In February, a 20-year-old military weather satellite experienced an extreme temperature spike and exploded in orbit. The leftover debris – from what was once the U.S. Defense Meteorological Satellite Program (DMSP) F13 – could potentially pose a threat to other spacecraft in orbit.
The European Space Agency first used ground-based radar to detect the debris that the DMSP-F13 explosion left in orbit. At the time, the agency believed the debris wouldn't be a problem for other spacecraft and missions.
Now, a team of scientists from the Astronautics Research Group at the University of Southampton have further investigated the debris produced by the explosion — finding pieces that hadn't been detected by radar. They created a new technique called Cloud Evolution in Low Orbits (CiELO), which allowed them to render a map pinpointing the debris and other spacecraft, such as U.S. and Russian satellites in sun-synchronous or polar orbits.
"The fragments from the explosion spread around the Earth forming a band, which can be crossed by spacecraft with orbits that are quite different from the one of DMSP-F13," said PhD student Francesca Letizia.
In addition to the larger debris already detected, the researchers found 100 additional pieces, along with 50,000 smaller fragments from the DMSP-F13 explosion. They also determined that even the tiniest pieces could easily collide with spacecraft on missions in Earth's orbit, possibly causing great damage.
"Even though many of these objects will be no bigger than the ball in a ballpoint pen, they can disable a spacecraft in a collision because of their enormous speed," said Dr. Hugh Lewis.
"In the case of the DMSP-F13 explosion, our work has shown that the introduction of a new cloud of small-sized debris into orbit will have increased the risks for other spacecraft in the vicinity, even if the risk from the larger fragments has been discounted."
The amount of space debris in Earth's orbit has grown steadily over the past few decades, as more countries launch spacecraft and satellites into space. Scientists believe that Earth's orbit has nearly 3,000 tons of space junk — mostly composed from the remains of old satellites, rockets and old spacecraft wreckage.
Space debris has become such a concern for space agencies that NASA researchers want to attach a laser cannon to the International Space Station to begin blasting some of that debris away.
Photo Credit: University of Southampton