How much did SpaceX's Starship Flight 7 explosion pollute the atmosphere?

SpaceX Starship explosion may have released 45.5 tons of pollutants, raising atmospheric concerns.

: SpaceX's Starship Flight 7 exploded, dispersing metal fragments across the Caribbean. The rocket's upper stage exploded at 90 miles high, releasing a significant 45.5 metric tons of metal oxides and 40 metric tons of nitrogen oxides into Earth's atmosphere. Connor Barker from University College London provided these preliminary figures, highlighting concerns about potential ozone layer damage. The use of stainless steel instead of aluminum in the upper stage reduces some environmental dangers.

In mid-January, SpaceX's Starship Flight 7 experienced a rapid unscheduled disassembly, commonly known as an explosion, scattering hot metal fragments over the Caribbean. Jonathan McDowell, an astronomer and space debris specialist, reported that the upper stage disintegrated at an altitude of about 90 miles and weighed approximately 85 tons without its propellant. Atmospheric chemistry researcher Connor Barker from University College London estimated the debris's impact, suggesting the mishap released 45.5 metric tons of metal oxides and 40 metric tons of nitrogen oxides into the atmosphere.

Barker emphasized that these are preliminary numbers and cautioned about the harm such emissions could inflict on the Earth's ozone layer. Nitrogen oxides are particularly notorious for their potential to deplete ozone. However, due to the Starship's stainless steel composition—as opposed to aluminum used in many other rockets—the threat level might be diminished as the burning of aluminum produces alumina, a substance known for impacting the ozone negatively.

There remains uncertainty about the full extent of pollution resulting from the explosion. Notably, airborne metallic pollutants from the mishap could be equivalent to a third of annual meteorite burnouts. Given the increased frequency of atmospheric re-entries, there are growing scientific concerns about long-term air pollution and potential impacts on climate change, as pollutants might linger longer due to high elevation dispersion.