ESPRESSO is a new-generation spectrograph for ESO’s Very Large Telescope. The amazing ‘spectroscopic’ precision of this instrument will provide the community with new scientific capabilities which are unique world-wide. The instrument is built and delivered to ESO by the ESPRESSO Consortium in exchange of Guaranteed-Time Observations (GTO). This collaboration will focus and dedicate the GTO to two major scientific programmes: the search for rocky extra-solar planets in the habitable zone of their host stars and the determination of the possible variability of physical constants. In the latter case, the observations will make use of the capability of ESPRESSO to combine incoherently the light of up to four 8-m Unit Telescopes (UTs) of the VLT. This make ESPRESSO to the first optical instrument using a 16-m equivalent telescope.
The ESPRESSO Consortium is composed of Italian, Portuguese, Spanish and Swiss institutes. ESO contributes to the project as Associated Partner. The instrument is currently in the procurement phase. Assembly and integration will take place in 2015, and on-site installation and commissioning is planned for the second part of 2016. ESPRESSO will be opened to the scientific community by 2017.