Laser-light mirror inspires design for space telescopes

Nature : A new type of mirror may revolutionize space telescopes, but only if a number of significant engineering challenges are overcome, reports David McGloin in Nature. More than 35 years ago astronomer Antoine Labeyrie proposed building a space-based mirror consisting of millions of microscopic particles held in place by laser light. Such a mirror could “self-heal” in the event of being hit with debris and have a diameter tens of meters greater than more “standard” space telescopes. Now in Physical Review Letters , Tomasz Grzegorczyk and colleagues describe their first step toward this goal. They have created an optically bound structure of about 150 spherical polystyrene particles, each with a diameter of 3 micrometers, that can act as a mirror. So far the mirror can only work in water and is unstable over long time periods, and the image quality is too crude for optical astronomy. The researchers have high hopes that those issues can be overcome.