Should We Be Worried About Space Trash?

The largest garbage dump in the world is not the Apex Regional Landfill or the Great Pacific Garbage Patch. It’s actually so high up in the sky that it’s invisible to the human eye. One hundred to 1,000 miles above Earth’s surface is a region of space called the low Earth orbit. This area is the perfect destination for space stations, satellites, and telescopes—and, unfortunately, for their trash. When spacecraft are retired, they are either programmed to fall back to Earth or turned off and left floating in orbit. The low Earth orbit has now become a junkyard where millions of pieces of space debris float around billions of dollars of active satellites. This debris can be as large as a discarded part of a rocket or as small as a chip of paint. Unlike your typical garbage dump, space junk isn’t just sitting in a heap—it’s moving. Very fast. Propelled by Earth’s orbit, space debris can reach speeds of up to 18,000 miles per hour. Moving at such high speeds, space junk can be destructive. Even a piece of debris as small as a grain of sand can damage space shuttle windows and force astronauts to make risky replacements. Over the past fifty years, an average of one piece of space debris has fallen to Earth’s surface every day. Most debris burns up as it falls back to Earth, which creates metallic ash that can disrupt the atmosphere. Many of the pieces that make it to the ground are large enough to do some serious damage. In 1978 NASA suggested that the buildup of space junk in our orbit would cause a chain reaction—the more debris there is floating around, the more likely collisions are to happen, which creates even more debris, which creates more collisions… You get the picture. This buildup of space junk could eventually make the low Earth orbit—home to satellites that power technology like GPS and the Internet—unusable. There aren’t any legal regulations on space trash, and scientists are unable to fully catalogue our interstellar pollution. One estimate from NASA is that there’s more than 9,000 tons of space debris in low Earth orbit. That’s the weight of 60 blue whales. In 2010 only a thousand satellites orbited our planet; 15 years later the number is closer to 10,000. So... Keep one eye on the sky! Be careful out there—and don’t forget to recycle.