This year, NASA loaded a microwave-sized device equipped with an ultra-thin, four-piece solar sail measuring 860 square feet (75 square meters) onto a rocket.
The launch took place on April 23. The solar sail, called the Advanced Composite Solar Sail System (ACS3), was able to deploy its booms and sails in late August after an initial failed attempt.
“Now that its reflective sail is fully deployed in orbit, the Advanced Composite Solar Sail System can be seen in the night sky from many locations around the world!” tweeted Arezu Sarvestani of NASA. The reflective surface of ACS3 can sometimes be as bright as Sirius, one of the brightest stars in the night sky.
To help curious people find the experimental craft in the sky, the space agency has added a new feature to its mobile app. It provides a local schedule of the spacecraft’s passage (when it will be visible to the naked eye), and uses augmented reality to point the phone to the desired area of the sky (relevant for iOS users).