Hexapod-Telescope, Optical telescope at Cerro Murphy Observatory, Chile

The Hexapod-Telescope was a 1.5-metre Ritchey-Chrétien telescope whose 50 mm-thick Zerodur primary mirror rested on 36 piezo actuators. Instead of a two-axis mount, six variable-length struts forming a Stewart platform carried the mirror cell, giving movement in all six spatial degrees of freedom. Carbon-fibre composites made it about ten times lighter than classical telescopes of the same aperture.

The Hexapod-Telescope was planned in the 1980s as a prototype for a new telescope concept and built in the 1990s by Krupp Industrietechnik, later Vertex Antennentechnik, with astronomers of the Ruhr University Bochum's Astronomy Institute led by Rolf Chini. Its Zerodur optics came from Carl Zeiss in Jena. After testing in Bochum, it was moved in 2006 to the Cerro Armazones Observatory in Chile and decommissioned in 2017.

The name comes from the six extensible struts, a Stewart platform, that support the mirror cell. The design was chosen even though pointing a hexapod is far more complex than a conventional two-axis mount, because the parallel structure gives high stiffness and repeatability. Visitors to Cerro Armazones see a decommissioned prototype that tested ideas later considered for very large telescopes.

The HPT stands at the Cerro Armazones Observatory in the Atacama Desert of northern Chile, on the summit of Cerro Murphy, a secondary peak of Cerro Armazones. A dedicated control building was erected beside it for the instrument. The telescope is decommissioned and no longer observes; its spectrograph BESO now works on the 1.5-m telescope at the same observatory.

The instrument includes the Bochum Echelle Spectrograph, a specialized device developed in partnership with Heidelberg-Königstuhl Observatory. This spectrograph breaks down starlight into its different colors to analyze stellar properties.