Statement on the comments from Secretary of War Pete Hegseth

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Inside their cleanroom, the team is busy building more modules for future Artemis missions. Each one takes about 18 months to put together but has taken thousands of engineering hours to design. Everything on board has to work perfectly.

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Leonardo da Vinci is usually credited with conducting the first systematic study of friction in the late 15th century, a subfield now known as tribology that deals with the dynamics of interacting surfaces in relative motion. Da Vinci's notebooks depict how he pulled rows of blocks using weights and pulleys, an approach that is still used in frictional studies today, as well as examining the friction produced in screw threads, wheels, and axles. The authors of this latest paper used an experimental setup similar to da Vinci's.

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