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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A faint outer bubble, made mostly of hydrogen, marks an earlier period of material sloughed off. Closer to the center, a more complex cloud of mixed gases forms the "brain" inside the shell. Webb's instruments also show more dust glowing in mid-infrared light, while the near-infrared view lets background stars and even distant galaxies shine through.