Bertrand Koehler held his first telescope at age 13. It seems I was almost realizing my dream of being an astronaut embarking on an unusual rocket!” Credit: Bertrand Koehler. Bertrand Koehler at La Silla Observatory in 1986, serving as an ‘astronomer on duty’: “A fantastic opportunity for a young engineer/astronomer”. Credit: Bertrand Koehler. “A judge came down from the city and asked to stop the VLT work.