ESA
The particle is just a speck compared to the 10-foot-long satellite (and its two 33-foot-long solar wings), but it was hurtling through space so fast (about 25,000 miles per hour) that the shock wave from the impact tore a 16-inch-hole into the satellite.
The Sentinel-1A satellite is a radar imaging satellite used to detect, map, and track changes in the environment.
Although the impact of the particle caused a slight power loss as well as tiny changes in the orientation and orbit of the satellite, it hasn't affected the satellite's routine operations. That's because the satellite already generates more than enough power to operate, and this power reduction is pretty small in comparison.
After noticing the slight loss of power, the ESA analyzed the satellite's status and activated its onboard cameras, which were only installed to monitor the deployment of the solar rings after the satellite's launch in 2014.
Through these cameras they were able to get pictures of the array, which revealed the damage to one of the solar wings.
The ESA is still analyzing whether the particle was a natural speck of space rock or a small piece of human-made space debris, though Holger Krag, Head of the Space Debris Office at ESA, told Motherboard that a human-made particle seems likelier.
According to the ESA, these types of hits are not entirely unexpected. Even though scientists can keep an eye on larger meteoroids and pieces of space debris, particles like this are too small to be on their radar.
"These very small objects are not trackable from the ground, because only objects greater than about [2 inches] can usually be tracked and, thus, avoided by maneuvering the satellites," Krag said in a press release.
Litter in space
Space trash, or debris, consists of defunct spacecrafts and satellites, abandoned rocket stages, and fragments created from erosion, disintegration, and collisions. NASA is currently tracking more than 500,000 pieces of debris that are the size of a marble or larger, orbiting Earth.
And according to NASA, space is swarming with millions of pieces of debris, like this particular space particle, that are too small to be tracked.
At the moment, space agencies have no way of eliminating any existing space junk from orbit. They can only shield their spacecrafts from the objects and work to find ways to generate less space debris in the future.
One way to do this, Motherboard reports, is by redirecting bigger hunks of space trash away to prevent them from colliding and breaking apart into smaller pieces. That's one important way, Krag told Victoria Turk, that we can "keep space fit" for future missions.