Undulatus asperatus (or alternately, asperatus) is a cloud formation, proposed in 2009 as a separate cloud classification by the founder of the Cloud Appreciation Society. If successful it will be the first cloud formation added since cirrus intortus in 1951 to the International Cloud Atlas of the World Meteorological Organization. The name translates approximately as “roughened or agitated waves”.

The barren landscapes of the south-western US provided inspiration for photographer David Clapp. He visited Nevada, New Mexico, Utah and Arizona as part of his project on other-worldy locations, with surreal results. Here: An infrared image at dusk of strange clay rock formations in Ah-Shi-Sle-Pah Wilderness in Farmington, New Mexico. (Photo by David Clapp/Barcroft Images)

A British photographer has captured the hilarious expressions pulled by dogs as they go for a run. From popping eyes to lolling tongues, Nick Ridley from Aylesbury in Buckinghamshire has managed to perfectly pause the pooches in time as they pull a host of funny faces in the great outdoors. The 56-year-old uses a fast shutter speed and lies on the ground snapping away as the dogs run towards him in order to get the perfect shot. Here: A Dogue de Bordeaux. (Photo by Nick Ridley Photography/Caters News Agency)

Truffle hunter Carlo Marenda pets his dog Buc as they search for white truffles through the Langhe Countryside in Roddi, near Alba, north-western Italy, on November 8, 2020. Despite new measures to stop the spread of the Covid-19, truffles hunters are allowed to search in the countryside in Italy. (Photo by Marco Bertorello/AFP Photo)

Some wave over the rainbow – a splash of colour is captured in spray over the sea wall at Totland Bay on the Isle of Wight off the south coast of England on February 16, 2022. (Photo by Jamie Russell/Bournemouth News)

A moon bear rests in a pool inside an enclosure at the Vietnam bear rescue centre, in Tam Dao national park, Vinh Phuc, Vietnam, 09 July 2019. The center is operated by international organization Animals Asia. There are currently 184 bears living at the the Vietnam Bear Rescue Centre. It is estimated that there are less than a few hundred bears left in the wild in Vietnam. According to the latest data from the Ministry of Agriculture and Rural development, around 600 bears are still being kept on farms. In Vietnam, Animals Asia has rescued a total of 209 sun bears and moon bears. (Photo by Minh Hoang/EPA/EFE/Rex Features/Shutterstock)

The Christmas Train of Lights on November 27, 2024 on the Dartmouth Steam Railway in Devon, UK, which runs until 30th December 2024, is reflected in the calm water of the River Dart after leaving Kingswear on its return trip to Paignton. The carriages and steam locomotives on the festive service are lit inside and out with coloured lights. (Photo by Graham Hunt/BNPS)