A Snowy Sunset

This panorama shows a menagerie of telescopes — including Gemini North (right), one half of the International Gemini Observatory, operated by NSF’s NOIRLab — basking in a glorious snowy sunset near the summit of Maunakea in Hawai‘i. The 8-meter-diameter Gemini North is visible at the right hand edge of this image, and the 3.8-meter-diameter United Kingdom Infrared Telescope is the leftmost telescope in view. Other telescopes are dotted along the ridge in the background, including the Subaru Telescope and the W. M. Keck Observatory. The Maunakea Observatories study phenomena across the electromagnetic spectrum, from radio to ultraviolet, and they all benefit from the dark, dry, still skies at the site. 

Gemini North — like its twin telescope Gemini South in the southern hemisphere — has silver-coated mirrors optimized for observing at mid-infrared wavelengths. Infrared observations from ground-based observatories are usually limited by water vapor in the atmosphere, which absorbs a large amount of the infrared light from stars and galaxies. Detailed ground-based infrared observations are consequently only possible at a handful of dry sites that generally lie at high altitude above most of the atmosphere, such as the summit region of Maunakea.