The Calar Alto Observatory (Centro Astronómico Hispano en Andalucía or "Spanish Astronomical Centre in Andalusia") is an astronomical observatory located in Almería province in Spain on Calar Alto, a 2,168-meter-high (7,113 ft) mountain in the Sierra de Los Filabres subrange of the Sierra Nevada.
It was named the "German–Spanish Astronomical Centre" (in Spanish, Centro Astronómico Hispano-Alemán (CAHA); in German, Deutsch-Spanisches Astronomisches Zentrum).
[4] The CARMENES survey (Calar Alto high-Resolution search for M-dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) is a project to examine approximately 300 M-dwarf stars for signs of exoplanets with the CARMENES instrument on Calar Alto's 3.5m telescope.
Operating since 2016, it aims to find Earth-sized exoplanets around 2 ME (Earth masses) using Doppler spectroscopy (also called the radial velocity method).
[5][6] Close to a hundred minor planets have been discovered at Calar Alto by astronomers Luboš Kohoutek, Kurt Birkle, Ulrich Hopp, Johann Baur, Krisztián Sárneczky, Gyula Szabó, Felix Hormuth and Hermann Boehnhardt.