CLOUD OF CLUTTER: A visualization of the population of tracked objects, primarily debris, in low Earth orbit. The objects are not scaled with respect to Earth. NASA
From Scientific American:
DARPA is soliciting pitches on how best to remove orbital debris.
Gazing up into the sky on a clear night, the heavens can appear as pristine as a mountain stream. But in truth, at least in Earth's vicinity, the trash factor in space may be more akin to what is found in New York City's East River. The region known as low Earth orbit (extending from 160 to 2,000 kilometers above Earth's surface), which is where many satellites spend their lives and "afterlives," has a litter problem caused by decades of neglect, and it's one that currently lacks an expedient solution.
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