The space is getting crowded – humans have put more than 20,000 satellites in orbit since the beginning of the space age, and there are plans to launch thousands of others in the coming years. Some of these satellites have already burned in the atmosphere or fell back on Earth, usually in the ocean, but more than 13,000 are still there. About a fifth is inactive, simply orbiting as space waste.
In the last two decades, hundreds of these satellites have collided to create millions of pieces of shrapnel. This creates a constant risk of collision for active satellites and the international space station – such a serious problem that various surveillance networks around the world are closely observed thousands of larger objects to move out of the way when necessary.
The growing threat of spatial debris requires greater orbit maneuverability and a reduction in the amount of garbage. British startup Magdrive states that it can help with both, through a new spaceship propulsion system that will be launched into space for the first time at the end of this year and will be fed by solid metal.
“We wanted to build something that really moved the needle to humanity in the space industry and letting us climb the stairs to become a space civilization,” says Mark Stokes, a magdrive co -founder in 2019.
He states that using a solid metal propulsion system can make satellites 10 times more maneuverable, while reducing mass dedicated to propulsion by 10 times.
Magdrive is working on three versions of its space thrusters and, as they work with solid metal, can one day until it is fed by spatial waste collected directly into orbit, turning it a threat into a fuel source.
The best of both worlds
Satellites need propulsion systems for a number of reasons, including changing to a different orbit, compensating for the atmospheric drag that would destabilize the orbit they are, avoid debris and eventually leave the orbit.
THE Most satellite propulsion systems are currently chemical or electrical But according to Stokes, both have disadvantages: “The chemical propulsion has a very high thrust, but its efficiency – or its miles per gallon, if you prefer – is very low.”
“On the other hand, electric propulsion systems today have completely opposite characteristics. They have a very low thrust, but excellent efficiency, excellent miles per gallon.”
Humanity’s greatest ambitions for the space economy, including asteroid mining, major satellite constellations and orbit spaceplace construction are, says stakes, out of reach for now because these propulsion systems require an exchange between power and efficiency – a decision that needs to be made even before the satellite is launched.
“We are building the first system of this type that has the best of both worlds. It is electric propulsion, but has an improvement of magnitude in the thrust, with a reduction in magnitude in volume and mass,” he added.
The first version of the Magdrive System – called Warlock – is scheduled to be launched in orbit in June 2025. It works by creating energy using onboard solar panels, as well as current electric propulsion systems. But while current electrical systems use energy to ionize, or detonate, a pressurized gas – usually a toxic chemical called hydrazine – the magdrive uses it to ionize solid metal.
Metal is very dense, which means it occupies less space on board than a pressurized gas tank. This, he adds, would make life easier for satellite manufacturers, who consider the pressurized tanks “a headache” as they are difficult to work and can cause broken explosions, while metal is inert and has no degrading over time.
For now, the magdrive uses copper, chosen because it is relatively cheap and widely available, although any metal does the work, according to stokes. Once detonated, the metal is transformed into extremely hot and dense plasma, or electrically charged gas.
“What you get is this highly energetic copper plasma coming out of the back of the propeller,” continues Stokes, which moves the propeller in the opposite direction.
Fueled by garbage?
For now, the system is not refuelable. In the farthest future, however, Stokes believes that the system could get your existing space waste fuel collecting dead metal satellites to use as a propeller – although so far this plan is only hypothetical.
“The benefit of this is that we will be able to close the new space era cycle using resources that are already there,” says Stokes.
This would make Magdrive, adds Stokes, the only propulsion system that doesn’t have to take your fuel every time.
“Now, each satellite needs to bring its thruster from the earth, and that’s like building a new train every time you get out of the season,” he says.
The company is aiming for its first commercial implementation next year, and aiming customers with a wide range of needs: “We are building a standardized hardware piece that can fit aboard any satellite – so virtually anyone throughout the space industry,” explains Stokes.
“This includes a variety of different applications, from land observation to satellites and communications maintenance,” he says, and can be used in satellites weighing from 10 pounds to 400 pounds.
Significant challenges
According to Minkwan Kim, an associate professor of astronautics at the University of Southampton, UK, who was involved in research and collaborations with Magdrive, using solid metal fuel offers simplified storage and handling compared to gas or liquid propellants.
It allows a simple design that is particularly suitable for mass production, creating a viable path for future megaconstels that require large -scale satellites.
“However, the use of metal propellant has a significant challenge: surface contamination, particularly for solar panels and optical systems,” he adds.
Because metallic plasma is produced during operation, it can easily deposit on surfaces, potentially affecting the overall performance of the spacecraft. Stokes says that in the magdrive system, metallic fuel is consumed completely during the reaction, but then recombines in what he calls “scattered inert material,” which he says only a small risk of contaminating nearby surfaces due to particle output speed – “nothing to be overwhelmed to reach other components or satellites.”
Ensuring a reliable and consistent thrust generation, Kim adds, represents another challenge, particularly for precise maneuvers.
The heating and cooling cycles through which metallic fuel passes during thrust generation can alter its atomic crystal structure, affecting its performance as a propeller. To maintain uniform thrust output, a precise monitoring and control system would be necessary, adding complexity to the system.
Regarding the use of spatial debris such as fuel, Kim says it is theoretically possible, but there are significant technical and regulatory challenges.
The first is that although space waste may seem a free resource, the UN outer space (OST) treaty states that ownership of objects launched into space remains unchanged, even if they become debris. This means that the permission of the original owner is required before recycling a satellite.
In addition, some satellites contain confidential data or proprietary technology, making owners reluctant to give access. Finally, the launch country is responsible for any incidents caused by a recycled satellite, adding another layer of legal complexity.
Then there are practical issues, says Kim: “Disabled satellites are uncontrollable and often fall, making recovery extremely difficult. Capturing and protecting them requires complex maneuvers, a technology still in their childhood,” he says.
Kim added that these satellites are not only made of metal, but also from materials such as silicon and polymers, which is a problem because the quality and purity of the metallic thruster directly impact thrust performance, so without rigid control over the composition of the collected metal, it would be difficult to obtain a reliable and predictable thrust.
“As a result, although the metal derived from space waste may be suitable for non -precision maneuvers, such as disabled, it is unlikely to be viable for high precision propulsion.”
Orbit of the land is full of space waste and this is a problem
Was this content originally published in solid metal -powered satellites use spatial waste as fuel? on the CNN Brazil website.
Source: CNN Brasil
Charles Grill is a tech-savvy writer with over 3 years of experience in the field. He writes on a variety of technology-related topics and has a strong focus on the latest advancements in the industry. He is connected with several online news websites and is currently contributing to a technology-focused platform.
