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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.
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.