ESPRESSO (Echelle SPectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations) is a third-generation, fiber fed, cross-dispersed, echelle spectrograph for the European Southern Observatory's Very Large Telescope (VLT) is the successor of a line of echelle spectrometers (CORAVEL, Elodie, Coralie, HARPS). It measures changes in the light spectrum with great sensitivity, and will be used to search for Earth-like planets via the radial velocity method. For example, our Earth induces a radial-velocity variation of 9 cm/s on our Sun; this gravitational "wobble" causes minute variations in the color of sunlight, invisible to the human eye but detectable by the instrument. The telescope light is fed to the instrument via a Coude-Train optical system and fibers. ESPRESSO is located in t