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Mars may seem like a dry, desolate place, but the red planet transforms into an otherworldly wonderland in winter, according to a new video shared by NASA.

It’s late winter in Mars’ Northern Hemisphere, where the Perseverance rover and Ingenuity helicopter are exploring an ancient river delta (三角洲) that once fed into Jezero Crater billions of years ago.

As the planet’s main feature, dust drives Martian weather, but the planet is no stranger to snow, ice and frost. There are two types of snow on Mars. One is the kind we experience on Earth made of frozen water. The thin Martian air and sub-zero temperatures means that traditional snow changes from a solid directly to a gas, before touching the ground on Mars.

The other type of Martian snow is carbon dioxide based, or dry ice, and it can land on the surface. A few feet of snow tends to fall on Mars in its flat regions near the poles. “Enough falls that you could snowshoe (穿雪鞋走路) across it.” said Sylvain Piqueux, a Mars scientist at NASA’S Jet Propulsion Laboratory in Pasadena, California, in a statement.

So far, no orbiters(轨道飞行器) or rovers have been able to see snow fall on the red planet because the weather phenomenon only occurs at the poles beneath cloud cover at night. The cameras on the orbiters can’t peer through the clouds, and no robotic explorers have been developed that could survive the freezing temperatures at the poles, which can be as low as minus 120 degrees Celsius.

However, the Mars Climate Sounder instrument on the Mars Reconnaissance Orbiter can detect light that’s invisible to the human eye. It has made detections of carbon dioxide snow falling at the Martian poles. The Phoenix lander, which arrived on Mars in 2008, also used one of its laser instruments to detect water-ice snow from its spot about 1,600 kilometers away from the Martian north pole.

Thanks to photographers, we know snowflakes on Earth are unique and six sided. Beneath a microscope, Martian snowflakes would likely look a little different. “Because carbon dioxide ice has a symmetry (对称) of four, we know dry-ice snowflakes would be cube-shaped (立方体的), ” Piqueux said. “Thanks to the Mars Climate Sounder, we can tell these snowflakes would be smaller than the width of a human hair.”

Ice and carbon dioxide-based frosts also form on Mars, and they can occur farther away from the poles. The Odyssey orbiter (which entered Mars orbit in 2001) has watched frost forming and turning to a gas in the sunlight, while the Viking landers spotted icy frost on Mars when they arrived in the 1970s.