Martian frost is beautiful, as NASA’s images prove, but to future human astronauts on the Red Planet, it might also have a practical use. Beyond hydrating extraterrestrial travelers, water frost could be used for agriculture or as a propellant for spacecraft.

https://www.smithsonianmag.com/smart-news/see-the-chilling-beauty-of-winter-on-mars-180981380/

Thanks Barbara - the pictures are beautiful - especially the pits at the South Pole. They look like jewellery designs or pendants.
Awesome!