By Wednesday June 6th, Opportunity was in minimal operations mode because of sharply decreasing power levels.
NASA's Opportunity rover may not have to worry about running into traffic congestion on Mars, but vast dust storms are definitely an occupational hazard. To save power, the rover went days without phoning home to its controllers at NASA's Jet Propulsion Laboratory in Pasadena, California. It shows the growing dust storm and a blue dot indicating the rover's approximate location.
The main concern NASA has with this kind of tempest is that the rover's batteries will get too cold and it won't be able to function once the dust storm ends.
It was during that 2007 storm that Opportunity's handlers anxious about the rover's ability to power its vital survival heaters with the low power levels caused by that dust storm.
Despite this, Opportunity did call home yesterday through a communications relay with the Mars Reconnaissance Orbiter - a positive sign despite the worsening dust storm.
"There is a risk to the rover if the storm persists for too long and Opportunity gets too cold while waiting for the skies to clear", says NASA. It didn't take long for the dust storm to grow in size to cover more than 7 million square miles (11.2 million square kilometers), which is larger than North America. This suspension comes less than a week removed from the announcement that the Curiosity Rover had discovered "ancient organic matter" and "mysterious methane" on Mars.
Science operations for Opportunity are temporarily suspended while it waits out a Martian dust storm.
'The rover has proved hardier than expected by lasting almost 15 years, despite being designed for a 90-day mission, ' the agency said.
Back in 2007, at the height of that dust storm, Opportunity sustained two weeks of minimal operations and even ceased contact with Earth for several days in various attempts to conserve all the power possible aboard the rover. During summer in the south, the Sun warms dust particles, causing them to rise up higher into the sky. "That wind kicks up yet more dust, creating a feedback loop that NASA scientists still seek to understand".
Opportunity will work to recharge itself and achieve transmissions with engineers back on land communicating its state and showing the progress of the storm.
If that is not enough, and power levels drop to a specific, low level, Opportunity would trip what is known as a low-power fault program, disabling the rover's batteries and putting Opportunity into sleep mode until sufficient available energy returns to wake it up.
Scientists are anxious the rover won't survive this storm, but there's still hope.
Engineers will closely monitor the rover's power levels throughout the week, the agency says.
It will be balancing low levels of battery charge and sub-freezing temperatures. Likewise, performing certain actions draws on battery power, but can actually expel energy and raise the rover's temperature. It's lonely on Mars, but as this storm menaces Opportunity, the Red Planet suddenly seems even lonelier.
That's because Opportunity - like NASA's other Martian robots - relies on sunlight for power.