Speaker
Description
This presentation covers the first results of a study on the atmospheric effects of re-entering satellites in the mesosphere (40 – 100 km). Currently, the disposal method of choice for most LEO satellites is an atmospheric re-entry. However, in recent years a number of concerns have been raised about the amount of man-made material projected to burn up in the Earth’s atmosphere in the coming decades as well as the chemical products created during the burn-up and their impact on the atmosphere and our planet’s climate. It is present believe that there are three main emissions from re-entering satellite components which potentially can alter ozone concentrations and the radiative budget in the middle atmosphere, namely: black carbon (aerosols), aluminium alloys, and thermal nitric oxide (NO).
OHB and IAP Kühlungsborn took the initiative to investigate the potentially harmful substances produced during re-entry of space objects, their influence on the atmosphere and methods to models and detect them. In particular it was considered that the number of re-entering satellites will increase dramatically in the near future. This is driven by trends for mega constellations and cheaper access to space. Two aspects were studied and will be presented at the workshop: Based on the Chemistry-Transport Model at the Leibniz Institute of Atmospheric Physics (CTM-IAP) the effects of thermal NO on ozone in the upper stratosphere-mesosphere-mesopause region were computed. In addition, the impact of the increased mass of black carbon and aluminium on the radiative balance of the middle atmosphere has been discussed.
Initial results show no criticalities. NOx-driven ozone depletion on the middle atmosphere by re-entering satellite components show only negligible effects even with larger projected total masses re-entering. However, the picture is not complete. The presentation will conclude with an overview of the open questions and next steps as well as an appeal to collaborate on this important question and share outcomes as they become available.
