Metals from spacecraft reentry in the stratosphere

Measurements of aerosol particles in the stratosphere show that metals that were vaporized during the reentry of rocket boosters and satellites accumulate in the stratosphere. These metals are incorporated into natural sulfuric acid particles in the stratosphere. With the rapidly increasing number of spacecraft reentry events, in the coming decades a majority of sulfuric acid particles in the stratosphere could contain novel metals from spacecraft in addition to the meteoric metals that are already present.

Over 20 elements from reentry were detected in stratospheric particles. We are able to quantify the relative amounts of a number of these metals, including lithium, aluminum, copper, and lead. For the EGU meeting we will also present results on several more metals such as titanium, niobium, molybdenum, silver, and tin. These atmospheric measurements can be compared to inventories of the elemental composition of spacecraft.

These metal-containing particles are found in the same air that contains the ozone layer. The addition of materials from spacecraft might affect heterogeneous chemistry in the ozone layer or change ice nucleation in polar stratospheric clouds.