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Massive explosion rocks SpaceX Texas facility, Starship engine in flames
(interestingengineering.com)
This is a most excellent place for technology news and articles.
Ok. Boo.
https://www.pbs.org/newshour/show/how-a-new-space-race-could-be-harming-the-earths-atmosphere
https://www.space.com/rocket-exhaust-pollution-upper-atmosphere
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EF002612
Sooty exhaust from RP-1 and aluminum oxide particulates from discarded upper stages will not be a problem with Starship.
Starship uses methalox, and the upper stage is designed to be reusable.
And the lower stages?
Also reusable, like Falcon 9.