Just How Deep Is Our Dust from Space?

By Jim Brace-Thompson

Are you frustrated by how much dust builds up inside your home? Frustrated by endless sweeps with dust mitts, vacuums, and feather dusters? Frustrating, indeed! But if you think you have it bad inside your home, consider outside and the entire surface of our home planet Earth.

It has long been known that meteors streaking through our skies shed a shower of extraterrestrial dust while burning up in the atmosphere. Our planet also receives a healthy dusting from the tails of comets. But just how much of a dusting do we receive from meteors, asteroids, comets, ancient planetary fragments, and other sources hanging out in space?

A new study reported in Earth & Planetary Science Letters by Jean Duprat (Sorbonne University, Paris) and colleagues suggests thousands of metric tons!

This estimate is based upon micrometeorites collected from the frozen continent of Antarctica. After digging deep down, Duprat and colleagues collected huge amounts of pure snow and ice. From that, they collected a truly tiny amount of meteorite dust. Tiny as it was, this sample was enough to use in extrapolating the total “dust fall” across the entire Earth surface.

The result at the tail end of their equations? No less than 5,200 metric tons of extraterrestrial dust each and every year! Throw away your feather duster! You’re gonna need a backhoe and loader bucket!