Critically, the dust raised the atmospheric opacity in Perseverance Valley, and Opportunity's power levels dropped significantly by Wednesday, 6 June, requiring the rover to shift to minimal operations. The courageous little rover is continuing to weather the storm; it sent a transmission back to Earth Sunday morning, which is a good sign.
The swirling dust is impacting Opportunity's solar panels, which it uses to recharge its batteries and power the heaters that allow the rover to function in the extreme cold conditions of Mars.
Indeed, as of June 8, the storm had swollen to more than 7 million square miles, enveloping Opportunity in the process: the rover's location is marked with a blue dot in the center of the image above.
Now, in a late-evening/night update yesterday at 16:30 PDT (2330 UTC) 10 June 2018, NASA announced that the current dust storm surrounding Opportunity at Perseverance Valley near the Endeavour Crater has grown to be worse than the 2007 dust storm, blocking even more sunlight than the global event did 11 years ago.
The Mars Reconnaissance Orbiter first spotted the beginnings of this super-storm on June 1st.
As of June 10, the storm had almost doubled the level of atmospheric opacity, or darkness, experienced by the rover in 2007, measured in tau.
"Full dust storms like this one are not surprising, but are infrequent", NASA officials said in the statement.
This is a problem for the rover because unlike its younger cousin Curiosity, Opportunity is solar-powered.
It's hard to complain about Earth weather once you realize just how insane it can get on Mars. It's unclear when the storm will eventually subside, but even if the storm ultimately doomed Opportunity it would have already vastly outlived its original mission. That storm, which covered the majority of the planet in 2007, also hampered its ability to gather vital sunlight and the rover was forced to remain in a low-power standby state around the clock.
For now, the engineers will just need to wait it out and see how the little robot comes through the storm.
'The rover has proved hardier than expected by lasting almost 15 years, despite being designed for a 90-day mission, ' the agency said.
"During southern summer, sunlight warms dust particles, lifting them higher into the atmosphere and creating more wind", the space agency says.
For the time being, NASA has temporarily shut down any scientific operations, which means turning off most instruments attached to the spacecraft. Without the heaters, the rover's batteries would likely fail and doom the mission.
"Engineers will monitor the rover's power levels closely in the week to come".
It will be balancing low levels of battery charge and sub-freezing temperatures.
The hope is that that won't be the case this time around, but storms are believed to have claimed Opportunity's twin rover, Spirit. Likewise, performing certain actions draws on battery power, but can actually expel energy and raise the rover's temperature.
The hardest working rover on Mars is fighting for its robotic life on the red planet.