by Jeff Foust — October 13, 2020
WASHINGTON — While launch providers are doing a better job at disposing of upper stages left behind in orbit, rocket bodies still constitute the most dangerous pieces of orbital debris.
The European Space Agency released Oct. 12 its annual Space Environment Report, the agency’s assessment of orbital debris. The report identifies more than 25,000 tracked objects, including satellites, upper stages and debris.
While collisions between objects can create additional debris, a bigger concern is the breakup of satellites or rocket bodies caused when batteries or propellant tanks on them explode. “The biggest contributor to the current space debris problem is explosions in orbit, caused by leftover energy — fuel and batteries — onboard spacecraft and rockets,” Holger Krag, head of ESA’s Space Safety Program, said in a statement. “Despite measures being in place for years to prevent this, we see no decline in the number of such events.”
Rocket bodies are of particular concern because their size can create a large number of objects. A breakup of a Japanese H-2A upper stage in 2019 created more than 70 pieces of tracked debris, one of which came close enough to the International Space Station in September to warrant a maneuver by the station.