Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2001 August 31
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The Flight Of Helios
Photo Credit: Carla Thomas, courtesy DFRC, NASA

Explanation: Solar-powered, remotely piloted, and flying at about 25 miles per hour, NASA's Helios aircraft, is pictured above at 10,000 feet in skies northwest of Kauai, Hawaii on August 13. This ultralight propeller driven aircraft, essentially a flying wing with 14 electric engines, was built by AeroVironment Inc. Covered with solar cells, Helios' impressive 247 foot wide wing exceeds the wing span and even overall length of a Boeing 747 jet airliner. Climbing during daylight hours, the prototype aircraft ultimately reached an altitude just short of 100,000 feet, breaking records for non-rocket powered flight. Helios is intended as a technology demonstrator, but regular, long-duration flights at that altitude could be used for environmental monitoring missions and, communications relays. In the extremely thin air 100,000 feet above Earth's surface, the flight of Helios also simulates conditions for winged flight in the atmosphere of Mars.

Tomorrow's picture: Magnetars


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
& Michigan Tech. U.