• Mars Date/Time:  Year 1, Sur One, Sol 24 (1.1.24)  4:16 PM NST
• Earth Date/Time:  27 January 2016  2:00 PM PST

As we have noted, a calendar is a human device, not a scientific one. This is especially true when it comes to the construction of a week. A day is determined by the time it takes a planet to make one rotation on its axis. A year is determined by the time it takes a planet to make one orbit of the Sun. 

A week = 7 days because our ancestors saw seven significant moving objects in the sky.

However, a week has no astronomical cycle. It is simply a device humans created. A calendar doesn’t have to be divided into weeks; however, over time we have allowed the ‘week’ to define a boundary between work and rest. For this reason alone it would create problems to revise or eliminate the use of the ‘week’ concept in the Mars calendar.

WEEK
Humans have divided the Earth calendar into weeks simply because they knew of seven moving heavenly bodies in the sky. Those seven objects were the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn. The Latin/Spanish names for those objects are Sōlis/domingo, Lūnae/lunes, Martis/martes, Mercuriī/miércoles, Iovis/jueves, Veneris/viernes, Saturnī/sábado. The English version of the days of the week were heavily influenced by the germanic language; however, the names still correspond to the names of the seven moving objects in our sky.

The first month of the Mars year is 60 days long and has 8 1/2 weeks.

A week is simply a repeating pattern of the names of seven objects in Earth sky. If Earth had two Moons, or if Uranus or Neptune were in an orbit close enough to be visible to the naked eye, we might have an eight-day week, instead of seven. 

Despite its simplistic invention, the week is an important part of how humans note time, so ESEP has chosen to keep the same convention for the Mars calendar; however, because a day on Mars is 40 minutes longer, the days of the week are not in sync. On any given day, the days of the week will not usually be the same on Earth and Mars. When it is Friday on Earth, it is probably not Friday on Mars.

Some discussion occurred regarding changing the name of Tuesday (Martis in Latin) to Terra, since Tuesday was named for Earth’s perspective of Mars, and from Mars perspective, Earth would be one of the significant moving objects in the sky. The idea was rejected.