IKAROS

Ikaros was the first space mission to be propelled by sunlight alone and the the first spacecraft to successfully demonstrate solar sail technology in interplanetary space. Ikaros is a Japanese experimental spacecraft and stands for Interplanetary Kite-craft Accelerated by Radiation of the Sun.

On 21 May 2010, the Japan Aerospace Exploration Agency (JAXA) launched a new kind of spacecraft. Named IKAROS, a short for Interplanetary Kite-craft Accelerated by Radiation of the Sun, this square-shaped craft is propelled through space using the Sun's energy in two different ways. It is embedded with thin solar cells that store sunlight as electricity and it also reflects light particles from the Sun. As the light particles bounce off the sail, they should provide the bulk of the momentum needed to propel the spacecraft.

IKAROS was launched on a H-IIA rocket from the Tanegashima Island in Japan. The rocket also carried an unmanned Venus probe called Akatsuki (Venus Climate Orbiter) and some small satellites. IKAROS will take the same trajectory as Akatsuki, but will pass by Venus and keep going on its way to the Sun.

The solar sail weighs about 315 kilograms in tidal and cost around £11 million to build and launch. A previous Japanese space organization, the Institute of Space and Astronautical Science demonstrated successful deployment of prototype solar sailed in 2004, but the propulsion system remains unproven. However, JAXA is confident that IKAROS will reach its ultimate destination. The challenge will be keeping the solar sail flat, stable and orientated correctly to take in enough sunlight.

The IKAROS membrane

The sail is made of four trapezoid-shaped panels of polymide, a light weight material abbot 32 micrometers thick. It is about 20 metros on the diagonal. One side of the sail has an aluminum layer, which reflects sunlight and provides thrust.

IKAROS's Competition

An independent non-profit organization called the Planetary Society has had its own solar sail project in the works, LightSail-1 is based on the NanoSail-D, a former NASA project. The Planetary Society hopes to launch LightSail-1 by the end of 2o10, but the launch is dependent on funding and whether rockets are available. The membrane will be made of Mylar and its body will comprise several tiny satellites called CubeSats.

IKAROS Mission

JAXA hopes IKAROS will deploy and show that power and thrust can be generated using solar cells. On 10 June 2010 JAXA confirmed the membrane had deployed. IKAROS took a picture of itself and replayed it back to mission control. The solar cells are also generating some power.

Long Term, IKAROS will spend six months travelling to Venus, then thee years to the far side of the Sun. Spacecraft may one day use solar power for propulsion, cutting down on expensive fuel and allowing for exploration. JAXA hopes to send a large sail to Juipter by 2020. IKAROS will investigate and measure space phenomenon and gather data on its way past Venus.

Related Books:

Solar Sails: A Novel Approach to Interplanetary Travel (Hardcover) by Giovanni Vulpetti (Author), Les Johnson (Author), Gregory L. Matloff
From Amazon.com, Amazon.co.uk, Amazon.ca

- Starsailing: Solar Sails and Interstellar Travel
by Louis Friedman from Amazon.com

- Solar Sailing: Technology, Dynamics and Mission Applications 
by Colin Robert McInnes from Amazon.com

Astronomy Books:

Did you know?

* The name is similar to Icarus, a figure in Greek mythology who melted his wings flying his wings too close to the Sun.

* A Solar Sail converts sunlight as a propulsion by means of a large membrane while a Solar 'Power' Sail gets electricity from thin film solar cells on the membrane in addition to acceleration by solar radiation.

IKAROS Links:

Small Solar Power Sail Demonstrator IKAROS: JAXA


Reference:

Picture of Ikaros: 30/08/2010