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Color illustration showing the sun in the sky for a Martian year.
This artist's illustration shows how the Sun would have looked from Carl Sagan Memorial Station at a specific time each month on Mars over the course of a Martian year. (Credit: Dennis Mammana)
 

What's a Martian Year?

A Martian year is the amount of time it takes for Mars to make one complete orbit around the Sun - 687 Earth days. It takes Earth about 365 - Earth days to complete its annual journey around the Sun. The reason it takes Mars longer is that it is farther from the Sun and travels more slowly.

And why are we using Earth days as a measurement? Each planet spins on its axis at a different rate. So a day (sunrise to sunrise or sunset to sunset) on each planet is different.

Join NASA on a cosmic road trip across our vast Solar System - all from the comfort of Earth!

NASA spacecraft will be heading for key locations during the Year of the Solar System from October 2010 until August 2012 - a Martian year that encapsulates almost two Earth years of exciting mission events!

These 23 months of exploration by robotic tourists will reveal the familiar objects of our solar system as new worlds through new discoveries. Discover these worlds for yourself through activities highlighting a new topic each month. You can also submit photographs, artwork, music, or words of your YSS experiences to our Share Your Stories page.

For more information about planets, dwarf planets, asteroids, and other cool things in our solar system visit our planet pages.

The Year of the Solar System is supported by NASA's Science Mission Directorate and its Planetary Science Division.


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YSS Website Usability: http://www.surveymonkey.com/s/YSS_Website_Usability_Survey_A
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Last Updated: 11 Apr 2011