NASA Mars Exploration Rover Status Report, February 7, 2019: Mars atmospheric opacity (tau) over the rover site is estimated to be somewhere in the range of 0.9 to 1.3.
No signal from Opportunity has been heard since Sol 5111 (June 10, 2018) during the historic global dust storm. Opportunity likely experienced a low-power fault, a mission clock fault and an up-loss timer fault. The team is continuing to listen for the rover over a broad range of times, frequencies and polarizations using the Deep Space Network (DSN) Radio Science Receiver.
The team has begun mission clock fault recovery commanding “in the blind,” in the hopes of catching the rover during an awake period, as their strategy of last resort. Since loss of signal, over 835 recovery commands have been radiated to the rover. [More at link]