The 3.58-metre New Technology Telescope (NTT) appears at night in action. The Orion's belt and the pink-red Orion Nebula (M42) are right above the telscope head. Sirius (the brightest star in the night sky) appears higher up in the sky. Located in La Silla Observatory, Operated by the European Southern Observatory (ESO), the telescope sits at about 2400 metres above sea level on the outskirts of the Chilean Atacama Desert. This telescope housing was considered a technological breakthrough when completed in 1989. La Silla was ESO's first observatory, inaugurated in 1969. The NTT was the first telescope in the world to have a computer-controlled main mirror (active optics).