Purple Sky at Night: Astronomer’s Delight!

This scene shows an arresting purple sky streaked with star trails over Cerro Pachón, the site of the Gemini South telescope (right) and the 4.1 meter Southern Astrophysical Research telescope (SOAR, left), both programs of the NSF’s Optical Infrared Astronomy Research Laboratory. From this mountaintop perch, which lies at an altitude of 2,737 meters (8980 ft) in the Chilean Andes, the 8.1-meter Gemini South telescope can survey the Southern sky — complementing the view from Gemini North atop Maunakea in Hawaiʻi. Together, these astronomical twins can access the entire night sky.