Mars is the fourth planet from the Sun and the seventh largest in the Solar System. A cold, dusty desert world with a thin atmosphere (mostly CO₂), the planet features extinct volcanoes, deep canyons, polar ice caps, and seasons. Mars has two small moons (Phobos and Deimos), a day just over 24 hours long, and a year lasting about 687 Earth days. It is a prime focus of robotic exploration and studies about past water and habitability.
Source: science.nasa.gov
25/01/2012

Where on Mars should you spend the winter? As winter approached in the southern hemisphere of Mars last November, the Opportunity rover had just this problem -- it needed a place to go. The reduced amount of sunlight impacting Opportunity's solar panels combined with the extra power needed to keep equipment warm could drain Opportunity's batteries. Therefore Opportunity was instructed to climb onto the 15 degree incline of Greeley's Haven, shown as the rocky slope ahead. The incline increased power input as Opportunity's solar panels now have greater exposure to sunlight, while also giving the rolling robot some interesting landscape to explore. Visible in the distance, beyond Greeley Haven, lies expansive Endeavour Crater, the ancient impact basin that Opportunity will continue exploring as the Martian winter concludes in a few months, if it survives.