A celestial arch illuminates the desert
The stunning arch of the Milky Way stretches across the Chilean night sky, accompanied by the Magellanic Clouds on the left and admired from the control building of ESO’s Paranal Observatory, home to the Very Large Telescope (VLT).
The Milky Way is between 100 000 and 200 000 light-years in diameter and is made up of billions of other stars besides our Sun. The galactic centre, seen here as the bright area to the top-left of the Milky Way arc, is 27 000 light-years away. It takes the Sun almost 250 million years to complete an orbit around the Milky Way centre, and it has done so approximately 20 times since it formed.
The Large and Small Magellanic Clouds are just two of the Milky Way’s galactic neighbours. They orbit our Galaxy at a distance of about 160 000 and 200 000 light years, respectively. These dwarf galaxies have an irregular shape, possibly due to gravitational interactions between each other and with our Galaxy.
If the telescopes can be regarded as the eyes of the Paranal Observatory, the control building would be its brain. Along with various offices, it hosts the control room, from which all telescopes and instruments are controlled and pointed towards the cosmic objects to be observed, and where a first evaluation of the collected data is performed.