The ESO 3.6-metre Telescope has supported many scientific achievements and presented ADONIS, one of the first adaptive optics system available to the astronomical community in the 1980s.

HARPS is a fibre-fed high resolution echelle spectrograph dedicated to the discovery of extrasolar planets.

[10] The telescope was also involved in solving a decades-old mystery regarding the mass of Cepheid variable stars.

[11] The discovery of the extrasolar planet Gliese 581 c by the team of Stéphane Udry at University of Geneva's Observatory in Switzerland was announced on April 24, 2007.

[12] The team used the telescope's HARPS spectrograph, and employed the radial velocity technique to identify the planet's influence on the star.