Subscribe now

Space

How many moons and moonmoons could we cram into Earth's orbit?

Earth is lagging behind other worlds with its single moon, so on this episode of Dead Planets Society we are giving it more – and giving those moons moonmoons to orbit them

By Leah Crane and Chelsea Whyte

11 June 2024

Dead Planets Society is a podcast that takes outlandish ideas about how to tinker with the cosmos – from snapping the moon in half to causing a gravitational wave apocalypse – and subjects them to the laws of physics to see how they fare. Listen on Apple, Spotify or on our podcast page.

One moon simply isn’t enough. Earth only has one, while some other planets have many – Jupiter has 95 moons, putting our single shining cosmic partner to shame. In this episode of Dead Planets Society, it’s time to light up the night sky with as many moons as possible.

But it isn’t as easy as just chucking a bunch of rocks into orbit, so our hosts Leah Crane and Chelsea Whyte are joined this episode by Sean Raymond at the University of Bordeaux in France for help with the particulars. He suggests we could construct a ring of 10 moons orbiting Earth, each in a different phase, causing strange little eclipses as they march around the planet.

And it isn’t just moons: in 2018, Raymond and Juna Kollmeier at Carnegie Observatories in California found it is theoretically possible for Earth’s moon to have its own orbiting satellite, dubbed a moonmoon. Such a thing might not be stable because of gravitational anomalies present in our moon, so our hosts are adding a gargantuan immersion blender to their cosmic toolbelt to smooth things out. Once things are sorted, there could be moonmoons and even moonmoonmoons lighting up the night sky.

The moon is bright because it reflects sunlight, and these new moons could be the perfect places to put a series of huge solar panels – unobstructed by the atmosphere and clouds that plague Earth’s surface. They would also be so bright it would probably be impossible to ever see the stars from Earth’s surface, but that’s a relatively small detail.

The bigger problem: the more complex and crowded the orbits get, the greater the risk of these moons and moonmoons smashing together. This could give our planet beautiful rings like Saturn’s, but it could also destroy life on Earth.

Dead Planets Society is a hilariously destructive podcast about the cosmos from New Scientist. In each episode, hosts Leah Crane and Chelsea Whyte explore what would happen if they were given cosmic powers to rearrange the universe. They speak with astronomers, cosmologists and geologists to find out what the consequences would be if we punched a hole in a planet, unified the asteroid belt or destroyed the sun. Season two of Dead Planets Society is available to listen on Apple, Spotify, or or on our podcast page.

Sign up to our Launchpad newsletter

Voyage across the galaxy and beyond with our space newsletter every month.

Topics:

Sign up to our weekly newsletter

Receive a weekly dose of discovery in your inbox! We'll also keep you up to date with New Scientist events and special offers.

Sign up