# The Peril of Human-Made Space Debris on Our Cosmic Aspirations
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Chapter 1: Humanity's Cosmic Aspirations
Since ancient times, humanity has gazed upon the heavens, pondering what exists beyond our world. Ancient civilizations, including the Mayans and Egyptians, revered celestial bodies, intertwining them with their beliefs and cultures. Our fascination with the cosmos has persisted, inspiring countless writers, scientists, and dreamers to imagine a future where we explore the Sun, moon, and distant planets, seeking out extraterrestrial life and unraveling the mysteries of the universe.
The dream of space travel is both thrilling and daunting. Ironically, the very advancements that propel us into space may soon become obstacles to further exploration. Each rocket launch and satellite deployment adds to the perilous space debris that encircles our planet, creating a trap that grows more dangerous each year. The cost and complexity of accessing space are already significant, and if this debris problem escalates, it could severely hinder our space endeavors for decades, if not longer.
Section 1.1: The Challenges of Reaching Space
To officially reach space, a vehicle must ascend to 100 km (≈ 62 mi) above Earth's surface. As altitude increases, the atmosphere thins, posing a challenge for space travel. At 11 km (≈ 7 mi), 77.5% of the atmosphere has been traversed, and by 31 km (≈ 19 mi), only 1% remains. This thinning atmosphere requires substantial energy to overcome air resistance.
Gravity also complicates the journey. Even at 1,000 km (≈ 621 mi), an object weighing 10 kg (≈ 22 lbs) retains a significant portion of its mass. Rockets must achieve incredible speeds to escape Earth's gravitational grasp—28,000 km/h (≈ 17,400 mph) to reach the International Space Station at 360 km (≈ 224 mi) and a staggering 40,000 km/h (≈ 25,000 mph) to travel to the moon or beyond.
Upon launch, rockets ascend rapidly to leave the atmosphere and then tilt to orbit the planet, entering a Low Earth orbit where they can remain for extended periods. The cost of launching payloads varies, with NASA spending an average of $23,750 per kilogram (≈ 2.2 lbs) compared to SpaceX's lower rate of about $6,078 per kilogram.
Section 1.2: The Dangers of Space Debris
As we have launched rockets into space for decades, the remnants—spent boosters, defunct satellites, and debris—have accumulated in Low Earth orbit, creating a hazardous environment. Currently, there are approximately 2,600 non-functional satellites and around 10,000 larger objects, with countless smaller fragments adding to the clutter. These pieces of debris travel at speeds of up to 30,000 km/h (≈ 18,000 mph), posing a grave threat to operational satellites.
Even a tiny fragment, like one the size of a pea, can inflict catastrophic damage upon impact. For instance, astronaut Tim Peake shared an image of a small chip that was gouged from the International Space Station's Cupola window due to a collision with space debris. The European Space Agency noted that this damage could have originated from a minuscule paint flake.
Through decades of space exploration, we have inadvertently created a perilous junkyard in orbit. This debris endangers our multi-trillion-dollar global infrastructure, which is essential for communication, navigation, weather observation, and scientific research. If one of our 1,957 active satellites were to be struck by a piece of debris, it could be irrevocably destroyed.
As Ben Greene, head of Australia's Space Environment Research Centre, pointed out, the problem of space junk is worsening. We currently lose several satellites each year to collisions, and predictions suggest that we may be just a few years away from a potential crisis where the majority of our satellites could be lost.
Chapter 2: The Path to a Clean Orbit
While the situation appears dire, there may still be opportunities to mitigate the threat posed by space debris. The space industry is becoming more adept at avoiding collisions, and reusable rockets like SpaceX's Falcon 9 are reducing the generation of new debris. However, the rapid expansion of the space sector and sporadic weapon tests continue to complicate cleanup efforts.
One innovative approach involves capture and retrieval missions. For instance, the RemoveDEBRIS satellite successfully ensnared a simulated piece of junk using a net in September 2018. If the debris is too large for a net, a harpoon could be employed, utilizing a sail to create drag and facilitate orbital decay.
Other futuristic solutions include employing giant electromagnets to manipulate satellites without direct contact, thus minimizing the risk of further fragmentation. Additionally, lasers could be utilized to vaporize smaller debris or alter their trajectories to safer orbits.
The potential use of an ion beam shepherd (IBS) is being explored by researchers in Japan and Australia, aiming to develop a non-contact method for debris removal. As Kazunori Takahashi from Tohoku University stated, effective debris removal techniques will be crucial for the future of space activities.
Ultimately, the urgency of addressing the space debris issue cannot be overstated. Without swift action, our cosmic aspirations could be extinguished before they even begin, relegating our dreams of interstellar colonization to mere fantasies.