http://www.newsweek.com/nasa-mars-dust-storm-opportunity-curiosity-990438

Earlier this month, NASA reported an enormous dust storm larger than North America had forced the agency to switch off most of its Opportunity rover's functions. Now, that storm has swelled, engulfing the entire planet in what the agency calls a "planet-encircling" dust event.

Attempts to make contact with Opportunity over the past few days have failed, and the future of the rover seems uncertain.