Photo of the Day Archive

Kitt Peak National Observatory, one of the largest gatherings of astronomical instruments in the Earth's northern hemisphere, glows red under starry, late-night skies.

Sepia Saturday: Majestic storm clouds float above Sedona.

Monsoon rains nourish green fields in the foothills of the Chiricahua Mountains.

A horse grazes in a late-summer field beneath the San Francisco Peaks.

Black and White Wednesday: Lightning strikes over Caralampi Canyon.

O'Neill Butte, an iconic rock formation on the South Kaibab Trail, glows against the background of the Grand Canyon.

Sunlight peeks through early morning clouds and fog, illuminating the purple quartzites in Barnhardt Canyon.

Southwest synchronous fireflies perform a mating display along the Santa Cruz River, in Tumácacori National Historic Park.