Mars24 Sunclock — Time on Mars

Screenshot of sample Mars24 v. 7.1 display

The Mars24 software displays a Mars sunclock, a graphical representation of the planet Mars showing its current sun- and nightsides, along with a numerical readout of the "standard" Mars time as well lander and other local times. Other displays include a plot showing the relative orbital positions of Mars and Earth and a diagram showing the solar angle and path for a given location on Mars.

Mars24 is a cross-platform application that runs on Macintosh, Windows, Linux and other desktop computers.

The current version of Mars24 is 8.0.1 released 2019-02-13.

Get Mars24

Mars24 requires a computer with a Java 8 (or better) runtime environment installed.

Documentation and Credits

Other information available here includes:

Also on the GISS website is a 1998 science brief titled "Telling Time on Mars".


If you wish to be notified when new versions of Mars24 are released or if you would like to report a bug, please contact Dr. Robert B. Schmunk.

If you have technical questions about the definition of Mars Solar Time and the mathematical algorithm adopted for its calculation by Mars24, please contact Dr. Michael Allison.