The landing of the fourth robot on Mars was celebrated ten years ago.

The mission of the rover was to determine if the red planet could have supported life.

The robot is small and has instruments used to study the planet's climate and geology. How did the mission end? What can the future of space exploration teach us?

Dr. Vasavada said that the mission was a huge success.

He said that it was possible for it to be habitable for millions of years.

The ability of the rover to detect signs of life wasn't necessarily a sign that Mars was alive. Vasavada wanted to find out if life was possible there.

He said that there are no big life forms on Mars. "So if life ever did take hold, it probably never got past the first stage of colonization."

A sharp change

What kind of life was there on the red planet? Is it possible that there was an event that made it impossible to live in?

Vasavada believes it's a combination of events.

Evidence shows that rivers once coursed along the surface and that an ocean once existed. He said that Mars was a lot more Earth-like than it is today.

The development of life may have been affected by the size of the planet.

The smaller planet allowed it to cool faster. He said that it lost its ability to generate a magnetic field once it cooled. The atmosphere was stripped away by the radiation in space. It couldn't stay warm and have liquid water because of that.

The planet became cold and inhospitable as a result.

A unique landing point

The spot that the rover initially descended on provided new insights for the team working to understand Mars.

There is a crater called the Gale Crater. The impact crater was formed when a rock hit the planet. There were layers of mud that built up on the sides of a mountain after it was filled with water.

Vasavada said that this meant that they could land there and see if the silt was deposited in lakes and streams. We could read the early history of Mars by driving up the rock layers and finding out if any of the periods had good weather.

The scientist was surprised by the success of the mission.

"For the most part, every layer we've looked at formed in a wet environment and had conditions that would have been favorable to life."

The story was adapted for the internet.