Japanese Startup Evaluates Space Debris Defense Using Ground-Based Fusion Laser
The Japanese startup EX-Fusion intends to test a ground-based fusion laser system to “capture, remove, or push out” objects functioning in Earth’s orbit, a move that might completely redefine space safety.
EX-Fusion stated in a statement that they intend to deploy ground-based laser systems to address the rising issue of space debris, which is a major concern for international space agencies and satellite operators. The announcement also marked the beginning of a relationship with the Australian company EOS Space Systems.
According to a news release from EX-Fusion, “the amount of space debris around the Earth has increased significantly in recent years, leading to catastrophic collisions with valuable space assets essential to life on Earth, such as telecommunications, finance, location, and navigation.” “Using optical ground stations with high-power laser systems to remove or redirect space debris and prevent these catastrophic collisions is one effective strategy for mitigating the space debris problem.”
Space debris, which includes spent rocket parts, crashed satellite fragments, and retired satellites, is a serious threat to crewed space missions, operating satellites, and the International Space Station.
Currently, the U.S. military tracks objects in orbit larger than 10 cm, but smaller, more difficult-to-detect bits are becoming a greater hazard. According to estimations from the European Space Agency (ESA), there are currently around 175 million space debris particles, with sizes ranging from 1 mm to 1 cm, floating around Earth’s orbit.
As to the European Space Agency (ESA), a spacecraft might be rendered inoperable or the International Space Station’s protective shields could be breached by a collision with a 1 centimeter piece of space debris. A normal satellite would experience “catastrophic fragmentation” upon impact from an item that is 10 cm or greater.
The need to address the issue of space debris, including enforcement against space litterbugs, has grown as the number of space-related activities increases globally.
The U.S. Federal Communications Commission (FCC) fined Dish Network $150,000 in October 2023 for improperly deorbiting its EchoStar-7 satellite. This was the first time an enforcement action had been taken against a firm for its role in the expanding space debris issue.
It is not a new idea to employ lasers to combat space junk. NASA stated in October 2023 that it will be working with West Virginia University (WVU) to create a system of space lasers that will protect spacecraft from deadly collisions with space debris.
“Our goal is to develop a network of reconfigurable space-based lasers, along with a suite of algorithms,” Hang Woon Lee, the director of the Space Systems Operations Research Laboratory at WVU, explained in a press release. “Those algorithms will be the enabling technology that makes such a network possible and (to) maximize its benefits.”
Unlike previous satellite-based laser solutions, however, EX-Fusion intends to use its laser technological know-how to target space trash from the ground up.
Nikkei Asia, a Japanese news site, reports that EX-Fusion plans to test its technology by deploying a powerful fusion laser at the observatory outside Canberra, Australia, which is run by EOS Space Systems.
The initiative will be split into two stages, the first of which will track debris less than 10 cm, according to Nikkei. In the next stage, the strength of a ground-based laser will be increased in order to safely incinerate the debris after it has been decelerated and removed into Earth’s atmosphere.
The project partner of EX-Fusion, EOS Space equipment, has functional equipment for tracking space debris orbiting Earth by optical means and laser ranging. The company’s defense portfolio includes a high-energy laser (HEL) weapon system from EOS.
The EOS HEL can take “swift and decisive action” against unmanned aerial systems (UAS), according to the company’s website. According to a product document, the laser weapon has a range of up to 2.5 miles, which is sufficient to fight drone threats.
The strategic importance of having a ground-based “satellite killer” is growing as geopolitical tensions over space use increase; such a weapon might be a vital part of a country’s military arsenal.
However, James Bennett, the executive vice president of EOS Space, stated during a visit to Japan in November that the powerful lasers EX-Fusion will be employing to clear space debris are quite different from the weapon-grade lasers utilized in military applications.
The method developed by EX-Fusion applies pulsed energy to flying debris using diode-pumped solid-state (DPSS) lasers, which act as brakes to slow down and remove the fragments.
The company’s original, audacious plan was to “build and power” the first laser fusion nuclear reactor in history using its DPSS laser technology.
According to EX-Fusion’s website, the process of laser fusion involves directing a strong laser beam onto a pellet of hydrogen fuel that is several millimeters in size. This creates a high-pressure “implosion,” which sets off a nuclear fusion reaction.
“The power of a laser for destroying space junk is an order of magnitude lower than for nuclear fusion, but they share technical challenges such as controlling them via special mirrors,” said Kazuki Matsuo, CEO of EX-Fusion, in an interview with Nikkei.
At the 2018 International Workshop of Space Debris, EOS Space Systems has earlier put out the concept of remotely manipulating space debris via a similar ground-based photon pressure device.
It is a difficult challenge to successfully remove space junk using ground-based fusion lasers.
Accurate tracking and targeting technologies are necessary when pointing spacecraft at small, fast-moving targets from Earth’s surface. Another major problem is atmospheric interference, where changes in atmospheric density can deflect and weaken laser beams, decreasing their efficacy.
Another important consideration will be the laser’s power. The beam needs to be adjusted to prevent collateral damage to neighboring operating satellites while still being powerful enough to strike the debris.
Finally, to guarantee that the debris, once struck, safely re-enters the Earth’s atmosphere without endangering other space assets, the timing and position of the laser firing must be precisely planned.
It will take a combination of cutting-edge technology and clever engineering solutions to address these issues.
Notwithstanding these difficulties, EX-Fusion sees them as a fantastic chance to show off the laser fusion technology’s economic feasibility.