As a science fiction writer, I spend a lot of time thinking about what life on other worlds might be like. For Earth Day, let’s celebrate our special Earth by imagining how different life would be on an “average” planet.
Night and day. The planets near the sun have long, long, days and nights, due to tidal forces. On Venus, the time from sunrise to sunrise is 117 Earthdays long. On Mercury, it’s 176 Earthdays! If Earth were tidally locked to the sun in a 3:2 ratio like Mercury, your home might bake under the sun for months at a time, only to be followed by freezing during months of night. Earth’s rapid rotation is what keeps most of our planet’s land surface livable.
How did we get so lucky? Possibly because of a primordial collision billions of years ago that created the moon!
Sideways. Can you imagine Earth without winter or summer? No seasonal weather changes, no autumn fall of leaves, no spring rebirth of flowers, no yearly migration of birds and animals. The areas around our north and south poles would be less livable, because they’d never warm up.
Most planets don’t have seasons. We only experience seasons because Earth is tilted on its axis—maybe thanks to that old collision. On a planet without seasons, you might have no way to count the years, because every day would be like every other!
Moonstruck. Many planets have moons, but most moons are tiny in comparison to their planet. Earth’s companion Luna is nearly planet-sized, a full quarter of Earth’s size. Without a huge moon like Luna, our nights would be darker. We wouldn’t have the tides that nurture a large portion of Earth’s sea life.
We count time in months and weeks because our ancestors counted time by watching the phases of the moon. On a planet without a moon, how would you count time?
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I had a lot of fun playing around with what it might be like to live on another planet’s moon in my book Fugitive. Check it out along with my other books at KathrynHoffBooks.com, and subscribe for a free sample of Project Hannibal.