A Triangle of Satellite Flares Near Gemini North

Like many observatories, Gemini North sits in a remote area of the world to avoid the adverse effects of light pollution (the artificial brightening of the night sky often caused by the lighting in urban and suburban areas). Gemini North, one half of the International Gemini Observatory, supported in part by the U.S. National Science Foundation and operated by NSF NOIRLab, more specifically sits near the summit of Maunakea in Hawai‘i, high above the layers of clouds that act like an extra shield from city lights below. 

However, a different artificial light source can affect geographically protected telescopes: satellite constellations. To the right of Gemini North in this Image of the Week, satellite flares form a triangle under the Milky Way. Although this long-exposure image appears to capture a clear night sky, telescopes are typically a billion times more sensitive than the human eye. The majority of satellite constellations are invisible to humans, especially in regions that are already light-polluted. However, to the sensitive and time-exposed sensors on astronomical detectors — light detectors even more sensitive than those on the digital camera that captured this image — satellites appear as distracting streaks in their images, or as an overall brightening of the sky. You can learn more about how NSF NOIRLab is actively working to preserve the night sky near astronomical sites here. 

This image was captured during a photo visit with Jeff Warner, a photographer who documents the ever-changing skyscape in the rise of satellite launches. You can learn more about Jeff’s work here.