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Rover update: Curiosity pauses to drill

Curiosity's entire journey so far in Gale Crater

Overview map of Curiosity's recent travels

The artist’s oblique drawing above, as well as the map to the right, provide some context as to Curiosity’s present location and its entire journey in Gale Crater. For the overall context of Curiosity’s travels, see my March 2016 post, Pinpointing Curiosity’s location in Gale Crater. For all rover updates since then through May 2020, go here.

Since my last update on July 7, 2020, Curiosity has quickly moved a considerable distance to the east, as planned, skirting the large sand field to the south in its journey to the best path upward onto Mt. Sharp. The science team however has detoured away from their planned route, shown in red on the map, heading downhill a bit in order to find one last good location in the clay unit to drill. They are at that location now and are presently scouting for the best drilling spot.

About a week ago, before heading downhill, they had stopped to take a set of new images of Curiosity’s wheels.

Damage on one of Curiosity's wheels over the past year
For the full resolution images, go here for
the top image and here and here for the
bottom image.

The engineers wished to gauge how the rover was doing in the first six weeks of its fast-paced journey east. They had surveyed the wheels in May, and thought it wise to look at them again to see if any significant changes had occurred.

The two images to the right provide some encouragement. The top image of this wheel was taken more than a year ago. The bottom mosaic, compiled from two images, was taken last week. In comparing the same tread sections, as indicated by the numbers, it appears there has been little or no new damage in that year, and in fact, because of the lighting, it almost appears as if some the broken openings have actually gotten smaller.

From this one comparison it appears that the care the engineers have been taking over the past three years to protect the wheels from damage continues to work. Of course, this is only one section of one wheel, and Curiosity has six total. I have not done a survey of them all, so it could be that other wheels have deteriorated more.

Regardless, this one comparison suggests that the wheels are holding up, and that Curiosity’s journey will continue unhampered.

Once they complete this week’s drilling effort, expect the rover to quickly head east again, aiming for the gap between the very rough Greenheugh Piedmont and the first steep cliffs of Mt. Sharp. They hope to reach this point in the fall, when the rover will finally leave the foothills of Mt Sharp and begin climbing the mountain. Their goal is the dark canyon in the first image above, uphill from where Curiosity sits now.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


  • Star Bird

    The idea of Canals on Mrs is probibly one reson H.S. Wells wrote WAR OF THE WORLDS

  • space follower

    Ar the wheels made of some plastic that the heat/cold cycle caused to crack? Or was it sharp rocks? They look paper thin and fragile and the temp fluctuations were known so I’m annoyed they have such damage.

  • space follower: In order to save precious weight, everything on this kind of rover is designed to minimize its mass and weight. Thus, when they designed the wheels they did so based on the minimum strength they needed to withstand travel on the rough Martian surface. They based this design partly on what was learned with Spirit and Opportunity.

    However, Curiosity is a lot heavier and bigger, and they learned in the first two years of travel that when they did not take great care about the routes they chose the wheels as designed would get damaged. Since then they have done a lot to pick more gentle paths, and the result has been that new damage has been greatly reduced.

    The wheels of Perseverance were designed with this knowledge in mind, and should hold up much better.

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