10 minutes maximum! Can you do it in 5?

1. The Sun and all stars generate heat and light by..

  • A. nuclear fusion
  • B. nuclear fission
  • C. combustion of fuels
  • D. thermal ignition
2. Most stars visible in the sky are stable. The inwards forces balance the outward forces. Which answer below best describes what causes these forces?  
Inwards force Outward force
Gravity Pressure from heat caused by fusion
Collapse as light elements form heavier, more dense ones Pressure from heat caused by fusion
Gravity Pressure from combustion of fuels
Collapse as light elements form heavier, more dense ones Pressure from combustion of fuels

3. Which element is found in all main sequence stars and is responsible for the heat generated by nuclear fusion?

  • A. Oxygen
  • B. Hydrogen
  • C. Helium
  • D. iron
Stars like the Sun The Sun

4. The Sun is currently in the main sequence of its evolution. What will happen to the Sun immediately after it evolves beyond this stage?

  • A. It willl become a black hole
  • B. It willl become a red giant
  • C. It willl become a white dwarf
  • D. It willl become a supernova

5. In billions of years time, the Sun will no longer have the elements required for fusion reactions and will be a very small and dense object, but still very hot.

What is this stage called?

  • A. A nebula
  • B. A neutron star
  • C. A supernova
  • D. A white dwarf
Very Large Stars  

6. Very large main sequence stars are typically much hotter than the Sun, as indicated by their colour. Which of the star colours below has the highest temperature?

  • A. A red star
  • B. A blue star
  • C. An orange star
  • D. A yellow star

7. Very large stars like this will eventually explode in a massive fusion reaction. This stage is called a ...

  • A. white dwarf
  • B. neutron star
  • C. supernova
  • D. big bang

8. The explosion forms a new cloud of lighter and heavier elements. A cloud like this in space is called a ...

  • A. nebula
  • B. galaxy
  • C. milky way
  • D. protostar

9. The remaining core of the star contracts as gravity pulls it inwards. For many heavy stars, this stops when incredibly dense and made of sub-atomic particles. These stars are called ...

  • A. black holes
  • B. neutron stars
  • C. white dwarf stars
  • D. black dwarf stars

10. For the heaviest stars in the Universe, when the core collapses inwards the final stage of evolution is a ...

  • A. black hole
  • B. neutron star
  • C. white dwarf star
  • D. black dwarf star