As happens occasionally, a giant dust storm has arisen on Mars and the resulting cloudy sky has cut power to the Opportunity rover. Unlike the nuclear powered Curiosity, “Oppy” uses solar panels to supply its energy needs. The rover has been operating since landing on the Red Planet on Jan. 25, 2004 and survived a big storm in 2007 but this one appears much worse and may last longer.

This series of images shows simulated views of a darkening Martian sky blotting out the Sun from NASA’s Opportunity rover’s point of view, with the right side simulating Opportunity’s current view in the global dust storm (June 2018). The left starts with a blindingly bright mid-afternoon sky, with the sun appearing bigger because of brightness. The right shows the Sun so obscured by dust it looks like a pinprick. Each frame corresponds to a tau value, or measure of opacity: 1, 3, 5, 7, 9, 11.

NASA will hold a media teleconference today at 10:30 am PDT (1:30 p.m. EDT) to discuss the Martian dust storm and the status of Opportunity.

According to the latest update, Oppy has gone into a power saving state from which there is no guarantee it will recover: Opportunity Hunkers Down During Dust Storm

NASA engineers attempted to contact the Opportunity rover today but did not hear back from the nearly 15-year old rover. The team is now operating under the assumption that the charge in Opportunity’s batteries has dipped below 24 volts and the rover has entered low power fault mode, a condition where all subsystems, except a mission clock, are turned off. The rover’s mission clock is programmed to wake the computer so it can check power levels.

If the rover’s computer determines that its batteries don’t have enough charge, it will again put itself back to sleep. Due to an extreme amount of dust over Perseverance Valley, mission engineers believe it is unlikely the rover has enough sunlight to charge back up for at least the next several days.

The Martian dust storm that has blotted out the sun above Opportunity has continued to intensify. The storm, which was first detected on May 30, now blankets 14-million square miles (35-million square kilometers) of Martian surface — a quarter of the planet.

This global map of Mars shows a growing dust storm as of June 6, 2018. The map was produced by the Mars Color Imager (MARCI) camera on NASA’s Mars Reconnaissance Orbiter spacecraft.
The storm was first detected on June 1. The MARCI camera has been used to monitor the storm ever since.
The blue dot indicates the approximate location of Opportunity.

More at Opportunity hunkers down as dust storm descends over the intrepid little rover – NASASpaceFlight.com

June 12, 2018: This graphic compares atmospheric opacity in different Mars years from the point of view of NASA’s Opportunity rover. The green spike in 2018 (Mars Year 34) shows how quickly the global dust storm building at Mars blotted out the sky. A previous dust storm in 2007 (red, Mars Year 28) was slower to build.
The vertical axis shows atmospheric opacity and the horizontal access shows the Martian season, which is measured by where the Sun is in the Martian sky compared to its apparent position on Mars’ northern spring equinox

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