Scientists have identified what could potentially be the “deepest known blue hole” in the world, extending so far down that the bottom has not yet been reached. Researchers described how the underwater abyss’s extensive depths could harbor a “biodiversity to be explored” in a recent study published in the journal Frontiers in Marine Science. Indeed, new measurements taken during a December scuba-diving expedition indicate that the Taam Ja’ Blue Hole (TJBH), located in Chetumal Bay off the Yucatan Peninsula, extends at least 1,380 feet (420 meters) below sea level — nearly the height of Trump Tower in Chicago. That’s 480...