a star which is fusing hydrogen in its core; these stars are stable for long periods of time

a larger, cooler, star formed after hydrogen in the core has been depleted

the white hot core of a star after its outer layers have escaped into space

an exploding star, caused by a gravitational collapse after the fuel is exhausted

an incredibly dense star, formed after a supernova

Stellar evolution

Physics

The solar system

Orbital motion of artificial satellites

Birth of a star

Observing the universe

The changing universe

In the Solar system and beyond unit, pupils learnt about the scale and content of the Solar system and the universe, and about gravitational force and the motions that cause days and seasons on the Earth.

This unit covers the solar system's features, including planets, moons, and satellites. It explains gravity's effect on orbits, the sun's formation from dust and gas, and fusion equilibrium. It also explores red-shift, evidence of an expanding universe, and the link to the Big Bang model.

Gravity in space

What is the main type of nuclear reaction that takes place in the core of a star?

for about the same time as average-sized stars

for much less time than average-sized stars

How long are very large stars **main sequence stars** for, compared to average-sized stars?

increased temperature throughout the star from hydrogen fusion

increased temperature in the core of a star from hydrogen fusion

increased temperature throughout the star from helium fusion

increased temperature in the core of a star from helium fusion

What causes a star to expand into a red giant star?

What type of star forms from the core of a red giant star after its outer layers have been lost?

its gravitational force is big enough to hold onto its outer layers

its outer layers escape very slowly into space

its outer layers escape fairly rapidly into space

its outer layers are blasted off into space in an explosion

What happens to the outer layers of a red supergiant star?

What can form from the core of a red supergiant star after its outer layers have been lost in a **supernova** explosion?

a huge ball of very hot gas and plasma that is burning

a huge ball of very hot gas and plasma with a burning core

a ball of very hot gas and plasma with nuclear fission reactions in its core

a ball of very hot gas and plasma with nuclear fusion reactions in its core

small nuclei combine to form bigger nuclei of the same element

small nuclei combine to form bigger nuclei of a different element

large nuclei split to form smaller nuclei of the same element

large nuclei split to form smaller nuclei of a different element

What happens in a nuclear fusion reaction?

What is a region of space called that contains traces of hydrogen gas and very fine dust?

a huge ball of dense, hot gas with nuclear fission reactions in its core

a huge ball of dense, hot gas with nuclear fusion reactions in its core

What type of nuclei (which element) is fused together in nuclear reactions in the core of a new star? 

What type of star fuses hydrogen in its core?

Exit Quiz

What is the main type of nuclear reaction that takes place in the core of a star?