Mystery Rock ‘materializes’ In Front Of Opportunity Rover, Scientists Scratch Heads

A comparison of two raw Pancam photographs from Sols 3528 and 3540 shows a new rock about 3-inches across suddenly appearing out of nowhere a few feet in front of the rover. A Sol is a Martian day which is equal to 24 hours 37 minutes.  Credit: NASA/JPL-Caltech

Whoa – wait a minute. The first picture taken by the Opportunity Rover shows no rock. The second, taken of the exact same spot 12 Mars days later, shows a very real rock. How’d that get there?

The shadow of the Opportunity Rover stretches across the barren Martian landscape. Credit: NASA/ JPL-Caltech

The discovery was revealed by Mars Exploration Rover (MER) lead scientist Steve Squyres in a 10 years of Roving Mars keynote address at NASA’s Jet Propulsion Laboratory last night. MER scientists immediately named the new rock “Pinnacle Island”.

Scientists are still scratching their heads as to how that rock could move, but there are two intriguing possibilities, one of them unlikely and another so ordinary, it almost has to be true.

Squyres thinks it’s either a stone blown out from a meteorite impact that happened to land in front of the rover or, more likely, a rock flicked like a tiddlywink when the rover performed a turn in place not far from where the rock now lies. Or the rock got stuck earlier in a rover wheel and dropped out during the maneuver.

A higher resolution view of the mystery rock photographed by the Opportunity Rover. Credit: NASA/JPL-Caltech

Not ones to miss a scientific opportunity, Opportunity scientists hope to study the bright rock. “It obligingly turned upside down, so we’re seeing a side that hasn’t seen the Martian atmosphere in billions of years, and there it is for us to investigate. It’s just a stroke of luck,” Squyres said.

Opportunity’s front right steering actuator or motor has stopped working, so Squyres identified that as the possible culprit behind the whole mystery. Each wheel has its own actuator; the jam in the one wheel prevents it from turning left or right.

As the rover did a turn in place on the bedrock, the faulty wheel may have shot out the rock something like your car’s wheels blasting ice chunks out when you gun the engine to get out of a snow drift.

View of “Greeley Haven” on the rim of Endeavour Crater taken by Opportunity. It was assembled from 817 component images taken between Dec. 21, 2011, and May 8, 2012. Click to enlarge. Credit: NASA/ JPL-Caltech

Still, no one knows for sure how it got there. A pal of mine suggested a blast of Martian wind. We’re lucky Opportunity found the intruder. The rover’s been parked at the same spot for weeks as it waits for better weather and a higher sun to help power it along its way. Sticking around the same spot allowed for nearly identical images to be taken on widely-separated Sols. Maybe a closer study of the rock in the coming days will tell us more about how it got there.

Despite being designed for a 90-day mission, the robot-that-could is still kicking 10 years later with more than 23 miles on its odometer. To check out the high resolution, raw images yourself, here are the links: Sol 3528 and Sol 3540.

12 Responses

  1. Jim Schaff

    Hi Bob,

    Maybe it is a Martian playing games with us earthlings. In all seriousness, what a cool event to happen. I hope it is a meteorite or tektite.

    On a different note, I saw Venus yesterday morning very low, my first sighting since inferior conjunction.


    1. Sean

      nice job with Venus Jim. i hope to spot it soon! a lot of clouds and fog these days tho, and i’ve slept thru other opportunities – out of curiosity, any optical aid to make the initial sighting?

        1. Giorgio Rizzarelli

          Rocks appearing suddenly, shiny metal objects, shrimp-like plastic envelopes… these martians are kidding us

    1. astrobob

      Oh ye of little faith. Yes, it’s on Mars otherwise Steve Squyres, head scientist for the Opportunity Mission, wouldn’t have shared it with the public in the first place. Do you really believe he’d concoct such a thing? What possible motive would he have? Go to the Opportunity site and you can explore thousands of images taken over the probe’s 10 years of exploration. These are just two of many from Mars.

Comments are closed.