English: This picture shows an engineering rendering of the main mechanical and optical components of the ESPRESSO instrument on ESO’s Very Large Telescope at the Paranal Observatory in northern Chile. ESPRESSO will be an ultra-precise spectrograph that is capable of combining light from all four VLT Unit Telescopes to create a virtual 16-metre aperture telescope. The instrument is mounted inside a vacuum vessel that is in turn inside two thermal isolation enclosures to shield it from external disturbances. The extensions from the top of the instrument are parts of the instrument’s two cameras, one each for the red and blue parts of the spectrum.