We know more about the dark side of the moon than we know about the bottom of the deep blue sea. But scientists are finally beginning to get a glimpse into this murky abyss and, to their surprise, they see -- light! In this hour of To the Best of Our Knowledge, photosynthesis on the ocean floor, a "vampire squid from hell," and one man's search for shipwrecks.

SEGMENT 1

Russell Seitz tells Steve Paulson about the experiments which seed the ocean with iron in an effort to influence the planet's climate and curb global warming. Seitz thinks the idea is worth considering although this kind of eco-engineering worries many of his colleagues. Seitz is an affiliate of the Olin Institute for Strategic Studies at Harvard.

SEGMENT 2

Joe Cann teaches earth sciences at the University of Leeds in England. He tells Steve Paulson about the light produced as a result of a chemical process around the hydrothermal vents in the deep ocean. He says this is where photosynthesis, and all of life, got its start. Also, marine illustrator and master sea story spinner Richard Ellis tells Jim Fleming about some of the bizarre creatures who live in the deep ocean, and his own fascination with the mysterious giant squid. Ellis is the author of a number of books on marine life including "Deep Atlantic: Life, Death and Exploration in the Abyss."

SEGMENT 3:

Best-selling novelist Clive Cussler hunts shipwrecks in his spare time. He talks about it in his book "The Sea Hunters: True Adventures with Famous Shipwrecks," and in this conversation with Jim Fleming. Also, historian Steven Biel tells Judith Strasser why we seem to be obsessed with the sinking of the Titanic. Biel is the author of "Down with the Old Canoe: A Cultural History of the Titanic Disaster."

Distribution dates:

• week of 12/01/96 - hour 2
• week of 06/22/97 - hour 2