TIL. Thank you!

but the piece that truly brought him to international attention was Threnody to the Victims of Hiroshima (see threnody and atomic bombing of Hiroshima), written in 1960 for 52 string instruments. In it, he makes use of extended instrumental techniques (for example, playing behind the bridge, bowing on the tailpiece).

https://en.wikipedia.org/wiki/Krzysztof_Penderecki

Threnody to the Victims of Health Insurance Companies.

It's hard to tell. It looks deep like a cello, but the bridge doesn't look quite high enough. Maybe at the tardigrade scale stringed instruments are made a little differently.