Sunset over Haleakala observatories. Sunset colours in the sky seen from the summit (3050 metres) of the Haleakala volcano on Maui, Hawaii. The telescopes, part of the Haleakala High Altitude Observatory, include the under-construction Daniel K. Inouye Solar Telescope (DKIST, left), operated by the National Solar Observatory, and the Advanced Electro Optical System (AEOS) Telescope (right), operated by the Air Force Research Laboratory (AFRL). Hawaii's mid-Pacific location and the high elevation provide excellent viewing conditions. Photographed on 16 August 2015.