The missing Titanic submersible that was lost in the North Atlantic on Sunday was believed to have less than two days of oxygen remaining on board as of Tuesday night, as ships and aircraft raced to search an area larger than Connecticut. The submersible, the Titan, has five passengers on board — its maximum capacity — and it is a tight squeeze. Promotional materials showed an interior with no seats, only a flat floor passengers could sit on, and a single view port 21 inches in diameter. Here’s a look at the missing sub and the vessels searching for it. #titanic #titansubmarine