NASA, the American space agency, had placed a rover called Opportunity on the surface of Mars. The rover has discovered a rock, called Esperance, that has caused a lot of excitement. The detective work scientists did on the rock’s composition points towards the rock having been in flowing water sometime in its past. Scientists keep looking for evidence of water on other planets. This is because most of them believe water is needed to have life on a planet.
Opportunity (see image) and its twin rover Spirit were sent to Mars to roam around and explore. They landed on Mars in 2004, and were on a 3 month mission. Nine years later, Opportunity is still making discoveries and roaming around on the planet. It has travelled a distance of over 22 miles (36 km) on Mars. Some of its parts are not operating as well now. It drives backwards because of some issues with one of its wheels. Scientists are not sure how much longer Opportunity will give us the opportunity to study rocks on Mars. Spirit stopped working in 2010.
Opportunity has a much younger and more hi-tech friend also roaming around on Mars investigating rocks. The rover Curiosity has been on Mars since last year.
Here are a couple of videos about Mars.
Image Credits: http://marsrovers.jpl.nasa.gov for Esperance rock’s and Opportunity’s images