In 1901, steamer ship City of Rio de Janeiro sank on its way into the San Francisco Bay, killing 128 passengers and disappearing into the ocean. The famous lost ship stayed disappeared for over 100 years, its location suspected but never confirmed. Now, thanks to a sonar technology called "Echoscope", scientists have pinpointed the wreck's location, and created a 3D map of the briny remains.
An archeological expedition led by the Office of National Marine Sanctuaries Maritime Heritage Program this past November used an Echoscope and a remote vehicle to trawl the bottom of the ocean. When they finally discovered the ship around 287 feet below the surface, there wasn't much left. Just "a crumpled, scarcely recognisable iron hulk encased in more than a century worth of mud and sediment," according to the agency's report. But the sonar technology and 3D images it produced illuminated for researchers how the City of Rio sank; the way the ship is positioned indicates that it went down too quickly for most passengers to escape.
In the course of the City of Rio investigation the team found and mapped other wrecks, including the City of Chester, which sank in 1888 after colliding with another ship.
The Echoscope was developed by a company called CodaOctopus, and the real-time 3D imaging machine is one of the most powerful sonar tools around.
It's not just used for shipwreck hunting and mapping: Lockheed Martin uses it for subsea inspections on oil and gas operations. It helps demystify the ocean floor... whether that's a long-lost shipwreck or, someday, the lost city of Atlantis. [NOAA via Wired]
Picture: Gary Fabian/NOAA