Golden trees perfectly reflected in mirror like Blea Tarn in autumn, Lake District National Park, Cumbria, England, United Kingdom, Europe

A perfectly still Maligne Lake, Jasper National Park, UNESCO World Heritage Site, Alberta, Canada, North America

Perfectly still Buttermere at sunset, Lake District National Park, UNESCO World Heritage Site, Cumbria, England, United Kingdom, Europe

A fishing boat on a perfectly calm Indawgyi Lake in northern Myanmar on a misty afternoon, Myanmar (Burma), Asia

Mount Hood, part of the Cascade Range, perfectly reflected in the still waters of Trillium Lake, Oregon, United States of America, North America

Sun perfectly aligned at sunset on Sultanahmet Camii Mosque dome, UNESCO World Heritage Site, Istanbul, Turkey, Europe

Ra Gusela mountain at Passo Giau and the sun starbeam perfectly reflected in an alpine lake, Dolomites, Italy, Europe

Mount Hood, part of the Cascade Range, perfectly reflected in the still waters of Trillium Lake, Oregon, United States of America, North America

Mount Hood, part of the Cascade Range, perfectly reflected in the still waters of Trillium Lake, Oregon, United States of America, North America

Mount Hood, part of the Cascade Range, perfectly reflected in the still waters of Trillium Lake, Oregon, United States of America, North America

Green forest and chapel perfectly reflected in Lake Braies (Pragser Wildsee) in summer, Dolomites, South Tyrol, Italy, Europe

Mount Hood, part of the Cascade Range, perfectly reflected in the still waters of Trillium Lake, Oregon, United States of America, North America

Long-beaked Common Dolphin (Delphinus capensis) leaping - note reflection on perfectly calm water surface -in the Gulf of California (Sea of Cortez), Mexico.

The Full Moon rising on December 22, 2018, the day after the winter solstice, in a perfectly clear sky and over the distant horizon to the northeast over the snow-covered prairie. Some cows are grazing at left! The top edge of the Moon has a green rim and the bottom edge a red rim, from atmospheric refraction. But it made for a Christmas-coloured Moon ornament on the horizon! The dark lunar mare and even the bright rays splashing from Tycho at bottom are visible.

A composite of the November 11, 2019 Transit of Mercury across the disk of the Sun, on a day with no sunspots on the Sun. The temperature was about -20�8 C to -15�8 C this morning but the sky was perfectly clear.

Man sells perfectly grilled fish skewers at the night market, Luang Prabang, Luang Prabang Province, Laos, Asia

Perfectly grilled coiled sausage on a barbeque, Paul da Serra, Madeira, Portugal

perfectly camouflaged. Robust Ghost Pipefish, Solenostomus cyanopterus, mimic the seagrass in which they live.

Bill Russell lines up his kayak perfectly over some falls on the Kern River, near Kernville, California.

An immature black-winged stilt (Himantopus himantopus) with its beak in the water walks through the shallows of a perfectly calm lake, matched by its own reflection. Shot with a Nikon D800 at Ranthambore National Park in India; Rajasthan, India

Reef resilience: a perfectly healthy coral ball after the bleaching episode of April 2024. The damselfish hotel withstood the heat in less than 3 meters of water. S-shaped pass, Mayotte

Reef resilience: a perfectly healthy coral ball after the bleaching episode of April 2024. The damselfish hotel withstood the heat in less than 3 meters of water. S-shaped pass, Mayotte

Calderón (Globicephala macrorhynchus). Breeding with an adult, probably his mother swimming on the surface. The fetal lines of the newborn can be perfectly observed. Tenerife, Canary Islands.