Sunrise prep
UW-APL engineer Paul Aguilar up at sunrise to prep the Axial Base Horizontal Electrometer Pressure-Inverted Echosounder (HPIES), a novel OOI instrument measuring horizontal electrical field, pressure & acoustic travel time from seafloor to sea surface.
![](https://www2.whoi.edu/site/ooi-expedition/wp-content/uploads/sites/143/2022/08/RCA-SUNRISE-FbSA75OWYAIUcGQ-1024x683.jpeg)
Credit: NSF-OOI/UW/CSSF/V22.