Beyond the Stars: Space-Cleaning Robots and the Vast Potential of Space Robotics

In June 2023, Astroscale, a space robotics company, released a new video showcasing the capabilities of its End of Life Services by Astroscale-Multiple (ELSA-M) robotic spacecraft in the satellite deorbiting process. This process first involves a visual inspection of a client satellite, followed by alignment and docking maneuvers. Using its thrusters, the ESLA-M then lowers the client satellite's orbit toward an atmospheric trajectory until it safely disintegrates during reentry into the Earth's atmosphere. Once the client satellite is committed to a destructive trajectory, the ESLA-M would then detach itself from the client satellite and further adjust its own orbit to prepare for its next mission.

Astroscale also launched its Generation 2 Docking Plate, designed for long in-orbit operations. This plate facilitates easy grabbing of satellites in need of de-orbiting, promoting responsible use of Earth's orbital resources.

The use of robots in space is far from a recent development. For decades, these mechanical workers have been integral in deep space missions, offering numerous advantages, such as enabling precise and reliable operation, and the ability to operate in harsh environments, which improves mission cost-effectiveness and efficiency, while reducing risk to human life. Throughout the years, robots have played key roles in satellite deployment and maintenance, space debris removal, space mining, and space station operations, among other use cases.

Robots Tackling the Space Debris

Space junk, also known as space debris, refers to non-functional, human-made objects orbiting the Earth. This debris consists of defunct satellites, spent rocket stages, fragments from satellite collisions, and other discarded components from space missions. As of 2022, the European Space Agency (ESA) reports that there are approximately 36,500 large (>10 Centimeter (cm) in diameter) objects, 1 million medium-sized (1 cm to 10 cm), and a staggering 130 million small (1 Millimeter (mm) to 1 cm) space debris pieces in orbit.

Space debris creates potential risks and threats, such as increasing collision risks between space craft, damage to satellites, the Kessler Syndrome, and the chain reaction of space debris, creating potentially unusable regions of orbit due to pollution, economic impact, threat to space infrastructure, space exploration risks, and many others. With increasing space exploration and satellite launches, the amount of space debris has grown significantly, and it has become a pressing concern for space agencies and satellite operators. HDI Global Specialty's 2023 Technical Study: Space Debris reveals a surge in satellite deployments, particularly due to “mega” constellations like Starlink and OneWeb. These constellations may double or triple operational satellites within 5 years, resulting in a more crowded space. As a consequence, the likelihood of collisions increases, leading to a cascade effect of debris generation and further collision risks. Consequently, the space debris monitoring and removal sector is rapidly expanding to address the urgent need to mitigate space debris risks and to preserve space sustainability. In the space debris monitoring and removal marketplace, several companies have been working on innovative solutions, such as capturing and deorbiting debris, or pushing it to burn up in the Earth's atmosphere. The objective is to reduce the risks posed by space junk to operational satellites and to ensure a sustainable space environment for continued space activities.

In the space debris domain, robots have been used extensively. Tokyo-based Astroscale has been one of the key pioneers in the space debris removal business. Founded in 2013, Astroscale has developed innovative and scalable solutions across the spectrum of in-orbit servicing, including life extension, in situ space situational awareness, end of life, and active debris removal to create sustainable space systems, and to mitigate the growing and hazardous buildup of debris in space. ClearSpace, a Swiss startup, spin-off of the EPFL Space Center (eSpace), is another name to look out for in the space debris business. The company develops technologies to remove unresponsive or derelict satellites from Low Earth Orbit (LEO). ClearSpace One, the company’s small satellite solution, finds, captures, and removes man-made space debris. In 2022, ClearSpace and Astroscale were awarded ~US$5.18 (£4) million from the UK Space Agency to design missions to remove existing pieces of space debris. Once the satellite mission designs have been completed, the teams, along with other U.K. space companies, could receive further funding to see the United Kingdom’s first national space debris removal mission with a projected launch in 2026.

Besides Astroscale and ClearSpace, Rogue Space Systems, an American space startup, is also one of the more interesting companies in the space debris marketplace. Rogue has been developing Orbital Robots (Orbots) for in-space maintenance and services to satellites. The Orbots fleet will be supported by the AI-Enabled Sensory Observation Platform (AESOP), which would position the Orbots near the target satellite and make decisions automatically to ensure the target satellite can be serviced safely. Orbots would offer inspection, maintenance, repair, and transport services to satellites in LEO, Medium Earth Orbit (MEO), and Geostationary Orbit (GEO). Rogue has delivered its first payload and completed preliminary design reviews for two Orbots.

The once far-fetched idea of robots in deep space has now evolved into a tangible reality. Space robots, once confined to the pages of comic books and Science Fiction (sci-fi) movies, are now playing a pivotal role in space. With space robotics technology forging new frontiers, the potential for space robotics is ever-expanding, and these mechanical workers look set to play a crucial role in the cosmos.

ABI Research shares a positive outlook on space robotics, and these are some of the interesting prospects to anticipate in this field:

• Space Debris: Maintaining our orbits is essential to the future of the space economy. Clearing space debris not only guarantees the safety of operational satellites and future missions, but also opens promising business prospects. As concerns about space debris increase, technologies that support the removal of space debris would most certainly be a key part of the future space economy, so “Taking Out the Space Trash” would be a lucrative and essential venture for the space industry.
• Space Tug: Space tugs, also known as space tugboats, are unmanned spacecraft designed to maneuver and relocate objects in orbit. An example would be moving a spacecraft from LEO to a higher-energy orbit like a geostationary transfer orbit, a lunar transfer, or an escape trajectory. Space tugs aim to offer a range of in-orbit applications in a compact, reusable form to ensure the safety and accessibility of space. Like aquatic tugboats assisting ships in need of maneuvering or supply restock, space tugs aid in-orbit spacecraft with difficult situations, such as fuel depletion, blockage by debris, or malfunctions. As the space tugs operate without astronauts, such space missions are cost-effective, efficient, and mitigate risks. Modern space tugs have also been engineered for functions like reducing space junk, retrieving satellites from orbit, refueling spacecraft, extending satellite life spans, and other essential functions for enhancing space operations. With an increasing number of satellites and space infrastructure in orbit, the demand for space tug services is likely to rise, creating lucrative opportunities for companies in this sector to provide essential and cost-effective solutions for space missions and operations.
• Asteroid Mining: Asteroid mining is the concept of extracting valuable resources, such as metals, minerals, and water, from asteroids. These celestial bodies are rich in rare elements and precious metals, making them potential sources for raw materials essential for space missions and Earth's industries. The process involves identifying suitable asteroids, capturing them, and then extracting and processing the resources on-site or transporting them back to Earth or other locations in space. Advancements in robotics technology might enable scientists to drill asteroids for precious metals, such as iron, nickel, and platinum. The development of asteroid mining technology comes with a huge price tag, but it may be a worthwhile endeavor as the asteroids offer access to extremely valuable resources that may be rare here on Earth. For example, Asterank, which measures the potential value of over 6,000 National Aeronautics and Space Administration (NASA)-tracked asteroids, has found that mining the top 10 most cost-effective asteroids (closest to Earth and highest in value) could generate a profit of US$1.5 trillion. One asteroid, the 16 Psyche, has been reported to contain an estimated US$700 quintillion worth of gold, enough for each person on Earth to receive about US$93 billion. However, the asteroid mining field is still in its early stages, and significant technological, economic, and regulatory challenges need to be overcome before asteroid mining becomes a viable commercial reality.
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