Our World, Other Worlds
Test your knowledge of how Earth is different from other planets.
Answer questions like ...
- Earth is called a 'Goldilocks planet' because:
- Which circumstances could end life on Earth?
- Exoplanets that have a lot of volcanic activity and exist in systems with many asteroids are bad prospects for looking for extraterrestrial life.
- Mars once had running water that carved canyons and other features into its surface. What happened to the water?
- Earth and Venus are rocky planets of about the same size, but Earth's average surface temperature is about 59° F, while Venus' is 1,350° F, hot enough to melt lead or aluminum. Why the difference?