Although it’s found on another planet altogether, there’s a permanent "winter wonderland" on Mars that would never suffer a green Christmas — or a red one, as the case may be. The European Space Agency’s Mars Express orbiter used its High Resolution Stereo Camera (HRSC) to take pictures of the 82 kilometer (51 mile)-wide Korolev crater near Mars’ north pole, home to a massive mound made of water ice that persists year-round due to the crater’s peculiar topography.

Korolev crater’s ice sheet is 1.8 kilometers (1.1 miles) deep, and with a volume of 2,200 cubic kilometers (530 cubic miles), the ice pack holds a similar amount of water in ice form as Canada’s Great Bear Lake, or five times that of Lake Erie.
During the summer season, the ice packs at Mars’ poles shrink as the region warms up, but the ice in Korolev crater is preserved by a phenomenon known as a ‘cold trap’: the air flowing over the bottom of the crater is cooled by the ice sheet, causing it to sink and create a cold layer of air that sits above the ice, shielding it from the layers of air above the crater, even as things warm up during the summer — preserving this "Winter wonderland" on Mars, year ’round.

From all of us here at Unknown Country, we’d like to wish everyone Happy Holidays, and a wonderful 2019!