The Meta Olympia world uses the Darian Calendar for time-keeping, the system created by Thomas Gangale and published in 1986.
Meta Olympia is 60 years in the future, that run approximately parallel to real-world time.
A Martian solar day (sol) is 39 minutes 35.244 seconds longer than Terrestrial solar day.
The Martian year is 668.59 sols, which corresponds to 686.86 days on Earth.
The Darian calendar has 24 months. The calendar year begins with Sagittarius and the final month Vrishika.
The first 5 months of each quarter are 28 sols in length and the 6th month only 27 sols .
Sols of a week correspond with the 7 day week. In Meta Olympia, most colonies adhere to a 5 day work week with Saturni and Solis representing the weekend.
Mars has corresponding seasons as a result of the planet's tilt, 25 degrees compared with Earth's 23 degrees.
In addition to the familiar seasons of Spring, Summer, Fall, and Winter, Mars has two additional seasons, Aphelion and Perihelion, due to the highly elliptical orbit compared with the nearly circular orbit of Earth. This brings it much closer to the sun at some times of the year.
During Perihelion, the planet gets 40% more energy from the sun than during Aphelion.