Saguaro cacti in the Sonoran Desert near Tucson, Arizona, USA (© Jack Dykinga/Minden Pictures)

Aurora Australis over the Halley VI Research Station in Antarctica (© Stuart Holroyd/Alamy)

Dawn sunlight and waves at Portland Bill lighthouse, Dorset (© Lee Pengelly/Getty Images Plus)

Male Atlantic puffin gives his mate nesting material, Skomer Island (© Danny Green/Minden Pictures)

Two rhinos and an oxpecker bird in the Amakhala Game Reserve in South Africa (© Robert Harding World Imagery/Offset)

Christmas tree farm in Ontario, Canada (© FatCamera/Getty Images Plus)

The Pinnacles at Nambung National Park, Western Australia (© Frank Krahmer/Getty Images Plus)

Los Alcornocales forest, Málaga, Spain (© Andrés M. Domínguez/Minden)

A scooter adorned with multiple mirrors, lights and air horns (© stocknshares/Getty Images)

Close-up of a microchip (© Bobkov Evgeniy/Shutterstock)

Golden Hall in Stockholm City Hall for today's Nobel Prize Award ceremonies (© Mikhail Markovskiy/Shutterstock)

冰岛羊 (© John Porter LRPS/Alamy)

Icelandic sheep for the first night of the Yule Lads (© John Porter LRPS/Alamy)

Bernina Express on the Landwasser Viaduct, Graubünden, Switzerland (© Marco Bottigelli/Getty Images)

Herd of red deer stags in a snow-covered pine forest, Cairngorms National Park (© Scotland: The Big Picture/Minden Pictures)

Luzulo-Fagetum beech forest covered with frost and snow, Ardennes, Belgium (© Philippe Moes/Alamy)

Table Mountain, Cape Town, South Africa (© 4FR/Getty Images)

Temple of Saturn in the Roman Forum, Rome, Italy (© Joe Daniel Price/Getty Images)

Annual Schwäbisch Hall Weihnachtsmarkt in the market square, Baden-Württemberg, Germany (© sack/Getty Images Plus)

Christmas lights in Carnaby Street, London (© Roy James Shakespeare/Getty Images)

Rainbow eucalyptus trees in Maui, Hawaii (© GlowingEarth/Getty Images Plus)

Snowflake (© TothGaborGyula/Getty Images Plus)

The Callanish Stones, Isle of Lewis, at sunset (© Neil MacConnell/Alamy Stock Photo)

Gentoo penguins airing grievances in Antarctica (© Grafissimo/Getty Images)

A herd of reindeer in Norway (© Lena Granefelt/plainpicture)

Christmas decorations in Warsaw, Poland, for Christmas Day (© David Milsen/Alamy)

Rubber duck race for Boxing Day (© Jessica Lynn Culver/Getty Images)

Skating on a frozen canal near the windmills at Kinderdijk in the Netherlands (© Lourens Smak/Alamy)

Trumpeter swans at Kelly Warm Springs, near Kelly, Wyoming, USA (© DEEPOL by plainpicture)

German ski jumper Markus Eisenbichler competing in the Four Hills Tournament, Innsbruck, Austria, on 3 January 2018 (© Daniel Karmann/picture alliance via Getty Images)

Fireworks for New Year's Eve in Backnang, Germany (© Lilly/Alamy)