H2O (Hawaii-2 Observatory) H2O (Hawaii-2 Observatory) ? In 1998, scientists used the remotely operated vehicles (ROV) Jason and Medea to create the pioneering long-term seafloor observatory called H2O (Hawaii-2 Observatory). They spliced an abandoned submarine telephone cable into a termination frame. The frame relays power and communications to a junction box, which serves as an electrical outlet for scientific instruments. Illustration by Jayne Doucette.
