What is a nebula?
A cloud of dust and hydrogen gas
A collection of billions of stars
A solar system
What causes dust and gas to pull together and form a protostar?
Electrostatic attraction
The Big Bang
Gravitational attraction
Which two balance and keep a main sequence star in equilibrium?
Gravity and friction
Gravity and air resistance
Gravity and radiation pressure
What is nuclear fusion?
The melting of solid metals
Light atomic nuclei combining to form larger nuclei, releasing energy
Heavy atomic nuclei splitting to form smaller nuclei, releasing energy
Where do elements heavier than iron form?
In supernovae
In nuclear fusion in main sequence stars
In the Big Bang
What will the Sun become in the next stage of its life?
A red giant
A red supergiant
A black hole
What happens when a white dwarf cools completely?
It stops emitting light and becomes a black dwarf
It stops emitting light and becomes a neutron star
It stops emitting light and becomes a black hole
Which type of star has supernova explosions?
Stars similar in size to our Sun
Stars much bigger than our Sun
All stars go through a supernova explosion
What sort of reaction mainly happens in the Sun?
Nuclear fission
Nuclear fusion
Chemical
Which of the following suggests that the solar system is made from the debris of old supernova explosions?
The Sun is a relatively small mass star
The Sun is mostly hydrogen
There is gold in the ground on Earth