The Expedition Begins

On the second day of their 15-day expedition to explore the ocean twilight zone aboard NOAA Ship Henry B. Bigelow, scientists from the Woods Hole Oceanographic Institution and National Marine Fisheries deployed Deep-See in the Atlantic Ocean. That first deployment was in relatively shallow water to test systems for a deeper deployment the next day, when the team headed to the edge of the continental shelf and planned dive to 1,200 meters.

During that deeper dive, 1,200-pound underwater sensor platform spent almost nine hours exploring the depths of the oceans twilight zone. The platform carries an array of sensors capable of detecting the vast amounts of living organisms that thrive in thick layers beneath the surface. Acoustic sensors and video cameras, including a holographic camera that can take pictures of extremely small animals functioned well and gave scientists on the ship a multi-faceted view of life in the twilight zone.

In addition to the high-tech eyes of Deep-See, the expedition team are using several other tools to explore life in the twilight zone. Among these are a simple trawl net used to bring up organisms for study—many of them largely undamaged in the collection process, thanks to a large box-like fitting at the end of the net known as a “coffin cod-end.” The other tool they are using is a MOCNESS (Multiple Opening/Closing Net and Environmental Sensing System), which is a much fancier version of a trawl net that allows scientists on the ship to open any of several different collection nets on command to collect animals from specific depths.

With two weeks left to go, the expedition is only beginning, and scientists aboard expect to make many new discoveries about this little-understood part of the ocean.