It's taken roughly five months, but a massive iceberg has separated from Antarctica's Pine Island Glacier. According to NASA's Earth Observatory, the estimated size of this iceberg, named B-31, is around 660 square kilometres (33 km long by 20 km wide) – a city-sized block of ice that has slowly migrated away from the continent, and is now floating out to sea. Take a look at some massive icebergs afloat in the oceans. Photo: File photo of an iceberg floating near a harbour in the town of Kulusuk, east Greenland August 1, 2009. (Photo by Bob Strong/Reuters)

A photographer has done her best to guess what her dog is daydreaming about – creating a series of fantasy adventures around her unaware pooch as he takes his daily naps. (Photo by Caters News)

Michael O’Neill won a prize in animal portraits with fry of a peacock bass hovering around their mother for protection against predators in South Florida. (Photo by Michael Patrick O'Neill/2016 National Geographic Nature Photographer of the Year)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

An incredible clear-air lightning display from storms to the east of Noonamah, just outside Darwin on April 6, 2015. (Photo by Jacci Ingham/The Guardian)

Wildlife photographer Danté Fenolio has headed into areas untouched by sunlight – deep seas, caves and underground – and found creatures that are exploding with colour. Here: The golden harlequin toad has vanished from the wild, and only a small number live on in captivity. A fungus caused them, and many other amphibians, to die out in their home in Central America. (Photo by Danté Fenolio/The Guardian/Johns Hopkins University Press)

The German Society for Nature Photography (GDT) has selected its Nature Photographer of the Year 2020. Here: Winner, Other animals. Jens Cullmann – Danger in the Mud. Crocodile in a drying pool. (Photo by Jens Cullmann/2020 GDT Nature Photographer of the Year)

A cave diver in Anhumas Abyss, Bonito, Brazil. (Photo by Marcio Cabral/Epson International Pano Awards 2018)