“Water frost has been spotted atop Mars’ gargantuan equatorial volcanoes for the first time — defying previous beliefs that the presence of water there was impossible.

Scientists spotted a hair-thin dusting of frost atop the peaks of the volcanoes in the Tharsis region of the Red Planet — the largest mountains in the solar system, which tower up to three times the height of Mount Everest. In colder months, the frost could consist of up to 150,000 tons of water, or the equivalent of 60 Olympic swimming pools.”

From Live Science.