This simulated image shows how a cloud of glitter in geostationary orbit would be illuminated and controlled by two laser beams. As the cloud orbits Earth, grains scatter the sun's light at different angles like many tiny prisms, similar to how rainbows are produced from light being dispersed by water droplets. That is why the project concept is called "Orbiting Rainbows."
The cloud functions like a reflective surface, allowing the exoplanet (displayed in the bottom right) to be imaged. The orbit path is shown in the top right. On the bottom left, Earth's image is seen behind the cloud.
To image an exoplanet, the cloud would need to have a diameter of nearly 98 feet (30 meters). This simulation confines the cloud to a 3.3 x 3.3 x 3.3 foot volume (1 x 1 x 1 meter volume) to simplify the computations. The elements of the orbiting telescope are not to scale.
Orbiting Rainbows is currently in Phase II development through the NASA Innovative Advanced Concepts (NIAC) Program. It was one of five technology proposals chosen for continued study in 2014. In the current phase, Orbiting Rainbows researchers are conducting small-scale ground experiments to demonstrate how granular materials can be manipulated using lasers and simulations of how the imaging system would behave in orbit.