Russian rocket stage explosion creates debris swarm in space
26 October 2012
After an August launch failure, a Russian Briz-M rocket stage with loaded fuel tanks exploded in low Earth orbit on October 16, creating a debris storm. NASA and other space agencies say the debris could threaten the International Space Station, as well as hundreds of satellites.
Briz-M rocket upper stage
The upper stage was launched on a Proton rocket on August 6, with a mission to place Indonesia's Telkom 3 and Russia's Express MD2 communications satellites into geostationary orbit 22,000 miles above Earth's equator.
But the Briz-M failed at the start of the third of four planned engine burns, leaving the vehicle and its payloads well short of their targeted altitude. At the time of the mishap, the stage still had more than half of its hydrazine and nitrogen tetroxide propellants in its primary and auxiliary fuel tanks.
The substances are hypergolic, meaning they combust when coming in contact with each other. With the amount of propellants left on-board, any contact would have generated an explosion.
Around 500 fragments from the rocket stage are now thought to be in orbit.
This breakup marks the third explosion since 2007 of a Briz-M stage left with partially-full propellant tanks after a launch failure, according to Spaceflight Now. NASA's orbital debris program office says each of the previous Briz-M explosions in 2007 and 2010 produced about 100 pieces of debris.
Another Briz-M upper stage from a launch failure in August 2011 is still intact in orbit and has not ruptured yet.
The breakup was mentioned in a daily International Space Station status report posted Tuesday on a NASA website. The debris cloud is "believed not to be insignificant," officials wrote in the daily update.
The 450-ton ISS can change its orbit, when necessary, to avoid individual pieces of space debris. These manoeuvres have become more common since 2008 after a Chinese anti-satellite test and the high-speed crash of two satellites collectively sent approximately 5,000 chunks of space junk into the paths of spacecraft in low Earth orbit.
The August 6 failure occurred on a mission managed by Khrunichev, the Russian builder of the Proton rocket and Briz-M upper stage. Investigators found fault with a component of the stage’s pressurisation system.