Time is tricky, and it’s only gonna get worse when we become a multi-planet species. Fortunately, [Folkert van Heusden] has a clock ready for what may be our second home with the Mars Clock. This simple build shows the current time on Mars, using the Martian calendar that NASA uses for their planetary probes.
This calendar, called Mars 24, was designed by [Michael Allison] of NASA back in 1998, and is used by the current batch of Martian probes. You can’t just use an Earth clock on Mars because a Martian day is 24 hours and 39 minutes. Instead, [Michael] created a new calendar based on the rotation and orbit of Mars that also allows you to calculate sunrise and sunsets, which is vital for a probe that uses solar power. It is based on the same breakdown of time, with 24 hours, 60 minutes and 60 seconds, but each of these is slightly longer than the Earth equivalent.
[Folkert] tool the example formulas that NASA themselves provide for calculating Mars 24 time, and wrote an Arduino program that converts Earth to Mars 24 time. This then drives an LED ring that indicates the hour in (appropriately enough) red, the minute in green and the second in blue. This is then mounted on a wooden plate and case that he created with Makercase, a neat site that creates plans for wood laser-cut cases.
It’s a neat, simple build overall, although I would like to see one addition: a switch to go between Earth and Mars time. And perhaps a heat ray attachment that will assist the inevitable victory of our new Martian overlords.