<P> Space debris (also known as space junk, space waste, space trash, space litter or space garbage) is a term for the mass of defunct, artificially created objects in space, most notably in Earth orbit, such as old satellites and spent rocket stages . It includes the fragments from their disintegration, erosion and collisions . As of December 2016, five satellite collisions have resulted in generating space waste . </P> <P> As of 5 July 2016, the United States Strategic Command tracked a total of 17,852 artificial objects in orbit above the Earth, including 1,419 operational satellites . However, these are just objects large enough to be tracked . As of July 2013, more than 170 million debris smaller than 1 cm (0.4 in), about 670,000 debris 1--10 cm, and around 29,000 larger debris were estimated to be in orbit . Collisions with debris have become a hazard to spacecraft; they cause damage akin to sandblasting, especially to solar panels and optics like telescopes or star trackers that cannot be covered with a ballistic Whipple shield (unless it is transparent). </P>

What's the name for a chunk of space debris that is still floating in space