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In its hunt for alien life, Nasa has turned to glitter to help make contact with new worlds.

The space agency says the huge mirrors it is currently using are expensive and difficult to build.

Instead, it wants to test the use of shimmering clouds of glitter-like particles to view stars and exoplanets.

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In its hunt for alien life, Nasa has turned to glitter to help make contact with new worlds. This image shows white light reflected off of a glitter mirror onto a camera sensor. Researchers tested this in a laboratory as part of the concept of 'Orbiting Rainbows,' a low-cost solution for space telescope mirrors

The concept, called Orbiting Rainbows, could enable high-resolution imaging at a fraction of the cost.

'It's a floating cloud that acts as a mirror,' said Marco Quadrelli from JPL, the Orbiting Rainbows principal investigator. 'There is no backing structure, no steel around it, no hinges; just a cloud.'

In the proposed system, the small cloud of glitter-like grains would be trapped and manipulated with multiple laser beams.

The trapping happens because of pressure from the laser light caused by the momentum of photons.

Their momentum translates into two forces: one that pushes particles away, and another that pushes the particles toward the axis of the light beam.

The pressure of the laser light coming from different directions shapes the cloud and pushes the small grains to align in the same direction.

In a space telescope, the tenuous cloud would be formed by millions of grains, each possibly as small as fractions of a millimetre in diameter.

Such a telescope would have a wide adjustable aperture, the space through which light passes during an optical or photographic measurement.

Scientists at Nasa made a mirror surface out of glitter to test the idea of using a cloud of reflective particles as a space telescope mirror. They took images of two light sources using this mirror in a laboratory at Rochester Institute of Technology

'You deploy the cloud, trap it and shape it,' Quadrelli said.

The original idea for a telescope based on a laser-trapped mirror was proposed in a 1979 paper by astronomer Antoine Labeyrie at the College de France in Paris.

Now, the Orbiting Rainbows team is trying to identify ways to manipulate and maintain the shape of an orbiting cloud of dust-like matter using laser pressure.

Because a cloud of glitter specks is not a smooth surface, the image produced from those specks in a telescope will be noisier - with more speckled distortion - than what a regular mirror would generate.

To address this, researchers are developing algorithms to take multiple images and computationally remove the speckle effect from the glitter.

Orbiting Rainbows: NASA's space telescope mirror concept

To test the idea, co-investigator Grover Swartzlander, an associate professor at the Rochester Institute of

Technology in New York, and his students spread glitter on a concave lens in the laboratory. His team used lasers to represent the light from a double star system.

They pointed the speckled mirror at the simulated stars, then used a camera to take pictures.

With many exposures and lots of processing, an image of the two 'stars' emerged using the glitter mirror.

'This is a major achievement,' Quadrelli said. 'This demonstrates a highly controlled experiment in which we were able to do imaging in the visible light spectrum.'

Orbiting Rainbows has not yet been demonstrated in space. 

For a test in low-Earth orbit, the researchers would deploy a telescope with a small patch of particles, no larger than a bottle cap, to show that it can be trapped and shaped to reflect light.

The next step would be to make many of these patches and synthesise an aperture with which to do imaging.