IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun) is a Japan Aerospace Exploration Agency (

JAXA The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into o ...

) experimental spacecraft. The spacecraft was launched on 20 May 2010, aboard an

H-IIA H-IIA (H-2A) is an active expendable launch system operated by Mitsubishi Heavy Industries (MHI) for the Japan Aerospace Exploration Agency. These liquid fuel rockets have been used to launch satellites into geostationary orbit; lunar or ...

rocket, together with the ''Akatsuki'' (Venus Climate Orbiter) probe and four other small spacecraft. IKAROS is the first spacecraft to successfully demonstrate

solar sail Solar sails (also known as light sails and photon sails) are a method of spacecraft propulsion using radiation pressure exerted by sunlight on large mirrors. A number of spaceflight missions to test solar propulsion and navigation have been ...

technology in interplanetary space. On 8 December 2010, IKAROS flew by

Venus Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never f ...

at a distance of , successfully completing its planned mission, and entered its extended operation phase.

Purpose

The IKAROS probe is the world's first spacecraft to use

ing as the main propulsion. It was designed to demonstrate four key technologies (comments in parentheses refer to figure): # Deployment and control of a large, thin solar sail membrane (grey-blue areas numbered 3) # Thin-film solar cells integrated into the sail to power the payload (black rectangles numbered 4) # Measurement of acceleration due to

radiation pressure Radiation pressure is the mechanical pressure exerted upon any surface due to the exchange of momentum between the object and the electromagnetic field. This includes the momentum of light or electromagnetic radiation of any wavelength that is a ...

on the solar sail #

Attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlli