LightSail, a space vehicle that uses solar sailing as its propulsion system, is set to launch April, 2016. If successful, the LightSail will pave the way for using solar sails for practical, low-cost space travel and, in the distant future, even interstellar journeys. The mission is the product of the Planetary Society and will be launched by the SpaceX Falcon Heavy rocket, making it a private sector operation.
Solar sailing appears to be the most natural form of propulsion for humans. For hundreds of years, people have used wind to sail across the ocean to explore the Earth.
Solar sailing is essentially the same thing.
The LightSail craft will unfurl a metallic-looking sail. The sail will catch energy from the sun, which will push it away from the Earth deep into space. We can feel the pressure of photons every day when we go outside. In space, with a large enough area to catch photons, that pressure is enough to propel an object to tremendous speeds, theoretically.
LightSail’s sail will cover 32 square meters (344 square feet) and should be big enough to be seen from earth (and seen below).
The controls will be handled from a three-unit CubeSat called Prox-1 after launch.
One of biggest merits of LightSail’s technology is the cost. The LightSail mission will cost a projected $4 million dollars, since it will not require fuel once in orbit.
Right now, the worst problem for sun-powered propulsion is terrible luck.
The idea of a solar sail has been around for quite some time now. The Planetary Society attempted to launch a similar vehicle called the Cosmos 1 in 2005, but it was lost in the sea when Russian booster rockets failed. In 1999, Russia attempted another experiment using the sun’s light for propulsion from its Mir Space Station, but the device jammed and burned up in the atmosphere. As a result of this mishaps, solar sail technology has been set back a number of years.
But it has worked great in science fiction.
Science Fiction fans might note that solar sails have made appearances in both Star Trek and Star Wars. Count Dooku used a solar sail to escape from battle in Star Wars: Episode 2. In Star Trek Deep Space Nine, Commander Sisko rebuilds an ancient Bajoran solar sailing ship in the episode: Explorers.
If the LightSail mission is a success, the technology might be improved and one day used to send vehicles into the depths of the galaxy.
(Image Credits: Planetary Society and Rick Sternbach)