A new study conducted by researchers at the University of Malaga (UMA) reveals a dark side to space exploration and satellite technology. Space debris, or space junk, is a threat to space exploration and also our planet.
The escalating quantity of defunct objects in space is a direct result of human activities beyond Earth’s atmosphere. The mess we have made in space could be setting us up for a potentially devastating future.
Since the launch of the first satellite in 1957, the proliferation of space debris has been relentless. The European Space Agency (ESA) estimates that there are now over 131 million pieces of space junk. These range in size from one millimeter to ten centimeters, circumnavigating our planet at speeds of 36,000 kilometers per hour.
Remnants of rockets, dysfunctional satellites, and even stray astronaut tools make up the clutter. The debris presents a serious threat to operational satellites and future space missions. “Any piece larger than one centimeter is potentially lethal in case of collision,” said Professor José Luis Torres.
Together with Professor Anelí Bongers, Torres led a project focused on Space Economy, which applied quantitative analysis to establish a theoretical model that outlines an optimal rate of satellite launches based on the existing amount of space debris.
Using data from NASA and ESA, the model uses computational simulations to investigate the impact of anti-satellite tests on the volume of space debris and the consequential probability of collisions with operational satellites. There are approximately 6,000 satellites that are currently orbiting Earth.
The UMA researchers dynamically calculated the quantity of space debris based on the optimal behavior of space-operating companies in determining the rate of satellite launches and the number of satellites. Their study shows that the amount of space debris adversely influences the quantity of launches and satellites.
“The calculations also show that anti-satellite tests generate more than 102,000 new pieces of this waste larger than one centimeter and that its negative effects take 1,000 years to disappear due to the high altitude at which tests are carried out,” said the researchers.
The experts approached the study of space debris from an economic perspective. They view outer space as a global common good that, similar to the high seas, risks overexploitation.
This approach highlights the lack of express regulation beyond a non-binding United Nations International Treaty. As a consequence, they identify a clear “market failure,” where the absence of property rights encourages misuse of this resource, resulting in negative externalities.
The researchers express concern that our increasing dependence on tech companies operating in space implies a continued rise in the volume of space debris. With that comes an increased probability of collision. “We are facing a huge unregulated market, which problems have just started,” they wrote.
In a startling scenario, the UMA study also investigates the fallout of a hypothetical space war. The simulation assumed the destruction of 250 satellites. Under such circumstances, the model predicts a surge of space debris by an astonishing 25.5 million fragments,each larger than one centimeter. This would exponentially escalate the probability of collision and satellite destruction.
The study, published in the journal Defense and Peace Economics, is a stern reminder of the potential consequences of space debris on our global economy and the physical problems it may impose on Earth.
The research also highlights the implications for human activities in space, both commercial and scientific. If we don’t check the current rate of space debris generation, it could render space exploration impossible.
Space debris, also known as space junk, refers to objects that are no longer functional and orbit the Earth. These objects include defunct satellites, spent rocket stages, fragments from collisions, and other remnants of human activities in space. The accumulation of space debris poses a significant threat to operational satellites, spacecraft, and even astronauts.
Space junk can originate from various sources, such as satellite launches, on-orbit explosions, and mission-related activities. Collisions between objects in space generate more debris, creating a cascade effect known as the Kessler Syndrome.
Space debris can vary in size, from tiny paint flecks and screws to larger objects like dead satellites. Even smaller debris particles can pose a risk due to their high velocities in orbit.
Space junk can be found in different orbital regions, including low Earth orbit (LEO) below 2,000 km, medium Earth orbit (MEO) between 2,000 km and 35,786 km, and geostationary orbit (GEO) at 35,786 km. The majority of debris is concentrated in LEO.
Space debris poses risks to operational satellites, as even a small collision with debris can cause significant damage or complete destruction. This risk increases with the growing number of satellites in orbit. It also poses a threat to crewed missions and the International Space Station (ISS).
Space agencies and organizations track and monitor space debris using radar systems, telescopes, and other technologies. They catalog and predict the trajectories of larger objects to minimize the risk of collisions.
To address the problem, several mitigation measures have been proposed and implemented. These include designing satellites and rockets with measures to limit debris generation, deorbiting satellites at the end of their operational life, and removing larger debris through active removal missions.
Space debris is a global issue that requires international cooperation. Organizations like NASA, ESA, and other space agencies collaborate to develop guidelines, share tracking data, and work on debris mitigation strategies.
Efforts are underway to develop advanced technologies for cleaning up space debris and prevent further accumulation. These include concepts like active debris removal, space-based lasers, and other innovative solutions. The goal is to ensure the long-term sustainability of space activities and preserve the space environment for future generations.