SAVANNAH, Ga (WSAV) — The Curiosity Rover captures pictures of the Martian skyline and atmosphere every day. However in late May, Curiosity captured rare clouds in the sky using its in color Mast camera. These types of clouds don’t occur that often in the very thin and dry atmosphere. Most clouds are typically found at the Planet’s equator when Mar is farthest from the Sun.
Two Earth years ago, NASA scientists noticed clouds forming earlier than expected. They made sure Curiosity would be set up to start documenting these rare clouds as soon as they appeared in January. The Rover captured images of wispy clouds of ice crystals.
What Makes These Clouds Rare
Most Martian clouds are no higher than about 37 miles in the sky and are made of water ice. These rare clouds are at higher altitudes, at colder temperatures, and are most likely made of frozen carbon dioxide.
The Curiosity team was able to pin point the height of the rare clouds by following the position of the sun in the sky and the color of the “Noctilucent” clouds. The high level clouds glowed brighter as the sun was high in the sky. As the sun began to drop below their altitude, the ice crystals would darken. This is one useful way they can determine how high the clouds are.
Another cool discovery NASA found by looking at these rare clouds is that they have a pastel shimmer to them when the sun is at certain positions. These are called “Mother of Pearl” clouds. They tend to have a light colorful shimmer like a pearl would have. The shimmer comes from the cloud particles growing at the same rate and growing to the same size.
Martian Clouds Unravel a Mystery
NASA scientists were able to solve the mystery of what is creating a long stream of thin clouds coming from a now-existent volcano. Arsia Mons is south of the Martian equator. These mysterious clouds formed seasonally during spring and summer morning due to the combination of orographic lift of the existent volcano’s height (12 miles tall) and meteorological conditions.
For comparison, Mount Everest is only about 5 1/2 miles tall. The spring and summer morning weather conditions plus the height also explains why the clouds would dissipate by midday. Much like how morning fog can form here on Earth but clear by midday.
The flowing cloud formation can stretch as long as 1,100 miles and around 93 miles wide. The Mars Express Visual Monitoring Camera caught the formation on the Red Planet. The images from the camera showed the clouds forming every spring and summer morning.