Timekeeping on Mars

Timekeeping on Mars is a bit difficult because the planet has a much longer day than Earth does. A day on Earth is 24 hours, but a day on Mars is 24 hours and 39 minutes. To help us keep track of time on Mars, we use something called a Martian day. Martian days are measured from one sunrise to the next sunrise on Mars. So, one Martian day is a little bit longer than one day here on Earth.