IKAROS: Japan Solar Sail Unfurls
Japanese 'Space Yacht' Deployed: First of Its Kind
The Japanese Aerospace Exploration Agency (JAXA) has unfurled the first-ever solar sail. The IKAROS (Interplanetary Kite-craft Accelerated by Radiation of the Sun) has a super-thin 14mx14m sail that is thinner than a strand of human hair.
A solar sail uses pressure from photons to move a craft through the frictionless environment of outer space. Should JAXA's test prove successful, the IKAROS would change the future of space travel: spacecraft would no longer have to carry a fuel supply for locomotion once in space; that fuel mass is a limiting reagent in spaceship design.
Japan Aerospace Exploration Agency (JAXA) 'confirmed the full expansion of the sail and electric generation with thin film solar cells at about 7.7 million kilometres from Earth,' it said in a statement. JAXA will continue monitoring and studying 'navigation technology using the solar sail', it said.
The principle of solar sailing is a simple one. Photons, or particles of light, falling on a highly reflective, ultra-thin (in this case, just 7.5 microns) surface will exert a pressure.
The force is tiny but continuous, and over time should produce a considerable velocity.