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 of four, we know dry-ice snowflakes would be cube-shaped,” 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.
At the end of winter, the season’s buildup of ice can thaw and turn into gas, creating unique shapes that have reminded NASA scientists of Swiss cheese, Dalmatian spots, fried eggs, spiders and other unusual formations.
During winter in Jezero Crater, recent high temperatures have been about -13 degrees C, with lows of about -84 degrees.
Meanwhile, at Gale Crater in the Southern Hemisphere near the Martian equator, the Curiosity rover, which landed on Mars in 2012, has been experiencing highs of -15 and lows of -76.
Seasons on Mars tend to last longer because the planet’s oval-shaped orbit around the sun means that a single Martian year is 687 days, or nearly two Earth years.
NASA scientists celebrated the Mars new year on December 26, which coincided with the arrival of the spring equinox in the Northern Hemisphere.
“Scientists count Mars years starting from the planet’s northern spring equinox that occurred in 1955 — an arbitrary point to begin, but it’s useful to have a system,” according to a post on the NASA Mars Facebook page.
“Numbering Mars years helps scientists keep track of long term observations, like weather data collected by NASA spacecraft over the decades.”