The most likely future for Mars from a human point of view is as a mining colony, supplying us with minerals that have been exhausted on Earth. Thousands of different data about Planet Mars are recorded every day with reference to Earth calendars. It works, but would it not be better to record them on a Martian calendar and timekeeping system? Shouldn’t our engineers and scientists work with clocks that are tailored for the special situation on Planet Mars? They now could see both Earth and Martian times any moment on their clocks in their offices or control rooms.

b

That explains already that we need a different calendar. If we want to express that an event will happen on Mars at a day in the future we say: on Tuesday, April 16 in the year 2003. Using the new Martian calendar we would simply say: on Sol 425 in Orb 3. To avoid any confusion we use different units for days and years: Sols and Orbs. The unit Sol for Martian days has been used already by scientists and astronomers for many decades. The name Orb is an abbreviation for orbit  as the unit for a Martian year. Since there are 668 sols during one complete orbit, it suffices to call the number of the Sol to determine a special day in Orb 3. The use of 12 names for months and seven days of week days doesn’t make sense for the planet Mars since there is no comparable influence of  a large Moon around the red planet.

We subdivide the time of a day on Earth into 24 hours (12 a.m. and 12 p.m.)  with 60 minutes for each hour and 60 seconds for each minute. The time keeping on Earth was developed  5,000 years ago by priests who wanted to establish  when to plant seeds and plan religious ceremonies. Now we want to use a less complex system for Mars: we simply use 100 parts of the Sol’s time and call them Centisols. If we want to describe a precise moment happening on Mars we now say, using the Earth calendar: it will occur on Tuesday,  April 16. in the year 2003 at 4 p.m., 33 minutes and 19 seconds. But this doesn’t tell us anything about the planet Mars. Will there be spring? Will there be daylight or dark night  at that moment?

Using Mars-Time we would say: on Sol 425 in Orb 3 at 35 Centisols. Isn’t that much simpler? Every child that can read numbers from 0 to 100 would know that 35 centisols means a third of a sol's time, comparable to 8 hours.

The simplicity of the Martian calendar  is even more convincing when comparing Mars and Earth timekeeping systems:

Until today we are still marking each document which reaches NASA from Mars (photo, wind velocity or temperature data) only with ERT (Earth Receiving Time). But we can’t understand anything from this information about the situation on Mars when this data was created. Had we already the proposed Martian calendar and clock in use, scientists could find answers from the marked data <425-03-35>  to the many questions such as: What will be the position of Mars on its way through the solar system on Sol 425?  Will it be at a period of heavy dust storms or calm weather ? What season will it be during  orb   03 in the hemisphere where the event will take place? And the data 35 tells the scientist if there will be sun light or nightly darkness at the location. This wealth of information would justify the existence of the proposed Martian calendar and clock.

c

The original presentation of the proposal shows an electronic wrist watch which scientists working on a Martian project could wear. The watch making industry has progressed so much that it is not a problem to produce clocks and even wrist watches with Earth and Martian data. A team of  astronomers, scientists, engineers and programmers would collect the required data and program them into the time pieces.

In the upper left corner we would see the Orb (Martian year) in numbers from 0 to 100. The upper right corner would indicate the Sol from 0 to 668 or 669. Since the accurate number of Sols per Orb is 668.5990, a leap year would be introduced by astronomers as needed when programming the Martian clocks. The left lower corner would show the Sol’s time in Centisols (from 0 to 100). A pressure on the button would show not only the Centisols but in addition also the decimals for more precise time. After pushing a button the right lower corner would indicate the local zonetime.

What else could a scientist wish to see? The message from Earth to Mars and back requires considerable time even if it sailed at the speed of light. It would be practical if a second mode could be selected by pushing a button on the wrist watch. The position of Mars and Earth should be shown on their orbits through the solar system. Automatically the time of the electronic communication could be read in minutes and centisols on the wrist watch's screen.

d

There are so many new units and concepts described that the question appears: why not get rid of the cumbersome 360º longitude and 90º latitude and replace them by 100 Meridians around the equator of Mars? The small size of the red planet would justify this. We also could use the same numbers for space and time on Mars. Since all 100 Meridians would face the sun over the time of 100 Centisols at each rotation of Mars around its axis, the numbers would be identical for location on Mars’ surface and sol’s time. To describe a position on Mars’s surface we would use Mers for meridians from 0 to 100 and Lats for latitude from 0 to 25 from the equator to each pole.  

This means that if a Mars probe has landed near the meridian 21, precisely on 21.843 Mers and 10.169 Lats, a point west of the Mars Zero Meridian on the northern hemisphere, every scientist would know immediately that the sun would be at this location in the zenith at 21.843 centisols time. And if he wished to understand the local situation he would push a button and see the Zone Time.

Since the Mars axis is inclined like the Earth’s axis, there is an effect of seasons on Mars  which will be different for the two hemispheres. Since one orb is almost twice as long as a year and the eccentricity of the Martian orbit is much greater, the length of seasons is not equal. The sols of the seasons are for fall, winter, spring and summer: 194, 178, 143 and 154. Colored dots would indicate on the clock's screen in mode 1 the season on the northern and southern hemispheres.

As soon as these proposals for the simple Martian calendar and clock are accepted by scientists, organizations such as NASA, the International Astronomical Union and other worldwide institutions, scientists or engineers working on Martian projects could easily determine the time on the red planet. Great assistance could be given by members of the Planetary Society, the Mars Society and other institutions interested in space and its future by supporting these novel ideas.

 What can you do? You can express your personal opinion. If you like or dislike this proposal, you may e-mail your comments to Manfred Krutein.

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