The Seaglider is a deep-diving Autonomous Underwater Vehicle (AUV) designed for missions lasting many months and covering thousands of miles.
[6][7] Seaglider measures temperature, salinity and other quantities in the ocean, sending back data using global satellite telemetry.
Seaglider UUVs are in use worldwide, collecting oceanic physical properties and performing various other missions for oceanographers, including the U.S. Navy, government agencies and research organizations.
Seaglider "flies" through the water with extremely modest energy requirements using changes in buoyancy for thrust coupled with a stable low-drag hydrodynamic shape.
[clarification needed] Designed to operate at depths of up to 1,000 meters the hull compresses as it sinks to match the pressure from the seawater.