Demonstrates how ten hypothetical situations would affect our planet and life on it. Topics include: what if the moon didn't exist, what if earth were tilted li

What if we had two moons? Or if the earth were less dense, or if our solar system were younger? Comins analyzes how differences would affect the plant, animal,

What if Earth had several moons or massive rings like Saturn? What if the Sun were but one star in a double-star or triple-star system? What if Earth were the o

"What if?" questions stimulate people to think in new ways, to refresh old ideas, and to make new discoveries. In What If the Earth Had Two Moons, Neil Comins l