Have you ever wondered about what winter is like on the surface of Mars? Is there snow? And if there is, how much of it is there?
Have you ever wondered about what winter is like on Mars? NASA has a series of photographs taken from orbit that show the Martian winter wonderland. Frozen landscapes with cube-shaped snow are just one of the characteristics of a Martian winter. The coldest temperature on the red planet is around Mars’ poles, where it can get as freezing as minus 123 degrees Celsius. But despite the extreme cold, Mars doesn’t get as much snow as Earth does. In fact, according to NASA, each Martian year (a Martian year equals two Earth years) has no more than a few centimeters of snow. Furthermore, most of this snow falls on flat surfaces, making it difficult to accumulate. But even though there isn’t abundant snow on Mars, winter on the red planet is magical and offers a play of colors.
Winter on Mars: Two types of snow
On Mars, we can find two forms of snow. Mars has snow in the form of water ice and carbon dioxide, also known as dry ice. And because there are two types of snow on Mars, little of it accumulates. This is because the air on Mars is very thin compared to air on Earth. Since the air is thin and temperatures so cold, water-ice snow turns into a gas long before it lands on the surface. Dry ice on the other hand does make it to the Martian surface. But even though there isn’t much of it, some dry ice accumulates. Sylvain Piqueux, a NASA scientist explains that there’s is enough of it for someone to snowshoe across it. Snow accumulates more on craters or cliffsides thanks to the sloped surface.
How do we know there is snow on Mars?
Despite the fact that we have never actually photographed snow falling on Mars, we know it exists thanks to a few instruments on the orbiters circling the red planet. For example, the Mars Reconnaissance Orbiter can peer through cloud cover on Mars thanks to the so-called Mars Climate Sounder Instrument. It detects light in wavelengths the human eye cannot. This allows experts to spot carbon dioxide snowing on the surface. Back in 2008, NASA used the Phoenix lander to spot water-ice snow falling on Mars. The Phoenix lander was sent some 1,600 kilometers from Mars’ North Pole.