excerpt from

The Greening of Mars

by James Lovelock and Michael Allaby

1984

edited by Thomas Gangale

from "Travels in Space and Time:"

Mars has a year of 687 days. To be more precise, it is 686.9804 days, which means we have 'leap years' every so often to keep the calendar straight. Our 'leap years' are not like those of Earth, though, which is why I use the expression in quotation marks. On Mars leap years come every fifty-one years, and we lose a day.

We do not count months. On Earth these are based, clumsily, on the orbit of the Moon. Indeed, we have two tiny moons that look about the size Venus looks when seen from Earth. A division of the year into months would force us to choose one in preference to the other, and that would cause endless wrangling among the Phobos and Deimos factions that would spring up instantly. Even then it would not be easy. Phobos orbits Mars three times each day, and Deimos takes rather more than a day to make a single orbit. Martian months would be rather different from terran months! Perhaps we could use both and try to devise a double-month system. I cannot begin to imagine what that would be like.

My date of birth, for the record, was 3.68.06. That is to say, I was born on the third day (which we call Tuesday, as I said) of the sixty-eighth week of the sixth year of the century. We omit the number of the century, but I was born in the year 106.