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Mars has an eccentricity higher than most of the other planets in the solar system, and has an average distance from the Sun of roughly 230 million km (1.5 AU). Its orbital period is 687 (Earth) days, but the solar day (or sol) on Mars is only slightly more than an Earth day: 24 hours, 39 minutes, and 35.244 seconds. See Timekeeping on Mars.
Approximately every 780 days opposition occurs, which is when Mars is nearest to Earth. This minimum distance varies between about 55 and 100 million km due to the planets' elliptical orbits. [27] The next Mars opposition will occur on December 24, 2007.
On August 27, 2003, at 9:51:13 UT, Mars made its closest approach to Earth in nearly 60,000 years: 55,758,006 km (approximately 35 million miles) without Light-time correction. This occurred when Mars was one day from opposition and about three days from its perihelion, making Mars particularly easy to see from Earth. The last time it came so close is estimated to have been on September 12, 57,617 BC. Detailed analysis of the solar system's gravitational landscape forecasts an even closer approach in 2287. However, this record approach was only very slightly closer than other recent close approaches. For instance, the minimum distance on August 22, 1924 was 0.37284 AU, compared to 0.37271 AU on August 27, 2003, and the minimum distance on August 24, 2208 will be 0.37278 AU.[28]