For weeks, Mars has been besieged by a large dust storm. A thick haze fills the environment and blots out the solar, immersing a lot of the Red Planet in an impenetrable, perpetual night time.
Caught in the center of all of it is NASA’s Opportunity rover, a five-foot-tall, bear-sized spacecraft that has already defied the percentages by surviving on Mars greater than 55 instances longer than initially deliberate.
For the solar-powered robotic, the dust is not as harmful because the darkness. Since the storm started two weeks in the past, the quantity of sunshine the spacecraft receives has dropped to lower than 1 p.c of regular ranges. Energy manufacturing has fallen from tons of of watt-hours a day to nearly nothing. NASA has not heard from the rover since Tuesday.
This is a “spacecraft emergency,” Mars Exploration Rover challenge supervisor John Callas mentioned Wednesday. His group is working below the belief that the cost in Opportunity’s batteries has dipped beneath 24 volts and that the rover has entered a low-power fault mode, when all subsystems besides the mission clock are turned off.
The clock is programmed to awaken the rover at periodic intervals to verify whether or not gentle ranges are ample to get up — a state referred to as “solar groovy.” But the storm is nonetheless rising and may encircle the planet in a matter of days. NASA expects that it is going to be weeks, if not months, earlier than the dust clears sufficient to permit the spacecraft to show again on.
Though the rover is anticipated to outlive the storm, “It’s like you have got a liked one in a coma in the hospital,” Callas mentioned. “The docs are telling you, ‘You simply gotta give it time and she or he’ll get up.’ But if it is your 97-year-old grandmother, you’re going to be very involved, and by all means we’re.”
Opportunity, together with Spirit, its twin, landed on the planet in 2004. Though the mission was solely speculated to final 90 days, Opportunity is approaching its 15th 12 months there. Before the storm started, it had been rolling down a channel referred to as Perseverance Valley, which scientists assume could have been carved by water billions of years in the past.
NASA’s important fear now is that the rover’s batteries could freeze with out the warmth generated by its regular operations. (Opportunity is designed to face up to temperatures as little as minus 55 levels Celsius.) Other issues could come up if the rover’s vitality ranges drop even additional. That would set off a “clock fault,” when the rover loses monitor of time completely.
Fortunately for NASA, dust storms are likely to entice radiation, stopping the form of wild temperature swings that always happen on Mars. Callas additionally expressed religion in Opportunity’s batteries — despite the fact that they’re 15 years outdated, they’re nonetheless working at 85 p.c of their capability.
“They’re the finest batteries in the photo voltaic system. I want my cellphone battery had half of that,” he mentioned.
Local dust storms are a widespread incidence on Mars — sturdy winds carry particles the dimensions of talcum powder and carry them into the sky. The skinny environment makes these occasions totally different from storms on Earth; even probably the most highly effective Martian winds could not topple a rover. But that environment additionally makes it simpler for daylight to warmth the dust and loft it increased and better. It could take weeks for the clouds to clear.
Scientists aren’t positive what causes big, planet-scale dust storms just like the one now raging. They appear to happen each three to 4 Mars years (six to eight Earth years), and so they normally occur when the planet is at its closest to the solar.
An analogous storm in 2007 severely broken Spirit, blanketing the little robotic’s photo voltaic panels and reducing its vitality manufacturing to lower than half of regular capability. Spirit later acquired caught in a sand entice, the place it couldn’t angle towards the solar in the winter, and has been silent since 2010.
This present storm is “unprecedented in the pace at which it has grown and spread across the globe,” mentioned Rich Zurek, chief scientist for the Mars Program Office at NASA’s Jet Propulsion Laboratory. It covers nearly a quarter of the floor of Mars, an space the dimensions of North America and Russia mixed. Its tau — a measure of how a lot gentle is being absorbed — is 10.eight, the very best ever recorded.
Even on the alternative facet of the planet, the place the Curiosity rover is parked at Gale Crater, the thick crimson haze nearly fully obscures the horizon. (Curiosity, which landed in 2012, is nuclear-powered and largely unaffected by the dust.) The storm is being monitored by a fleet of orbiting spacecraft, significantly the Mars Reconnaissance Orbiter. Its wide-angle digicam first detected the occasion.
NASA is deeply in understanding the triggers of those main storms, Zurek mentioned. The company’s subsequent rover mission — Mars 2020 — is additionally photo voltaic powered. And if the area company goals to someday ship astronauts to the Martian floor, it would most likely like to guard them from dust clouds, too.
Meanwhile, “we’re all pulling for Opportunity,” Mars Exploration Program director Jim Watzin mentioned. “It’s a remarkably resilient little rover.”