Jet lag is worse on Mars

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

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"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs." --San Antonio Express-News

Research and actual experience has found that adjusting to the slightly longer Martian day is not as easy as you would think.

If you’re on Mars, or at least work by a Mars clock, you have to figure out how to put up with the exhausting challenge of those extra 40 minutes. To be exact, the Martian day is 24 hours, 39 minutes, and 35 seconds long, a length of day that doesn’t coincide with the human body’s natural rhythms. Scientists, Mars rover drivers, and everyone else in the space community call the Martian day a “sol” to differentiate it from an Earth day. While it doesn’t seem like a big difference, that extra time adds up pretty quickly. It’s like heading west by two time zones every three days. Call it “rocket lag.”


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  • wodun

    Not sure it will matter much as people will be indoors.

  • wodun

    Also, didn’t have to reload the blog today to see the most recent post. Will try later on the tablet.

  • mpthompson

    Seems to me the problem is living under Earth time and trying to stay synchronized with Martian time. If you were on Mars would the body even notice 40 minutes after some acclamation? Studies done in caves where the test subjects were completely cut off from all external time queues found that the subjects naturally adopted about an 18 hour day after a number of weeks — hazily recalled from a National Geographic article I read more than 20 years ago. That’s a much bigger natural drift from the 40 minute difference of the Mars sol.

  • The article went into great detail about more recent research that found people really do prefer a 24 hour day. Read the article at the link.

  • D.K. Williams

    Research by Michel Siffre, living underground for several months in a Texas cave, indicated that without time cues, our circadian rhythm resets to a 25 hour day, not 18. Thus, an extra 40 minutes should not be a problem. In your own life, you may have noticed jet lag being easier flying east to west and harder going west to east. I haven’t seen data on sports teams flying east for games, but I’d bet it’s worse than the other way around. How else can one explain Southern Cal getting pushed around by a bad Boston College football team last season in Beantown?

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