There's reason to be optimistic about Mars Opportunity rover that has been silent since June 10, after getting caught in a massive dust storm on the Red Planet that cut off solar power for the nearly 15-year-old rover, NASA said in a statement.

According to the scientists, the global dust storm is "decaying" -- meaning more dust is falling out of the atmosphere than is being raised back into it. As a result, skies might soon clear enough for the solar-powered rover to recharge and attempt to "phone home." Studies on the state of batteries and temperatures at the location showed that they were relatively in good health before the storm, and there is not likely to be too much degradation.