Mars may be sneezing out dust into the solar system that’s visible from Earth

If you go outside at night in a dark spot with no moonlight, you may spot a faint glow in the sky that follows the zodiac constellations. This glow is called the zodiacal (zo-DIE-uh-cull) light, and is caused by tiny particles of dust orbiting the Sun outside Earth’s orbit. They faintly reflect sunlight back to us, generally barely visible by eye though obvious enough in photos.

What’s not obvious is the source of that dust. It was once thought to be from asteroids; big rocks in the main astero...