Approaching cm/sec calibration of high resolution astronomical spectrograph

Radial Velocity measurements have demonstrated to be the most successful way of finding extra solar planets; this technique has reported the larger quantity of exoplanet so far detected. Finding Earth like type exoplanets demands a cm/sec reproducible spectrograph calibration. A Laser Frequency Comb (LFC) calibration system has been developed and tested in several occasions with the HARPS spectrograph at the 3.6m telescope on La Silla ESO Observatory since January 2009. The LFC shows a number of advantages compared to other traditional calibration sources.