The Future of Earth and the Sun

What will happen to the sun after it exhausts its hydrogen fuel?

• It will turn into a red giant.

• It will remain unchanged.

• It will explode as a supernova.

• It will become a black hole.

Why does the sun get brighter as it ages?

• Because it gains more mass.

• Because it loses its outer layers.

• Because it absorbs energy from nearby stars.

• Because its core temperature and density increase.

What is the faint young sun paradox?

• The sun's brightness decreases as it ages.

• The sun was dimmer in the past, yet Earth was warm enough for life.

• The sun's brightness has always been constant.

• The sun was once much hotter than it is now.

How might Earth's atmosphere have compensated for a fainter sun in the past?

• By having a stronger greenhouse effect.

• By being thicker and more reflective.

• By having less carbon dioxide.

• By containing more oxygen.

What is the Goldilocks zone?

• The region where liquid water can be sustained.

• The region where a planet is too cold for life.

• The region where a planet has no atmosphere.

• The region where a planet is too hot for life.

What will happen to Earth's oceans as the sun continues to brighten?

• They will remain unchanged.

• They will freeze over.

• They will become more acidic.

• They will evaporate completely.

Which type of life form is expected to survive the longest as Earth becomes a desert planet?

• Complex multicellular organisms

• Single-celled extremophiles

• Marine animals

• Plants using C3 photosynthesis

What is a possible consequence of increased atmospheric water vapor on Earth?

• It will cause the atmosphere to become more stable.

• It will cool the planet significantly.

• It will lead to more frequent rainstorms.

• It will enhance the greenhouse effect, speeding up ocean loss.

What is one potential method to mitigate the effects of the sun's increasing brightness on Earth?

• Seeding the atmosphere with reflective nanoparticles

• Building a giant mirror in space

• Increasing Earth's rotation speed

• Moving Earth to a different orbit

How might Mars benefit from the sun's increasing brightness?

• It will gain a magnetic field.

• Its ice reserves may thaw, releasing water.

• It will develop a thick atmosphere.

• It will become a new home for Earth's plants.