He was in Washington recently to pick up two awards — the Navy Distinguished Public Service Medal and the Hubbard Award from National Geographic, the Society's highest honor given for distinction in exploration, discovery and research.

No human has returned to the deepest part of the ocean, although remotely operated vehicles have.

Walsh applauds those advances in technology, but laments that most of the world's deep oceans remain unexplored and that only a handful of vessels — manned or unmanned — exist to do the job.