Enrique Lopez-Tapia / The last light of day illuminating the summit of Mount Everest, Sagarmatha National Park, Khumbu, Himalayas, Nepal, October 2011.

Aflo / N-21604 Mount Everest at dawn with full moon, Sagamartha NP, Himalayas, Nepal.

Grant Dixon / Wind cloud over Mount Everest seen from Sagarmatha National Park, Nepal

Gavin Maxwell / Rongbuk monastery with Mount Everest in background, Tibet, June 07. 'Wild China' series

Gavin Maxwell / Rongbuk Glacier with Mount Everest, Tibet, June 07. 'Wild China' series

Michael Pitts / Ama Dablam, Mount Everest NP, Nepal

Colin Monteath / Mountaineer enjoying the view of Mt Everest and the Himalayan Mountains at sunset from Gokyo Ri, Khumbu, Nepal

Colin Monteath / Panoramic view from Mt Makalu, elevation 8,462 meters, to Mt Everest, elevation 8,850 meters, at dawn, reflected in small lake, Khama Valley, Kharta region, Tibet

Colin Monteath / Panoramic view from Mt Makalu, elevation 8,462 meters, to Mt Everest, elevation 8,850 meters, at dawn, reflected in small lake, Khama Valley, Kharta region, Tibet

Colin Monteath / Wildflowers growing on moraine terrace beside Kangshung Glacier, with Mt Chomolonzo in background, east of Mt Everest, Tibet

Leo & Mandy Dickinson / Aerial view of Mount Everest, Nuptse ridge in foreground, Himalayas, Nepal

Leo & Mandy Dickinson / Mount Everest before dawn, Himalayas, Nepal