How long is a day on Mars?
A day on Mars, called a sol, lasts about 24 hours and 37 minutes, only slightly longer than a day on Earth. A Martian year lasts about 687 Earth days.
Mars spins on its axis at a speed very similar to Earth's, so days and nights there would feel familiar. Mission teams working with rovers live on Mars time for a while, shifting their schedules by about 40 minutes each day.
Mars is tilted about 25 degrees, close to Earth's 23.4 degrees, so it has seasons too. Because its year is almost twice as long as Earth's, each season lasts roughly twice as long.
Other planets' days
Days vary widely across the solar system. Jupiter spins in under 10 hours, the fastest of any planet. Venus is the slowest: one rotation takes about 243 Earth days, longer than its year.
The difference between Martian and Earth days means mission clocks drift. Engineers on early rover missions wore special watches that ran slightly slow so they could keep track of Mars time.
Did You Know?
The word sol comes from the Latin word for Sun. NASA started using it for Martian days during the Viking missions in the 1970s.