Stromatolites, one of the most ancient life forms on earth, mats of micro-organisms that become rock-like structures through accretion of calcium carbonate, in highly saline lagoons like here in Lake Thetis, Cervantes, Dandaragan Shire, Western Australia, Australia, Pacific

Stromatolites, one of the most ancient life forms on earth, mats of micro-organisms that become rock-like structures through accretion of calcium carbonate, in highly saline lagoons like here in Lake Thetis, Cervantes, Dandaragan Shire, Western Australia, Australia, Pacific

Walkers on the Helvellyn Range in winter conditions, Lake District, UK.

Walkers on Helvellyn summit in winter conditions, Lake District, UK.

Looking across hoare frosted grass on the Helvellyn Range, Lake District, UK.

Ice feathers formed during a hard frost, when temperatures fell below minus 10 during the December 2010 cold snap, Ambleside, Cumbria, England, United Kingdom, Europe

Ice feathers formed during a hard frost, when temperatures fell below minus 10 during the December 2010 cold snap, Ambleside, Cumbria, England, United Kingdom, Europe

Formation of Rocky Planets, Illustration