Space debris began to accumulate in Earth orbit with the launch of the first artificial satellite, Sputnik 1, into orbit in October, … See more

As of January 2019 there were estimated to be over 128 million pieces of debris smaller than 1 cm (0.39 in), and approximately 900,000 pieces between 1 and 10 cm. The count of large debris (defined as 10 cm across or la… See more

In 1958, the United States of America launched Vanguard I into a medium Earth orbit (MEO). As of October 2009 , it, the upper stage of Vanguard 1's launch rocket and associated piece of debris, are the oldest survi… See more

Space junk can be a hazard to active satellites and spacecraft. It has been suggested that Earth orbit could even become impassable if the risk of collision becomes too great.
However, s… See more

Radar and optical detectors such as lidar are the main tools for tracking space debris. Although objects under 10 cm (4 in) have reduced orbital stability, debris as small as 1 cm can be tracked, however determining orbits to all… See more

An average of about one tracked object per day has been dropping out of orbit for the past 50 years, averaging almost three objects per day at solar maximum (due to the heating and expansion of the Earth's atmospher… See more