NASA will use reflective particles and not mirrors to find planets or stars beyond the solar system. Researchers at JPL in Pasadena (California) believe this could allow for high-resolution imaging without the need to set up heavy and bulky mirrors. To image distant objects, telescopes use solid mirrors. Stargazing requires large and complex mirrors that are expensive to make. It is difficult to launch a space telescope because of their size and weight. Scientists at JPL wondered if Orbiting Rainbows could help to solve some of these issues. To help telescopes see exoplanets, stars and galaxies, they suggest using reflective particles of glitter-like material instead of mirrors. A glitter mirror was placed onto a camera sensor using white light. (Credit: G. Swartzlander/Rochester Institute of Technology) Orbiting Rainbows would enable high-resolution images at considerably lower costs, they say. Marco Quadrelli from JPL is the Orbiting Rainbow lead researcher. He said that it’s a floating cloud which acts as a mirror. Multiple laser beams could manipulate glitter. Scientists propose multiple laser beams to trap the shimmer-like grains within a small cloud. Laser light could trap particles using the momentum of photons, tiny particles of light. It would do this in two directions. One that pushes the particles away and one that moves them towards the axis. Different directions of laser light could be applied to the cloud. This would create pressure at different points, shaping it, and pushing small grains in the same direction. The cloud could be made up of millions of tiny grains that are just fractions of millimeters in diameter, using a space telescope. An appropriate telescope should have an adjustable aperture. This is the area through which light moves during optical or photographic measurements. If the concept is successful, future telescopes will have larger apertures than existing models. To test the possibility of using reflective particles in space telescope mirrors, scientists made a mirror out of glitter. (Credit: G. Swartzlander/Rochester Institute of Technology) Orbiting telescopes would be easier to deploy A telescope made for an Orbiting Rainbows system would be much simpler to package, transport and send into space compared to conventional ones. Quadrelli stated that “you deploy the cloud and trap it, and shape it.” It would be much easier to transport and ship an Orbiting Rainbows telescope than a conventional one. There are many structures found in nature with light-scattering or focusing features such as comet trails and rainbows. These phenomena were observed, and recent laboratory successes in optical trapping, manipulation, have all contributed to Orbiting Rainbows. French astronomer Antoine Emile Henry Labeyrie proposed the first telescope based upon a laser-trapped mirror embedded in a 1979. paper. Scientists at Orbiting Rainbow are trying to figure out how to control and maintain an orbiting cloud made up of particles similar to dust using laser pressure. This will allow it to function as an adaptive surface that has useful electromagnetic characteristics. You will see more distortions. A cloud of glitter particles has a rough surface, which means that the images produced by telescopes using those specks will have more noise – more speckled distortion than would be created from regular mirrors. Scientists are developing algorithms that can take multiple images of the same object and then remove speckle effects from glitter using computers. Gover Swartzlander (associate professor, Rochester Institute of Technology), New York) and his students tested the concept by spreading glitter onto a concave lens. To represent the light of a binary star, they used lasers. A speckled mirror was pointed towards the stars and used a camera to capture pictures. The glitter mirror produced an image with the two stars after many exposures. Quadrelli stated that this was a significant achievement. It is a controlled experiment that allowed us to image in visible light. Radio-band and visible light signals. The technology can be more easily used for radio-band signals. The radio-band signal is one centimeter long, while visible light signals measure just nanometers. Therefore, the alignment and control of mirror grains will not be required. These characteristics allow for many Earth science applications, such as remote water sensing and earthquake detection. Darmindra Arumugam is a JPL employee and studies potential mechanisms to remote sense with Orbiting Rainbows. JPL’s optical design group has been developing adaptive optics methods that will be needed by the Orbiting Rainbows telescope. Scientists have explored diffractive as well reflective options for a telescope that is based on Orbiting Rainbows. They are currently focusing their efforts at achieving maximum frequency sensitivity. To demonstrate Orbiting Rainbows from low Earth orbit, scientists will deploy a telescope that has a tiny patch of particles. This is to prove it can trap light and shape it to reflect. NASA wrote: “The next stage would be to create many of these patches, and synthesize an aperture which can do imaging.” NASA video – Orbiting Rainbows is a lab demonstration of Orbiting Rainbows.
NASA uses glitter clouds to capture images of space worlds
