If humans colonised Mars, how would they calculate time, as a Martian day is longer than one on Earth? (continued)
Simon Dales
Oxford, UK
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The Martian day is only about 40 minutes longer than the terrestrial one, so astronauts’ body clocks should be happy, but their watches would drift from the local day.
History tells us that they should always use one measure, lest they get confused. In the UK, we used to have Bristol time and London time. That was fine until we wanted railway timetables.
Pope Gregory XIII’s astronomers invented a better calendar to replace the Roman Julian one, so the Catholic world adopted it. England was strongly Protestant at the time, so resisted this “Papist plot”. Over many decades, the two calendars drifted.
Confusing units like feet and metres can have dire consequences. Do that and spacecraft go splat, so day length becomes moot.
Charles Joynson
Rayleigh, Essex, UK
I researched this question during the writing of my book and found that Robert Zubrin, the founder and president of the Mars Society, has that time on Mars could be measured in the same way that it is on Earth.
This would mean dividing a Martian day into 24 hours, each with 60 minutes. However, the seconds on Mars would be just a fraction longer than seconds on Earth.
Zubrin says we just need to divide each Martian day by 24 to get a Martian hour, and each Martian hour by 60 to get a Martian minute, and then divide that by 60 to get a Martian second. This would be equivalent to 1.0275 Earth seconds, which is a small enough difference not to be noticeable. Thus, 1 hour on Earth and Mars would equate to 15 angular degrees of surface rotational longitude, 1 minute would be 15 angular minutes of longitude and 1 second 15 angular seconds of longitude.
Additionally, Zubrin says that Martian seasons could be divided up into equal angles of travel around the sun, so each of the 12 months would represent 30 degrees of orbital travel. It may be confusing to use names from Earth. Signs of the zodiac may be a more acceptable alternative.
Harold Fuchs
London, UK
What makes you think humans would have a say in how Martians’ clocks or calendars work?
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