Ashley Cooper / Sunflower next to the PS20 solar thermal tower, the only such working solar tower currently in the world. Sanlucar La Mayor, Andalucia, Spain. May 2011

Ashley Cooper / Heliostats, large reflective mirrors directing sunlight to the PS20 solar thermal tower, the only such working solar tower currently in the world. Sanlucar La Mayor, Andalucia, Spain. June 2011

Tim Fitzharris / Western Juniper (Juniperus occidentalis) and Jeffrey Pine (Pinus jeffreyi) trees, Phipps Peak, Eldorado National Forest, California

Tim Fitzharris / Dana Plateau from Ellery Lake, Sierra Nevada, Inyo National Forest, California

Tim Fitzharris / Dana Plateau from Ellery Lake, Sierra Nevada, Inyo National Forest, California

Tim Fitzharris / Arch and Milky Way, Alabama Hills, Sierra Nevada, California

Floris van Breugel / Temple Crag above Second lake, one the of the Big Pine lakes below the Palisade basin, John Muir Wilderness, Sierra Nevada, California, USA, May

Floris van Breugel / Sunrise over Mt Morrison in the far distance, near Convict Lake, Sierra Nevada, California, USA January

Floris van Breugel / The granite mountains of the high sierra, with clouds at sunset. Royce Lakes seen from Feather Peak, John Muir Wilderness, Sierra Nevada, California, September 2009

Tim Fitzharris / Full moon over Mono Lake with wind and rain eroded tufa towers and the eastern Sierra Nevada Mountains in the background, California

Tim Fitzharris / Sun illuminating the Alabama Hills, California

Jim Brandenburg / Giant Sequoia (Sequoiadendron giganteum), General Sherman tree in Sequoia National Park, California