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Curiosity’s damaged wheels continue to appear stable despite the rough Martian terrain

A new look at Curiosity's worst wheel
To see the original images, go here and here.

The rover Curiosity on Mars has for more than two years been traveling across a very rocky and rough terrain as it climbs higher and higher on Mount Sharp inside Gale Crater. Since the rover’s wheels experienced far more damage than expected early in its mission, when it was on the floor of the crater where the terrain was not as severe, engineers have adopted a whole range of techniques to try to reduce any further damage.

First, they increased the safety margins on the software that guides Curiosity. It picks its way very carefully through the rocks, and stops immediately if it finds itself crossing terrain that is too rough.

Second, the science team does a photo survey of the wheels after every kilometer of travel. The two pictures to the right compare the damage on the rover’s most damaged wheel, with an image from the previous survey on top and the most recent image, taken yesterday, on the bottom. I have numbered the same treads, called grousers, in the two images to make it easier to compare them.

As you can see, it does not appear as if the damage has increased in the 210 sols or seven months of travel since the last survey. This wheel looks bad, but it is the worst wheel on the rover, and the strategies that the engineering team adopted years ago to reduce further damage continue to work, even as Curiosity traverses some very rough ground.

The software requires the rover to travel shorter distances in each drive when the ground is this rough, but the consequence is that it will last much longer, and thus have a better chance of reaching higher elevations on Mount Sharp.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

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