Why Mars Lacks A Standard Calendar

Mars does not have an official calendar, so scientists track time by counting orbital degrees. They start the Martian year from a specific equinox that took place in 1955.

Because a Martian year lasts nearly two Earth years, standard calendars are practically useless there. Astronomers have instead adopted a system based on the planet's position in its orbit around the sun. By anchoring their timeline to the 1955 equinox, researchers can keep consistent records for robotic missions. It is a strange way to measure time, but essential for planning long-term exploration.