Sidereal Rotation Period of Mars
| Value | 88,642.44 s |
| Status | Conventional / typical value |
| Source | NASA NSSDC Planetary Fact Sheet, Mars (sidereal rotation period, 24.6229 h) |
| Categories | Astronomicalsolar-systemplanets |
| Planck time | 1.6441918e+48 tP |
| attosecond | 8.8642440e+22 as |
| femtosecond | 8.8642440e+19 fs |
| picosecond | 8.8642440e+16 ps |
| nanosecond | 88,642,440,000,000 ns |
| shake | 8,864,244,000,000 shake |
| microsecond | 88,642,440,000 μs |
| millisecond | 88,642,440 ms |
| second | 88,642.44 s |
| minute | 1,477.374 min |
| hour | 24.6229 h |
| sidereal day | 1.0287631 sd |
| day | 1.0259542 d |
| week | 0.14656488 wk |
| fortnight | 0.07328244 fn |
| month | 0.033707605 mo |
| year | 0.0028089094 yr |
| decade | 0.00028089094 dec |
| century | 0.000028089094 cent |
| millennium | 0.0000028089094 mil |
| megayear | 2.8089094e-09 Myr |
| eon | 2.8089094e-12 eon |
Learning zone
Mars turns once in 24 hours 37 minutes — a coincidence, not a consequence, since nothing ties the two planets' spins together, but a lucky one for exploration. The Martian solar day, or sol, runs 24 h 39 m 35 s, close enough to Earth's that surface missions simply live on Mars time: rover operations teams famously wore watches running 2.75 per cent slow, sliding 40 minutes around the terrestrial clock each day until the drift wore the humans out.
The rotation was pinned down centuries before anyone could visit. Huygens sketched the dark wedge of Syrtis Major in 1659 and timed its return to deduce a day of about 24 hours; Herschel refined it to within two minutes by 1781. Today the period is tracked to milliseconds by radio ranging to landers, precisely enough to watch it vary with the seasons as carbon dioxide shifts between the atmosphere and the polar caps.