Drones are usually associated with the military; they're unmanned planes that often bring destruction on enemies from out of nowhere. But they can also be used for science.

A fleet of four surfboard-sized floating drones are motoring from California to Australia to study the ocean and set a record while they are at it).

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Called Wave Gliders, the drones — named Papa Mau, Benjamin, Fontaine Maru and Piccard Maru — provide scientific data on the ocean surface, which gets posted to the Internet for scientists to download and analyze free of charge.

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Eventually, the drones will be in the Guinness Book of Records for the longest sea voyage by unmanned vehicles. They were launched form San Francisco in November, and are currently separated by 40 to 50 miles. Moving at about 2.5 miles per hour, at the moment they are in the eastern Pacific, but when they get to Hawaii they will split up into groups of two. One pair will go to Sydney and the other to the Marianas Trench (they will cross the trench, but they won’t dive into it).

The drones are measuring salinity, water temperature, wave motion, weather, dissolved oxygen and fluorescence of the water. The instruments on the surface are solar-powered, so there’s no need to worry about batteries running out.

Each glider is equipped with instruments that dangle on a winged platform below, just a couple of feet below the surface (see image at right). As the glider moves, it's raised and lowered by the waves. The pilots can send a command every five minutes, adjusting course, changing which instruments are engaged and switching systems on or off.

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The drones were built by a California company called Liquid Robotics. Since 2009 Liquid Robotics has built 70 drones, and has sent one of its gliders across the Gulf of Mexico in the wake of the 2010 Deepwater Horizon oil spill. The company has also sold several to the National Oceanic and Atmospheric Administration.

There are a lot of advantages to drone systems like this. Francisco Chavez, senior scientist at the Monterey Bay Aquarium Research Institute, noted in an interview with Inside Science that the data scientists do have about the ocean is spotty in many places. The Wave Gliders will be a big help in filling some of those gaps.

Via Inside Science

Images: Liquid Robotics