The Jian Seng

Some ghost ships are so mysterious, they barely even have a backstory. In 2006, an Australian Coastwatch plane found a ship floating 180 km south-west of Weipa, Queensland in the Gulf of Carpentaria. It had a broken tow rope, so being lost while dragged around the water would explain why it was empty.
But that was about all investigators could go on. The name Jian Seng was printed on the side, but there was nothing else to identify the ship. Investigations found no records of distress signals, no identifying documents or belongings, and no reports of a missing boat. They couldn’t even figure out who it belonged to or where it came from. The most they can figure out is that it probably supplied food and fuel to fishing boats, but that didn’t answer why no one tried to save it when it broke off.
The Mary Celeste

On November 7, 1872, a captain, his wife, and two-year-old daughter, and seven crewmen set out from New York to Italy aboard the Mary Celeste. A month later, they should have arrived, but the British ship Dei Gratia caught sight of the boat drifting in the Atlantic. The crew went onto the Mary Celeste to help anyone onboard but found it completely empty.
Six months’ worth of food and the crew’s belongings were still there, but its lifeboat was gone. The ship’s floor was covered in three feet of water, but that was far from flooded or beyond repair. It’s become one of the world’s most famous ghost ships—thanks largely to the fact that Sir Arthur Conan Doyle used the boat as inspiration for his short story, “J. Habakuk Jephson’s Statement”—with theories from pirates to mutiny to murder.
The most likely explanation is that the captain didn’t know the extent of the damage and ordered the crew to abandon ship at the first sight of land, but the world will never know for sure.
The Carroll A. Deering

The Carroll A. Deering cargo ship and its ten-man crew successfully made it to Rio de Janeiro in 1920, despite needing to change captains when its original one fell ill, but something strange happened on its way back to Virginia. A lightship keeper in North Carolina said a crewman who didn’t seem very officer-like reported the ship had lost its anchors while the rest of the crew was “milling about” suspiciously.
Another ship spotted the Carroll A. Deering near Outer Banks the next day in an area that would have been a strange course for a ship on its way to Norfolk, Virginia. The following day, a shipwreck was spotted, but dangerous conditions kept investigators away for four days. When they went aboard, they found food laid out as if they were getting ready for a meal, but the crew’s personal belongings and the lifeboats were gone.
The US government followed leads on pirates, mutinies, and more, but they all came up fruitless.
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