Phoenix Study Finds 87% of 19 Workers Synced to 24.65-Hour Mars Day
Updated
Updated · spacedaily.com · Jul 31
Phoenix Study Finds 87% of 19 Workers Synced to 24.65-Hour Mars Day
2 articles · Updated · spacedaily.com · Jul 31
Summary
A 2008 Phoenix Mars Lander field study found 87% of 19 monitored mission workers showed circadian timing consistent with synchronizing to Mars’s 24-hour, 39-minute sol during 78 days of operations.
The schedule was used because rover and lander teams need roughly 12 hours to turn one Martian day’s downlink into a safe command load for the next, so staff shifted about 40 minutes later each day to stay aligned with local daylight on Mars.
Sleep and performance still suffered when alignment failed: main sleep averaged 5.98 hours when workers were synchronized, versus 4.91 hours when misaligned, and staying awake at least 21 hours was linked to worse alertness.
NASA treated that risk with fatigue education and timed short-wavelength light exposure after earlier Mars-time missions reported exhaustion-related incidents, including Pathfinder staff abandoning the schedule after about a month.
Full Mars time is now typically limited to early mission checkout—Perseverance planned it for the first 90 sols—because longer missions shift to more sustainable Earth-based operations even if humans can temporarily adapt.