How long is the average life-time of a telescope?
It depends very much on the project, its design, objectives and funding. For the whole of ESO’s existence, the most ambitious astronomical projects have demanded ever larger investments that cannot be afforded only by a single country. In order to “recover” such important investments, a facility should operate for at least a couple of decades at the forefront of astronomy, before the next generation of telescopes takes over. After that, the telescopes continue operating, typically with new instruments and often dedicated to specific observing programmes. This is the case with the ESO 3.6-metre telescope, commissioned in 1977. It was for many years the largest European telescope and one of the largest telescopes in the southern hemisphere. It is now home to the world’s foremost exoplanet hunter: HARPS (High Accuracy Radial velocity Planet Searcher).
