Atmospheric satellite

An atmospheric satellite (US usage, abbreviated atmosat) or pseudo-satellite (British usage) is an unmanned aerial vehicle (UAV) that operates in the atmosphere at high altitudes for extended periods of time. Atmosats are generally powered by solar panel arrays and rechargeable batteries or fuel cells, though a balloon-based system is also under development. Atmospheric satellites are distinguished from low Earth orbit satellites, which orbit above the atmosphere.

Development history

The initial goals under the NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project were to demonstrate sustained flight at an altitude near 100,000 feet and flying non-stop for at least 24 hours, including at least 14 hours above 50,000 feet. The early development path of atmospheric satellites included the NASA Pathfinder (exceeding 50,000 feet in 1995), the Pathfinder Plus (80,000 feet in 1998), and the NASA Centurion which was modified into a prototype configuration for the NASA Helios (96,000 feet in 2001). An Airbus/Qinetiq Zephyr clocked up a 14-day flight in the summer of 2010 and in 2014 a Zephyr 7 stayed up for 11 days in the short days of winter whilst carrying a small payload for the British Ministry of Defence. In 2014, the development goals of Titan Aerospace, purchased by Google, included operation at altitudes exceeding 60,000 feet for as long as five years.