9 Unsolved Ocean Mysteries
Lost submarines of 1968
The year 1968 saw the still-unexplained loss of submarines by four countries: the United States, Russia, Israel, and France. Some say the losses could have been government cover-ups or (at least in the U.S. case) the nuclear-tipped torpedoes misfiring into the vessel.
Two-thirds of marine species remain unknown
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Wow, that’s a lot of unknown creatures.