Unit 4 - Our Universe

Front

What is a super giant star?

Back

A super giant star is a massive star that is very bright and can be cool in temperature.

Front

What happens to a star when it runs out of hydrogen?

Back

It expands and cools, becoming a red giant.

Front

What force causes dust particles to stick together in a nebula?

Back

Gravity is the force that causes dust particles to stick together in a nebula.

Front

What type of galaxy is characterized by spiral arms?

Back

A spiral galaxy is characterized by its spiral arms.

Front

What happens to stars as we move to the left on the Hertzsprung-Russell diagram?

Back

Stars get hotter as we move to the left.

Front

Define a red giant star.

Back

A red giant star is a star that has expanded and cooled after exhausting its hydrogen fuel.

Front

What is the main force that holds galaxies together?

Back

Gravity is the main force that holds galaxies together.

Front

What is a pulsar?

Back

A pulsar is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation.

Front

What is a black hole?

Back

A black hole is a region of space where the gravitational pull is so strong that nothing, not even light, can escape from it.

Front

What is a supernova?

Back

A supernova is a powerful and luminous explosion of a star that occurs at the end of its life cycle.