Underwater robots and submersibles exploring the ocean floor use special pressure-compensated lubricants that must work at depths where water pressure can exceed 1,000 atmospheres—enough to crush an empty soda can instantly. These oils need to mix with seawater intentionally through special bladders that equalize pressure, preventing seals from being crushed, while also resisting the corrosive effects of salt that would rust ordinary machinery within days. Deep-sea lubricants must stay fluid in near-freezing water temperatures of 2°C at the ocean bottom, yet also handle the heat generated by motors and hydraulics working against enormous resistance. Scientists studying hydrothermal vents or searching for shipwrecks depend on these specialized oils lasting through missions that can extend for months without the possibility of maintenance or refills.