NASA scientists continue to develop and upgrade orbital debris models to describe and characterize the current and future debris environment. Engineering models, such as ORDEM 3.1, can be used for debris impact risk assessments for spacecraft and satellites, including the International Space Station. Whereas, evolutionary models, such as LEGEND, are designed to predict the future debris environment. They are reliable tools to study how the future debris environment reacts to various mitigation practices.
Credit: NASA ODPO
Before the launch of Sputnik 1 in 1957, there were no manmade objects in Earth orbit. But the number of satellites has steadily increased. All of the objects in the video are tracked by the U.S. Combined Space Operations Center’s Space Surveillance Network. The objects travel in different directions, at different altitudes, on different elliptical planes. Although this image makes low Earth orbit look more congested than it is, the congestion worsens each year.