Orbital smashups cause tiny pieces of space junk to emit signals that might be detected from Earth, a brand new study has found.
Space junk is a growing problem. As of November 2023, the world’s space surveillance networks were tracking about 35,610 pieces of space debris larger than 4 inches (10 centimeters), in accordance with the European Space Agency (ESA). That stuff is old satellites, used rocket stages and fragments spawned in orbital collisions and explosions.
These tracked objects are only the tip of the iceberg, nevertheless. About 1,000,000 fragments between 0.4 inches and 4 inches (1 to 10 centimeters) in size are believed to hurtle around Earth at enormous speeds. The estimated variety of fragments in orbit which might be smaller than 0.4 inches is 130 million, in accordance with ESA. These bits are mostly invisible to current debris-tracking methods, akin to ground-based radars and optical telescopes. Yet they pack enough power to destroy or seriously damage operating satellites in the event that they hit them.
A brand new method devised by researchers from the University of Michigan might help solve the issue.
Related: The rise of space tourism could affect Earth’s climate in unexpected ways, scientists worry
Using computer simulations, the researchers found that, when two objects collide at orbital speeds — enormous velocites that may approach 20,000 mph (30,000 kph) — they produce electrical bursts that will be spotted by Earth-based radio telescopes.
Space is large, so even with all of the clutter up there, things don’t collide that always. But when there’s a smashup, the tiny fragments that result are electrically charged. Each time two of those charged fragments approach one another, they offer off detectable sparks. The researchers compare this effect to the static electricity generated by rubbing certain kinds of materials against one another, like a balloon against your hair.
The researchers admit that these signals are short-lived and reasonably weak. Still, they think that with some extra work, the strategy could help track the so-far invisible, yet dangerous, tiny pieces of space debris that zoom around our planet.
“Immediately, we detect space debris by searching for objects that reflect light or radar signals,” Nilton Renno, a professor of climate, space sciences and aerospace engineering on the University of Michigan and the principal investigator behind the brand new mresearch, said in an announcement. “The smaller the objects get, the harder it becomes to get sunlight or radar signals strong enough to detect them from the bottom.”
The team’s modeling work suggests that the character of the signal emitted by the charged debris pieces is dependent upon the fabric the article is fabricated from and the speed at which the collision happens. The detection of weaker signals could also be obscured by the electrical noise generated by the detecting antennas. Along with that, signals which might be too weak may not find a way to go through Earth’s atmosphere. However the researchers think that the strategy could eventually detect debris pieces as small as 0.04 inches (1 mm).
The team plans to conduct further computer simulations and compare their results with real signals measured by NASA’s Deep Space Network, a worldwide network of antennas that helps the U.S. space agency communicate with its farflung space probes.
They hope the character of the signals could ultimately reveal quite a bit more in regards to the debris fragments than simply their position. The researchers think they may find a way to deduce a fraction’s shape and state from the measurements.
“We would like to know if an object is difficult or soft, because that can impact the way it orbits and the way damaging it might be,” Akhavan-Tafti said.
The rise in orbital debris is a giant concern for the space community. The amount of orbital debris is growing, but so is the variety of operational satellites. The percentages of devastating collisions are due to this fact getting ever higher. Researchers fear that just a few unlucky orbital smashes may lead to an out-of-control situation called the Kessler Syndrome. Predicted within the late Seventies by NASA physicist Donald Kessler, the syndrome is an unstoppable cascade of collisions wherein every latest crash produces fragments that threaten other spacecraft. The syndrome only stops when there are not any big objects left to be destroyed.
The study was presented at Second International Orbital Debris Conference in Sugar Land, Texas, on Tuesday (Dec. 5).