As reported by NASA, the dust tempest did cover more than 18 million square kilometers (7 million square miles) of the Red Planet, which stretches bigger than the entire possession on the Earth by North America. If the sunlight is blocked for an extended period, the rovers will not generate enough power to operate.
On June 6th, 2018, NASA has released a global map of Mars which was captured by Mars Reconnaissance Orbiter, and in the map, it shows that the growing dust storm and in the middle a tiny blue dot which resembles the position of the rover. On Mars, dust storms can crop up suddenly, NASA said in a statement, but it could take weeks or even months for them to subside. The same could not be said for Opportunity's companion probe, Mars Spirit, which failed completely after a dust storm in 2008.
NASA's Opportunity rover has survived on Mars much longer than originally intended, but the planet is testing the little robot right now. This produces more wind, which kicks up even more dust, creating a feedback loop. Nighttime on Mars is extremely cold, but using Opportunity's heaters can drain the batteries.
NASA's MER-B is threatened by vast dust storm that may put the Opportunity rover into vocational hazard. The storm lasted several days and blocked 99 percent of direct sunlight to the rover.
The dust has blotted out the Sun in many regions, including Opportunity's current location at Perseverance Valley.
Dust storms on Mars are a well known phenomenon but are infrequent.
"The previous storm had an opacity level, or tau, somewhere above 5.5; this new storm had an estimated tau of 10.8 as of Sunday morning". Ultimately, the storm ended and Opportunity got back to work.
Presently, engineers will monitor Opportunity's power levels closely in the week to come. The agency had to switch to two weeks of minimal operations and cut off contact with rover for days in order to save power. "The rover needs to balance low levels of charge in its battery with sub-freezing temperatures".
Despite this, Opportunity did call home yesterday through a communications relay with the Mars Reconnaissance Orbiter - a positive sign despite the worsening dust storm.
"Its heaters are vitally important to keeping it alive, but also draw more power from the battery", NASA wrote in a recent update. "Now that could be very deep inside Mars, but to be able to see that at the Martian surface today when we think that Mars has been mostly dead for about 3 billion years, it kind of contradicts that story, it tells us maybe Mars isn't quite as dead as we've been thinking it is".