In a teleconference held on Wednesday, members of the LightSail 2 team declared that the solar sailing mission was a success. The citizen-funded spacecraft is the highest performing solar sail to date and the first to demonstrate the ability to orbit the Earth in a controlled manner.
This is a very exciting day for us and for me personally – Bill Nye, executive director of the Planetary Society, organizer of the mission.
LightSail 2 is the latest demonstration of solar sail technology, which uses the gentle pressure of photons, light particles, on light and reflective surface to propel a spacecraft through space, similar to the way that the wind pushes a sailboat in the sea. However, instead of canvas, solar candles are made of thin sheets of Mylar, the same crumpled silver material that is often used for helium inflated balloons.
Scientists expect sunlight to allow sails to accelerate at much higher speeds than those provided by traditional propulsion methods that use chemical or nuclear fuel. LightSail 2 puts it into practice through a small satellite with a sheet of 32 square meters of very thin, light and, reflective polyethylene terephthalate (PET) that should allow the device to be moved by the simple impulse of the sun’s photons.
By tracking the location of the spacecraft, the team discovered that it had traveled 1.7 kilometers farther from Earth in just four days thanks to the mild influence of sunlight. This is the first time that solar propulsion has been successfully demonstrated in the Earth’s orbit.
The objective of this project is to demonstrate that solar sails can be used to drive small satellites called CubeSats. These small satellites weigh just 1 kilogram and can carry scientific instruments such as cameras. Specifically, LightSail 2 takes a 5-kilogram CubeSat to a controlled orbit around the Earth. LightSail 2 was launched on June 25, 2019. Last week, it was successfully deployed to its total area of approximately 32 square meters about the size of a boxing ring.
The spacecraft orbits the Earth along an elliptical path. Powered by sunlight, the spacecraft will reach a higher orbit until August 23, 2019. As the maximum distance between the Earth and LightSail 2 increases, part of its orbit will approach Earth. Eventually, the ship will re-enter Earth’s atmosphere and burn, concluding its mission.