March 12, 2014
Over the past 15 years, we’ve been sprinkling space with eensy satellites. Universities, startups and national space programs have all launched fit-in-your-hand satellites that, variously, study life in space, flash Morse code and snap smartphone photos. This Sunday, a Cornell University-based team hopes to launch 104 poker chip-sized circuit boards that will orbit Earth on their own:
Small satellites are cheap to build and deploy, so they save space programs money. They’re also affordable and simple enough for students to build, so they’re great educational tools. But their popularity made Popular Science wonder… The Earth is already surrounded by space junk. Isn’t launching 100-plus nanosatellites a bit like throwing crumbs on the living room floor?
Luckily, many satellites are able to do something crumbs aren’t. They clean themselves up. Small satellites launched into orbit 650 kilometers or less above the surface of the Earth soon fall back down toward Earth. They plunge through the Earth’s atmosphere and, because they’re small, they burn up before reaching the ground. In addition, few spacecraft orbit below 650 kilometers in altitude, so there’s not as much for small satellites to hit.