It was back in May we last heard about NASA launching its Advanced Composite Solar Sail System, which if successful could revolutionize space travel in the solar system and perhaps even further out into the seemingly endlessness of the universe.

NASA launched a tiny CubeSat on the back of Rocket Lab's Electron rocket on April 23, and reported the next-generation technology was successfully placed 600 miles above the surface of Earth in a Sun-synchronous orbit. The CubeSat was then ready to move onto the next part of its mission, the lengthy unfurling process that will eventually result in the sail appearing as a square that's approximately 860 square feet, or about half the size of a tennis court.
NASA has now provided an update on the mission, writing the solar sail is "now fully deployed in space after a successful test of its sail-hosting boom system." The space agency goes on to explain aboard the solar sail are four cameras that captured panoramic views of the reflective saily and supporting composite booms. NASA states on September 4 images from these cameras will be published to showcase the achievement.
So, why do all this? The solar sail is to test sunlight propulsion, which is the means of using photons as a way of moving around space.

"It's quite simple: the Sun radiates photons, or light, in all directions continuously, and when these photons collide with the solar sail, they bounce off, generating a tiny amount of momentum that's transferred into the sail and creates push. With a surface level of approximately half a tennis court and the means of controlling the direction the sail is facing, the push could be enough to have an extremely low-cost means of solar system transportation.
If this technology proves to be viable, researchers have previously theorized that solar sails could be used for cheap, high-speed missions to distant locations, as Earth will be able to blast the solar sail with a constant stream of photons, speeding up the spacecraft to speeds beyond chemical rockets," explains my previous article