During a seven-day expedition on the E/V Nautilus in August 2021, OTZ team members tested the capabilities of the autonomous underwater vehicle Mesobot and broadcast its work to the world using live video streams.

The vehicle, which was designed to study the ocean twilight zone, carried with it two major instruments. The first, a highly-sensitive radiometer, is designed to measure the light penetration through the ocean depths—a physical factor that plays a vital role in the lives of the animals that call this region home. The radiometer also allows Mesobot to control its mission by following an "isolume", or depth layer receiving an equal amount of light, just like a mesopelagic fish might.

The second instrument, a cluster of 32 pumps and filters, helped the team collect environmental DNA (eDNA) from the water. These devices collect trace amounts of DNA left behind by animals recently in the area and can help scientists understand species that live in the twilight zone — even if they never see them. In this video, climb aboard the E/V Nautilus, and learn more about how researchers are studying the zone using these high-tech tools.