Humanity has set its sights on the stars for its future and envisions a new place for itself among the heavens. However, throughout history, human exploration has had disastrous consequences for the native environments encountered. At first glance, space exploration has decided there is no environment to ruin or indigenous peoples to displace. It seems, nothing much can go wrong. From the emptiness of space to the barren deserts of Mars, space appears hardened to potential ruin. Unfortunately, we have already begun to precipitate environmental disasters in space.
In the Earth’s orbit,there are thousands of satellites, tens of thousands of pieces of tracked debris, and staggering amounts of untraceable debris. Orbital decay is the main mechanism for removing orbital debris, wherein an object’s orbit is gradually reduced by external forces such as drag, tidal interactions, or radiation pressure. However, every year more debris is added than is removed. Eventually, the number of objects in orbit could reach a critical mass and cause a Kessler Cascade. At this critical level of debris, objects collide and split into more debris; The resulting increase in debris increases the likelihood of collisions, and leads to more debris being created. Even manoeuvrable objects such as satellites or stations would be at risk. This profusion of debris in or adjacent to useful orbits could eventually greatly reduce our ability to deploy and operate spacecraft, jeopardising the immense benefits of space utilisation.
Even before reaching critical mass, this debris causes issues and makes operations in Low Earth Orbit (LEO) increasingly difficult. Micro-debris sandblasting satellites reduce solar panel efficiency and damage sensitive parts.Larger debris requires costly evasive manoeuvres if they can be spotted, and may render satellites inoperative if they collide. Low Earth Orbit is currently the main area of human activity in space and has been so for decades. The looming disaster is no surprise, however. The concept of a Kessler cascade was first theorised in 1978, over four decades ago, when our utilisation of LEO was much less valuable than today.
Regulators are pushing for proper management and disposal of satellites to mitigate the proliferation of orbital debris and there are attempts to remove orbital debris. As more nations and companies achieve launch capability, the patchwork of nationalised mitigation efforts will cover a lower percentage of launches and be less and less effective. International efforts must be made to confront this possibility.
Today, humanity has set sight on further targets. The Moon is the next major destination for many governments, both as a launch site into deeper space and a hub for industry. Human efforts on the moon are limited to areas with water deposits, mainly found in the polar regions. These areas could be jeopardised by contamination with dangerous fuels, damage from hazardous landings, and national competition. Speculated future explorations involve terraforming Venus, settling on the moons of Jupiter, and Space X’s efforts towards Mars. All these visions for the future exhibit a total lack of environmental awareness. Terraforming by nuking Mars or stripping off Venus’s atmosphere has incredible impact and lacks consideration of its side effects or long-term viability. Any large presence on other worlds will contaminate them and potentially disrupt ecosystems, jeopardising the discovery of life beyond earth. There is fundamental value to finding extraterrestrial life beyond avoiding any potential harm it could cause. These schemes would require a level of coordination and effort sustained across a timespan never seen before. Hopefully, they would encounter greater scrutiny as they approached realisation.
The impact of humanity’s expanding presence in space will be huge, and bring a multitude of benefits to Earth. The Apollo program reaped many rewards, and our expansion into LEO touches every aspect of life. Even the fight to preserve Earth’s own climate relies on humanity’s presence in orbit. All of these benefits are at risk, however, as we continue to threaten the environments of space. Action must be taken to prevent environmental collapses. International efforts must be made to mitigate damage done, to repair what can be repaired, and to establish legal frameworks for responsible endeavours in space. Military actions, which are some of the most damaging, must be heavily limited. Private companies, often culprits for the least transparent and most damaging terrestrial environmental disasters, must be globally regulated to prevent this being carried to the stars. Fundamentally, whilst all these practical measures would help, a change to the philosophy of space exploration is needed. Missions must be planned with their impacts in mind and the future of the environment and humans considered. This concept is not new; the early days of space exploration were characterised by optimistic and benevolent language about the future. The outer space treaty, written sixty years ago, wrote a noble sentiment into the preamble of the treaty: “Recognizing the common interest of all mankind in the progress of the exploration and use of outer space for peaceful purposes”. Sadly, humanity has not lived up to its own expectations. As more nations reach launch capability these hollow words have rung false. Many nations and companies exploit space with as little consideration as possible, and we will pay the price for this. If humanity is to fully enjoy the benefits of our endeavours, we must return to a kinder philosophy of space exploration.