Space industrialization
Résumé
Humans are messy, and not just here on Earth (Bohannon, 2015). On November 15, 2021, a Russian anti-satellite test produced more than 1,500 pieces of orbital debris that threatened the crew of the international space station. The crew members sheltered in capsules in case they had to evacuate. So far, more than 8000 tons of orbital debris have been generated from human space missions. Moreover, the dawn of ‘space tourism’, a term popularized by recent space missions, marks an acceleration of the era of space
industrialization. While recent reports have focused on space collisions induced by space debris, there is actually little discussion on the effect of space industrialization on the earth's environment. Here, we review the impacts of space debris on earth's environment. About 23,000 objects larger than a softball, more than about 10 cm, amounting to a total weight of 8000 tons, are actually orbiting the earth at speeds up to 17,500 miles per hour. By reflecting and scattering sunlight, man-made space objects and debris have increased the night sky brightness on earth by approximately 10% of the luminance of a typical natural
night sky. Upon burning, some space debris consumes ozone and release carbon dioxide, which may—unlike in the lower atmosphere—induce cooling and contraction of the thermosphere due to increased heat shedding via infrared radiation. Rocket and plane propellants are likely to pollute the earth’s atmosphere and deplete the stratospheric
ozone. The falloff of nuclear powered engines and parts may cause large radioactive pollution. As a consequence, mitigation guidelines for orbital debris have been proposed by some countries, though with limited success to date.