Another cloud of Russian space debris has bloomed in orbit.
An object in orbit around the Earth cataloged as 32398 broke up on April 15, the 18th Space Defense Squadron of the US Space Force. tweeted tuesday (May 3). Sixteen pieces of space debris associated with the event are currently being tracked, the squadron added.
Object #32398 was an ullage engine from a space tug that helped orbit three Russian GLONASS satellites in 2007, according to journalist and author Anatoly Zak, which runs RussianSpaceWeb.com. (GLONASS is the Russian version of the GPS navigation system.)
Related: Kessler Syndrome and the Space Debris Problem
According to astrophysicist and satellite tracker Jonathan McDowell, based at the Harvard-Smithsonian Center for Astrophysics, these GLONASS spacecraft lifted off atop a Russian Proton rocket, whose upper stage had two small vacuum engines. The ullage engines slightly boost their parent rocket stages, to ensure booster fuel is properly positioned in the reservoirs for on-orbit engine restarts, McDowell explained in a series of tweets tuesday. (You can’t rely on gravity to pull the thruster to the engine, after all.)
These Proton upper stage vacuum engines are known as SOZ engines, and there are currently 64 of them in Earth orbit, McDowell tweeted. The acronym is short for “Sistema Obespecheniya Zapuska,” which roughly translates to “Launch Assurance System,” he said.
“SOZ engines don’t use all of their propellant when firing. And they have a tendency to explode years or decades later, leaving a pile of debris in a very elliptical orbit. At least 54 SOZ engines now have exploded.” McDowell tweeted.
The SOZ engine that just exploded had traveled the Earth in a very elliptical path, approaching up to 241 miles (388 kilometers) and up to 11,852 miles (19,074 km), McDowell said in another tweetnoting that “debris will take some time to re-enter”.
“So – this debris event was predictable and is well understood; still very unfortunate,” he wrote.
Space waste is a growing problem for satellite operators and mission planners. the European Space Agency (ESA) estimates that about 36,500 pieces of debris at least 4 inches (10 centimeters) wide are currently swirling around the Earth. And Earth’s orbit is likely home to around 1 million objects between 0.4 inches and 4 inches (1 to 10 cm) in diameter, according to the ESA.
Russia added to the debris population with a widely condemned anti-satellite test (ASAT) in November 2021. The nation destroyed one of its own defunct satellites with a missile, spawning a new debris field in the same orbital vicinity as the International Space Station (ISS). ISS operators had to perform engine burns to dodge debris from the Russian ASAT.
Mike Wall is the author of “The low(Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for extraterrestrial life. Follow him on Twitter @michaeldwall. Follow us on twitter @Spacedotcom Or on Facebook.