Scientists tested a prototype of a graphene solar sail

Solar radiation pressure coefficient.

The new prototype of the solar sail was developed by a team of researchers from the Delft University of Technology (Delft University of Technology) and the Estonian startup Scale Nanotech. A small-coin sail prototype was tested in microgravity at the ZARM tower of the University of Bremen. During the fall of the tower in a container with test equipment, weightlessness occurs for several seconds. This allows for experiments in which it is important not to have a strong gravitational component.

During artificial weightlessness, the 1 W laser was able to give the graphene «coin» an acceleration of 1 m/s2. The photons in the laser beam struck the surface of the prototype of the graphene sail and successfully accelerated it. An article about the experiment was published in the journal Acta Astronautica. The study was supported by the European Space Agency.

Mangalyaan solar sail.

The development of a Solar sail for space flight has been going on for years. In 2010, Japan launched the experimental spacecraft IKAROS with a sail area of 196 m2. Last year, the American non-profit organization «Planetary Society» launched the satellite Lightsail 2 with a solar sail on its third attempt.

The new development, unlike the previous ones, relies on graphene as the main material of the sail. More precisely, scientists have proposed a two-layer material. One layer of the sail is the thinnest, «atomic» thickness, 2D film, and also for weight reduction, perforated, and the second layer is a layer of graphene, which covers all the holes in the base film. The sail is solid, light, and strong. The reflective layer works its entire surface.

Where is the solar sail.

Scientists have estimated that the proposed graphene solar sail could well become the basis of the Breakthrough Starshot project for sending an interstellar sailing ship to Alpha Centauri. From a calculation of 14 m2 of sails per four grams of payload, the spacecraft could reach another star system in 30 years at 15% of the speed of light with an 8.5 GW laser.