First laser measurements of Europe's Galileo satellites made from Chile

The first laser ranging of Europe's new Galileo navigation satellites has been achieved from Concepción in Chile. Laser contact with the satellites at an altitude of 23 230 km has provided distance measurements with subcentimetre accuracy. The Transportable Integrated Geodetic Observatory, TIGO, in Concepción, performed the world's first laser ranging to the first Galileo satellite on 27 November at 02:45 GMT, and to the second satellite two days later at 10:05 GMT, using a near-infrared laser beam. TIGO is equipped for various observations: in 2006 its radio telescope monitored ESA's first Moon mission, SMART-1, during its end-of-mission impact on the lunar surface. Laser reflectors work like motorway 'cat's eyes' The laser ranging proceeded like a planetary-scale video game: working from orbital predictions provided via the Navigation Office at ESA’s European Space Operations Centre, Darmstadt, Germany, the TIGO team, led by Michael Häfner and Marcos Avendaño, took aim with their laser and fired, having first calibrated their laser using Europe's first test navigation satellite, GIOVE-A. Like many modern satellites, the Galileo satellites are fitted with reflectors that work like motorway 'cat's eyes', to bounce the laser pulse back where it came from.