NEEMO 16 aquanauts <a href="https://en.wikipedia.org/wiki/Steve_Squyres" class="extiw" title="en:Steve Squyres">Steve Squyres</a> (top bunk, Cornell University) and <a href="https://en.wikipedia.org/wiki/Kimiya_Yui" class="extiw" title="en:Kimiya Yui">Kimiya Yui</a> (bottom bunk, JAXA astronaut) in the Aquarius underwater habitat during decompression at the end of the NEEMO 16 undersea exploration mission.  NASA photo in public domain.
NASA
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