The planet Mars has remained the most intriguing planet in our solar system. It has always held out the possibility of past or present life. Biological life requires certain elements. To positively determine if life ever had or possible still did exist there, probes would have to be sent to land on its surface and make detailed photographic and chemical analysis of the soil and rocks. 

The first mechanical visitors to the red planet were the two Viking landers launched by the United States in the mid-1970s.  The tremendous distance from the Earth to Mars will prove the biggest obstacle to sending crews there to explore. Advance propulsion systems must be developed to make the time traveling to Mars within human endurance.  Robotic probes do not suffer this problem and the United States began working on the first micro-rover to be sent to Mars.  That mission was Mars Pathfinder, and included the small rover Sojourner.  This mission launched a new and very successful era of rover exploration of the planet Mars.

The Mars Exploration Rovers Spirit and Opportunity were even more sophisticated and long-lived and have returned proof of previous presence of water on the planet's surface.  The next rover to land on Mars will be the Mars Science Laboratory, which will further our knowledge of the planet and its history.

The United States in not exploring Mars along. The European Space Agency has launched successful probes to circle the planet and record its surface features in unprecedented detail. The ESA will follow in the years ahead with its ExoMars rover, to explore a yet to be determined area of the planet. This is the gold age of Mars exploration. You can click on the links to the left to learn more about these programs.