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Ancient Martian Conditions Could Have Supported Life
1. The American space agency recently reported that the planet Mars once could have supported micro-organisms, extremely small life forms. The announcement came after the agency’s Curiosity rover examined a rock on Mars. It was the first sample of rock powder ever collected and tested on the red planet. Curiosity used a drill on its two-meter long robotic arms to cut into the rock and collect about ten grams of powder. Space agency officials called the drilling, the biggest success for the Curiosity team since the rover landed on Mars in August, 2012.
2. After the drilling was done and the powder collected, the small laboratory on Curiosity began a series of tests. American scientists said the test results led them to believe there was once life on Mars. The rock sample came from an area on Mars called Yellowknife Bay. The area had some of the chemicals required to support life as we know it. They include oxygen, hydrogen, nitrogen and carbon. Scientists believe Mars was once a warmer, wetter environment before turning into a freezing dry desert. Researchers say the Martian bedrock showed evidence of many periods of wet conditions. And they say there are clay minerals in the rock sample. These minerals are evidence of water.
3. The project is expected to last two years and cost $2.5 billion. Curiosity is not designed to look for microbes that may be alive on Mars today or inspect remains of life forms that no longer exist. Curiosity is the first Mars rover, but not the only one. The American space agency says it plans to send another rover, called Opportunity, to the red planet in 2020. Opportunity would be part of NASA’s plan to explore the Martian surface and atmosphere. The agency hopes to send humans to Mars in about 20 years.
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The American space agency announced …
one more project concerning exploring Mars by Curiosity rover
that there were some unknown chemical elements on the Martian surface
the existence of extremely small life forms on Mars
that in about two decades Mars can be visited by humans