Space exploration is exciting and many of us tune in to launch broadcasts. Since space exploration became commercial, rocket launches are frequent. But have you thought about the amount of ‘stuff’ left behind orbiting Earth? Some of the stuff is deliberately put into orbit, like the International Space Station and communications satellites. As of mid-2024, there are over 10,000 active satellites orbiting Earth, with a significant portion belonging to SpaceX’s Starlink constellation.
This marks a substantial increase from previous years, driven largely by the rapid deployment of satellite networks like Starlink. The total number of satellites, including inactive ones, reached 11,330 by mid-2023. The growth in satellite numbers reflects advancements in space technology and increased demand for global internet connectivity
According to Google, satellites in orbit serve several key purposes:
• Communications: About 63% of satellites are used for communications, including television, radio, internet, and military applications.
• Earth Observation: Approximately 22.1% of satellites monitor environmental conditions, weather, and provide geographical mapping
• Navigation: Satellites like GPS provide precise location and timing information for navigation on land, sea, and air
• Technology Development: Around 7.8% of satellites are used for technology development and demonstrations
As if satellites were not enough, the space around Earth is full of debris, made worse by collisions between the ‘stuff’, breaking it into smaller pieces. The danger of these pieces was starkly illustrated by the film
Gravity starring Sandra Bullock and George Clooney: Dr. Ryan Stone (Sandra Bullock) is a brilliant medical engineer on her first shuttle mission, with veteran astronaut Matt Kowalski (George Clooney) in command of his last flight before retiring. But on a seemingly routine spacewalk, disaster strikes. The shuttle is destroyed, leaving Stone and Kowalsky completely alone – tethered to nothing but each other and spiraling out into the blackness.
According to the search app Perplexity: The increasing number of satellites significantly impacts space debris, creating several challenges:
• Crowded Orbits: More satellites lead to crowded orbits, increasing the risk of collisions, which can generate additional debris
• Kessler Syndrome: As collisions occur, they can trigger a chain reaction, known as the Kessler Syndrome, where debris creates more collisions, potentially making orbits unusable
• Collision Risks: Millions of debris pieces, even small ones, pose collision risks to active satellites, threatening critical infrastructure
• Debris Management: Current technology for debris removal is limited, necessitating international cooperation and regulation to manage space debris effectively
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To reduce space debris, several measures can be implemented:
• Design Improvements: Satellites should be designed to minimize debris release, such as using tethered components instead of ejecting them
• End-of-Life Planning: Satellites should be deorbited or moved to a graveyard orbit after their mission ends
• Active Debris Removal: Technologies like ground-based lasers and space tugs can nudge debris out of orbit
• International Policies: Global guidelines and cooperation are essential to enforce debris mitigation practices
• Innovative Technologies: AI and digital twins can enhance collision avoidance and debris tracking
Cleaning up small space debris presents several challenges:
• Detection and Tracking: Small debris, often less than 10 cm, is difficult to detect and track due to its size and high velocity. Current tracking systems are not fully effective for these smaller objects
• Cost and Technology: Developing and deploying technologies for debris removal is expensive and technically challenging. Many proposed solutions, like lasers or space tugs, are still in experimental stages and require significant investment. The cost of removing small space debris is generally higher compared to large debris
• International Coordination: Space debris management lacks comprehensive international regulations, making coordinated clean-up efforts difficult
So, before we worry about aliens, we need to navigate the space around Earth.
Ann Marie Thomas is the author of five medieval history books, a surprisingly cheerful poetry collection about her 2010 stroke, and the science fiction series Flight of the Kestrel, Intruders, Alien Secrets & Crisis of Conscience and Planet Downfall are out now Follow her at http://eepurl.com/bbOsyz
