Speaker
Description
The surge in space travel, especially due to the implementation of satellite mega-constellations for global internet requires mitigation strategies to counteract the increasing problem of orbital space debris. The common strategy for low Earth orbit (LEO) objects is to ensure their reentry into Earth’s atmosphere, where they ablate and burn up in the atmosphere. Due to the ever increasing launch mass into LEO, this raises the question of the significance of this anthropogenic injection compared to natural, meteoric sources, which provide a constant flow of cosmic dust and larger meteoroids into Earth’s atmosphere. A comparison of the two sources shows, that already in 2019 the anthropogenic mass input has been significant (2.8%) compared to the natural input. This number will only rise in the future due to the ongoing implementation of satellite mega-constellations. More than 5000 satellites are in orbit right now with more than 100000 proposed satellites. Considering a worst-case scenario, the injection of metals could increase to up to 90%, aerosol injection up to 94%. As the material is mainly injected into mesosphere heights, possible influences on mesospheric and even stratospheric chemistry, with effects on the ozone layer, cloud formation or the climate are thinkable. Therefore, further study and precautions are necessary, in order to protect our atmosphere from yet another human-made influence.
