The “Knocking on Wood” Wikipedia page mentions Roud’s conclusion, and this claim of a 19th century origin has circulated online as the final say on the matter. If you go back to the original, though, Roud’s proposal actually ends on an ambivalent note: “Before this theory [of 19th century origins] can be finally accepted, however, an examination of the history of European forms of this custom would be advisable.”
Launching Artemis III, IV and V before the end of 2028 will not be easy, and Isaacman said it is essential that NASA rebuild its workforce and regain the technical competence to support a higher launch cadence, moving from one flight every 18 months or so to a flight every year. That pace, he argued, will reduce risk.
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