Spring frost on Mars: Check out this image by NASA's HiRISE camera

Mars, our celestial neighbour, is considered a cold world compared to our Earth and it also has a thin atmosphere. The mean temperature on Mars is around minus 85 degrees Fahrenheit (minus 65 degrees Celsius) while that on Earth is 59 degrees Fahrenheit (15 degrees Celsius).

When the winter season arrives on the Red Planet, it comes with a blanket of carbon dioxide snow. During the spring thaw, this snow evaporates into the atmosphere, lingering longest in the shallow depressions such as the troughs of polygon-patterned ground.

The above image shows the carbon dioxide snow as bluish-white patches among areas of rusty red bare ground. It was captured in 2008 by HiRISE, a camera aboard NASA's Mars Reconnaissance Orbiter (MRO), as a possible landing site for the Phoenix Lander that arrived on Mars later that same year.

HiPOD: Spring Frost on a Cold WorldEnhanced color shows the carbon dioxide snow as bluish-white patches among areas of rusty red bare ground. https://t.co/Biuef890I2NASA/JPL-Caltech/UArizona#Mars #science #NASA pic.twitter.com/e0bs35FvAu

— HiRISE: Beautiful Mars (NASA) (@HiRISE) November 25, 2023

HiRISE, short for the High Resolution Imaging Science Experiment, is operated by the University of Arizona. Launched in 2005, it is one of the most powerful cameras ever sent to another planet, with its images showing extraordinary detail in all kinds of Martian surface features.

The HiRISE camera has been imaging the Red Planet since its arrival at the planet in 2006. In addition to helping scientists explore the surface features as small as a kitchen table in unprecedented detail, it serves as an indispensable tool for helping to select landing sites for robotic and future human exploration.