The Mars rover Opportunity confirmed the discovery made before Curiosity. It found proofs that in the ancient time there was water on Mars, which is suitable for live organisms. Earlier data from automatic probes testified that Martian water differed extreme high salinity and acidity. In March Curiosity mars rover obtained the evidence that Martian environment in the ancient time was suitable for life. In particular, that water on Mars was almost fresh and neutral. Now results of work of the Curiosity rover confirmed this find. Mars rover Opportunity studied a chemical composition of a stone to which the scientists appropriated Esperance 6 designation. They fix a ratio of aluminum, potassium, calcium and sodium, and also iron in clay breed in cracks of the stone. This clay could be formed only in the presence of a large amount of water. It became clear that this water on Mars was fresh. By the words of scientists it was water which you could drink. Still on Mars found traces of water, which was more similar to sulfuric acid. This result is one of the most important finds for all missions. Now the Mars rover Opportunity goes to the new area for continuation of research work. In particular to Solander Point, where there is an exposure of breeds with a large number of the layers interesting from the geological point of view.