The Entirety of Mars is Now Covered By a Single Massive Dust Storm
Now, the dust storm has increased significantly in size and is officially considered a "global dust event" by NASA, encircling the entire circumference of Mars in thick clouds in dust. NASA's other active Mars rover, Curiosity, just began feeling the effects as visibility worsened around it, but the space agency is much more confident that the newer rover will successfully power through the storm as it waits in Gale Crater.
But while Gale Crater is experiencing a "tau" level - a measure of atmospheric opacity - of 8.0, which is the highest ever recorded in the region, the Opportunity rover's location is experiencing a higher tau of 11.0, which very little sunlight penetrating through the thick haze. Since Mars rovers run on solar power, this is a problem.
Mars Storm Watch: The dust storm now circles the planet. No signal yet from Opportunity, but no response is expected until skies begin to clear. We continue to listen daily. https://t.co/VwuuPwEpPA pic.twitter.com/8q7lDoezxs— Spirit and Oppy (@MarsRovers) June 20, 2018
When Opportunity was first hit by the storm, it recorded a little data before it was unable to continue powering itself and switched to an emergency standby mode. In this mode, it can't do much beyond periodically check to see if there's enough sunlight to charge itself up again, and there's a chance that Opportunity could break down permanently without its power-intensive heating system protecting its delicate electronics from the Martian cold.
With NASA unable to communicate with Opportunity, they're now relying on Curiosity to send back data and images of the global dust storm. It even sent back a photo of the "Duluth" hole it drilled with its recently-repaired arm (pictured above, right) to show how much darker the surface of Mars had become since the storm passed over.
Dust storms are common on Mars, although they're notoriously difficult to predict, and they don't typically grow as large as this current one. We don't know whether this will last days, weeks, or potentially months - to give some context, if this storm were on Earth, it has now grown large enough to cover all of North America and Russia too, for good measure.