Mare Chronium -- A Brief History of Martian Time

April 23, 2010 3:49 AM

Martian clocks and calendars have been discussed in the writings of various authors over the past one hundred years. This article recounts the history of Martian timekeeping from 1880 to 1998.
posted by vostok (10 comments total)

I just finished Red Mars, which had this system:

And then it was ringing midnight, and they were in the Martian time slip [the author's bow to Philip K. Dick's novel], the thirty-nine-and-a half-minute gap between 12:00:00 and 12:00:01; when all the clocks went blank or stopped moving.

I was immediately captivated by this idea and have been thinking about it ever since. I even briefly wondered what other systems there were, so this post is a welcome and unlikely coincidence. Thanks!
posted by DU at 4:35 AM on April 23, 2010 [2 favorites]

This is an incredible treasure trove of information. Thank you for posting it.

DU, Robinson's calendar system is mentioned on this page. I loved the timeslip idea, too. That's one of my favorite series.
posted by zarq at 4:50 AM on April 23, 2010

from the link: "There would be absolute chaos on Mars if one tried to reckon time by the 24-hour terrestrial solar day. Suppose that on a given date and at a specified point on Mars, local midnight coincides with Greenwich Mean Time midnight (00:00 GMT, in terms of 24-hour time). On that sol the Sun rises at about 06:10 and sets around 18:30. The following local midnight does not occur until nearly 40 minutes into the next GMT day, and after another sol passes the Martian sky lags the terrestrial clock by 79 minutes. Now, try to imagine the situation a couple of weeks later when a Martian executive opens her office in the middle of the night just because it is nine o'clock in the morning in Greenwich. Still another week later a young Martian is told he cannot play outside because "it's too dark outside this afternoon and it won't be dawn until past your bedtime". If you can't imagine having to live like this then don't think the Martians will stand for it either. They will have to live by the Martian solar day, not the terrestrial solar day."

Right, right. Because the real reason young Johnny cannot go outside and play on Mars is because of the difference in the length of day, not, say, that he would suffocate and boil alive in the Martian atmosphere...
posted by eustacescrubb at 6:13 AM on April 23, 2010

Some of the members of the Spirit and Opportunity rover teams at JPL have lived on a Martian calendar for long periods of time, getting up in the morning when the rovers do, and planning vacations around the Martian winter when the rovers have been largely dormant.

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posted by General Tonic at 6:52 AM on April 23, 2010

Oh yeah, I remember that from a NOVA thing I saw a few years ago. They go to bed 40 minutes later every day. That's gotta screw up the ol' home life.
posted by DU at 7:09 AM on April 23, 2010

The slow seasons and cold weather means appropriation of time.
posted by Mblue at 7:09 AM on April 23, 2010

Good god Metafilter you've been delivering like crazy these past few days.

Great post, thanks!
posted by six-or-six-thirty at 7:57 AM on April 23, 2010

Regarding how the space missions are run, they in fact have changed the length of a second on Mars so that Mars time runs on a 24 hour clock like Earth time.

The timeslip idea is great, but it only works if you do nothing at all constructive during that time -- and that pisses off engineers to no end.
posted by spaceviking at 8:42 AM on April 23, 2010

I already go to bed 40 minutes later every day. I use NASA's Mars24 Sunclock from http://www.giss.nasa.gov/tools/mars24/ just to keep track of my bedtime.
posted by DataPacRat at 9:00 AM on April 23, 2010 [2 favorites]

The timeslip idea is a perfectly reasonable way to adapt the nearly but not quite normal Martian day to completely normal hours, minutes, and seconds. Having the clocks stop displaying the time though is a purely literary device homage a PKD which would not actually be done, as that basically means you have no clock -- even for determining how far you are through the timeslip -- during the timeslip. What any reasonable engineer or programmer would do is have the clock display the time in the timeslip with some indication such as the display blinking or an extra indicator or maybe in a different color to indicate that this is the not-hour that won't have 60 minutes.

(Personally, I'd have the display blink and count down instead of up reaching 0:00 at the end of the timeslip.)
posted by localroger at 4:27 PM on April 23, 2010 [1 favorite]