its life?
Expand to become red giant
Cools to become white dwarf
What will happen to stars at least 4 times as big our sun when it comes to the end of its life?
Expand to become red super-giants
Rapidly shrinks and explodes - supernova (where heavier elements are dispersed across the universe)
What remains after a supernova?
A neutron star (extremely dense)
What form when stars greater than 10 times our sun die?
A black hole is created - nothing can escape from it
What is the product of nuclear fused hydrogen?
Helium
Sometimes, hydrogen and helium fuse together to form…
elements all the way up to iron
The elements dispersed from a supernova are…
recycled to make new stars and planets
