Perfectly framed

Astronomers mostly focus their attention on the sky, but sometimes it’s worth looking around our planet, too. At night, the star-spangled sky over Chile’s Atacama Desert steals the limelight, but once the barren landscape basks in sunlight again, other marvels are revealed.

This Picture of the Week, for instance, could easily feature in a travel magazine. It is taken from Pukará de Quitor (Fort of Quitor), a stone fortress built centuries ago by the Licán Antai community, also known as Atacameños. You find it near San Pedro de Atacama, not far from where the Atacama Large Millimeter/submillimeter Array (ALMA) is housed, the radio telescope array which ESO operates together with its international partners. In this picture, the arch of the fortress is framing the Licancabur volcano, which looms up next to Chile’s border with Bolivia. On the mountain, other archaeological sites have been found, and its summit crater hides one of the highest lakes in the world.

Now close your eyes and imagine you are standing right there, on the stones of Pukará de Quitor. Are you surrounded by blue skies and terracotta stones? Or by a pitch black sky full of stars? Whichever you choose, remember that you are looking back in time. This archaeological site dates all the way back to the 12th century, so these stones have been standing here for over 900 years. And the light of the stars has travelled hundreds or even thousands of years before it reaches us. What a privilege to be able to see it!