It was Jan. 11, 2007 when China launched a ballistic missile at its defunct weather satellite, Fengyun 1C, setting off an explosion that marked the largest manmade creation of space debris in the history of space exploration. The destruction sent more than 3,000 pieces of trackable debris and an estimated 150,000 debris particles encircling the Earth.
China’s antisatellite missile test wasn’t the first of its kind. The United States had conducted a similar test in 1985, when it used an antisatellite missile to destroy its Solwind P78-1 satellite at 555 kilometers altitude. Nevertheless, China’s destruction of Fengyun 1-C occurred at about 850 kilometers altitude, well above the Earth’s atmosphere, ensuring that most of the fragments would remain in orbit for decades.
While historic, the Fengyun event is just one conspicuous feature of an increasingly complex international problem, one with no easy solution. The space debris population has grown in size since the earliest days of spaceflight, when the U.S. Naval Research Laboratory's (NRL's) Minimum Trackable Satellite (Minitrack) receivers began tracking the first manmade objects to go into orbit—Russia’s Sputnik in 1957, then NRL’s own Vanguard satellite in 1958.
Today, the operational community is tracking more than 20,000 objects larger than 10 centimeters in the official satellite catalog, while the estimated population of objects between one and 10 centimeters in diameter runs to 500,000, according to NASA’s Orbital Debris Program Office. Though the probability of a collision between a spacecraft and debris today remains incredibly low, such a collision with an object as small as a paint fleck has the potential to disrupt or even end a space mission.
The rate of collisions also has the potential to increase exponentially, according to retired NASA scientist Donald J. Kessler, who founded the Orbital Debris program office. In 1978, he proposed a theory now known as the " Kessler Syndrome" that debris generated by a collision could cause even more collisions, leading to a runaway cascade of collisions that would create a massive debris field in low Earth orbit, posing a real threat to the future of space operations. The catastrophic consequences of such a series of events were dramatically illustrated in the 2013 movie Gravity.
At NRL, aerospace engineers, astrodynamicists, research physicists, and others are working in concert with the Air Force, NASA, and other partners to approach the problem in a number of ways, beginning with NRL’s Mathematics and Orbit Dynamics Section. There, researchers are collaborating with government partners and the private sector to track orbital debris while preparing for the completion of a new “space fence” that will radically transform our view of orbital debris from Earth.
Meanwhile, engineers with NRL’s Geospace Science and Technology Branch are developing a space-based optical instrument that can detect orbital debris. At the Blossom Point satellite tracking facility in Maryland, NRL’s high-precision, orbit-determination software is contributing to reliable “lights out” operations that ensure spacecraft can maneuver in orbit safely.
All of this work represents a continuation of NRL’s long tradition of research and development for space operations, which extends back to the creation of the Minitrack system and the launch of the Vanguard satellite, today the oldest manmade object in space.
To view a NASA video that shows a simulation of the debris from the destruction of the Fengyun 1-C satellite, which was destroyed on Jan. 11, 2007, see here. The explosion created more than 3,000 pieces of trackable debris and an estimated 150,000 debris particles. It was the largest manmade creation of space debris ever recorded.
Also see “The Big Data of Space Debris”