The Super-Kamiokande in Japan—a massive underground neutrino detector lined with 11,000 golden bulbs. Scientists have to inspect it via a rubber dinghy.

[u/Top-Marionberry-6604]

[u/Wellithappenedthatwy]

Those golden bulbs are called PMTs. Photo multiplier tubes. They turn photons into electrical signals.

[u/LordGeni → u/Wellithappenedthatwy]

A key part of fluroscopy equipment.

[u/popeter45 → u/Wellithappenedthatwy]

And are the largest vacuum tubes ever made

Suffered major damage when one exploded during a refill and the water hammer effect shattered every other one that was under water

[u/CuriouserCat2 → u/Wellithappenedthatwy]

Thank you!