Dr. John Barentine FRAS on Nostr: nprofile1q…aez5z Micrometeoroids are mostly made up of carbonaceous, siliceous or ...

nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqkvymhf67ewyj9qsscj793a0je4vxfx0hjv8z39d05cvgpktyt7us2aez5z (nprofile…ez5z) Micrometeoroids are mostly made up of carbonaceous, siliceous or iron-rich material. Spacecraft, on the other hand, are mostly made of aluminum, iron and titanium with traces of other metals (Li, Al, Cu, Nb, Ag, Hf, Pb). And re-entering spacecraft are estimated (https://www.pnas.org/doi/10.1073/pnas.2313374120) to now contribute about ten times as much aluminum that ablates in the upper atmosphere compared to micrometeoroids.