A week of major space milestones---NanoSail D2 deployed

                 It was a week of major space milestones. On Thursday---two days prior to the launch of Kounotori-Japan's unmanned spacecraft to the International Space Station--Nasa's first solar sail designated as NanoSail D2 deployed its 100 square foot polymer sail in low earth orbit and is operating as planned.

                 A project of mainly Nasa's Marshall Space Flight Centre, it was launched on November 19,2010, as a payload of a microsatellite, FastSat. The solar sail was successfully ejected from FastSat a week later and is expected to remain in low earth orbit between 70 and 120 days depending upon atmospheric conditions.

                Weighing four kgs, the primary aim of the mission is to demonstrate the use of solar power for space flight. The advantage of using solar power is that it would mean less propellants which transalates into having more payload in the long run.  Additonally, it will also show how a compact solar sail boom can be deployed successfully.

                In plain terms, solar sails use sunlight to propel vehicles through space much like sailboats rely on wind to push through the water. They propel a spacecraft by relying on energy from the sun. The sail constantly captures streaming solar particles with giant sails built from light weight reflective material. Over time, the spacecraft builds momentum from these particles' energy to provide thrust and travel in space.

                That is not all. According to Nasa, the mission results could be used on future large spacecraft missions to aid in deorbiting space debris created by decommissioned satellites without using propellants.

                Nasa attempted its first solar sail launch in August 2008, but it did not succeed because of the failure of the Falcon rocket,

                The world's first solar sail was launched by the Japan Aerospace Exploration Agency (Jaxa) named Ikaros (Interplanetary Kites Craft Accelerated by Radiation Of The Sun). On December 2010, seven months after its launch in May 2010, it passed by Venus at a distance of about 80,800 kms thus completing its planned mission. It then flew into its extended operation phase.

                The days ahead perhaps could see more space missions being launched with solar sails.

                Isro anything on the cards?