Measuring accurate distances of stars throughout the Milky Way is very different from measuring distances on earth.

To measure the immense distances between stars to any accuracy, tiny angular changes over very long baselines must be calculated. So to detect these subtle changes, NASA  needs to measure the position of stars with several hundred times greater precision than what has been possible in the past.

Central to NASA’s space mission are Australian-built retro-reflectors made by the Australian Centre for Precision Optics, based at CSIRO Materials Science and Engineering at Lindfield in Sydney, New South Wales. They reflect light back precisely to where it came from – regardless of incidence angle.

Dubbed ‘double corner cubes’, the reflectors aims to enable the detection of new planets by accurately mapping the stars and looking for any sign of ‘wobble’ in their positions. (Wobbling stars often indicate that gravity from orbiting planets is tugging at them).

The reflectors’ geometry – accurate to within five-thousandths of a millimetre- will enable precise relative positions of far-off stars to be measured by bouncing lasers between telescopes.

Although other corner cubes exist, NASA needed precision and resilience in the harsh operating environments of both deep space and the initial launch. These requirements are where ACPO’s skills in precision optics fabrication, coating, measurement and assembly make the difference.

Read more about Creating precision optics.