After nearly 15 years of lonely wheeling about on the surface of Mars, NASA’s Opportunity rover has gone quiet.
The problem, NASA says, is this – the Martian sun now, far right, compared to how it should look to Opportunity:
That dust storm, which was first detected on May 30, now blankets 41 million square kilometres of Mars. That’s nearly a quarter of the planet, or the area of North America and Russia combined.
Alone, it’s food for thought for any humans feeling some high adventure awaits when they try to live there in the next decade or so.
But right now, NASA’s main concern is whether Opportunity has died, or if it has simply shut down because the charge in its batteries has fallen below 24 volts.
They’re hoping it’s the latter, because that’s supposed to happen. Low power fault mode is the condition where all subsystems, except a mission clock, are turned off.
As it stands, they’re calling it a “spacecraft emergency”.
NASA says Opportunity’s mission clock is programmed to wake the computer so it can check power levels and decide whether it can wake up again, or go back to sleep.
That’s critical because if its timing gets somehow thrown out, it might wake up when the sun isn’t out, and go back to sleep before NASA can contact it to tell it not to.
If that cycle continues, the rover may eventually get too cold to operate, and things could get broken. In 2010, Opportunity’s twin Spirit suffered that exact fate, freezing to death after getting stuck in thick sand.
Opportunity has eight heating units to draw upon for some time yet, and can handle drops to -55C.
Opportunity project manager John Callas told a press conference that NASA believes Opportunity will only drop to -36C and as such, “we think we can ride this out for a while”.
If you’re into symbolism, it’s stuck under the dust cloud in Perseverance Valley, so maybe there’s some strength to be drawn from that. But on the scientific side of things, NASA’s team reckons it will be at least several days before they know if the rover will be able to power itself back up again.
Also, in 2007, Opportunity survived a dust storm that saw it shut down for two weeks, but the dust wasn’t as thick as it is right now.
And even if it doesn’t, the team says there’s still plenty to learn from the experience.
Over on Curiosity’s side of the planet, it’s taken a photo that shows the dust storm moving in on its locale at the Gale Crater:
There’s not nearly as much concern for Curiosity though, as it’s nuclear-powered.