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What is the fastest rover currently moving on the surface of another celestial body? At what speed with our technology currently does physics restrict our speed limits on the surfaces of solar system bodies?

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    $\begingroup$ If you expect high speed rovers, you should provide high speed motor ways on other planets. $\endgroup$ – Uwe Jul 14 '18 at 18:26
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    $\begingroup$ @Uwe I do not possess the organizing talent to deliver such an infrastructure in time. $\endgroup$ – Conelisinspace Jul 14 '18 at 18:31
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    $\begingroup$ Does the Apollo Lunar Rover count? Because that was way faster than current robotic rovers. $\endgroup$ – Hobbes Jul 14 '18 at 18:53
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    $\begingroup$ The state today of the Lunar Rovers is discussed here: space.stackexchange.com/questions/2095/… $\endgroup$ – Hobbes Jul 14 '18 at 19:44
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    $\begingroup$ You surely do not mean in space, but on the surface of other celestial bodies? $\endgroup$ – Polygnome Jul 15 '18 at 7:55
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The manned Apollo Lunar Roving Vehicle from Apollo 17 holds the record of 17km/h achieved by Eugene Cernan. Apollo Lunar Roving Vehicle was also present on Apollo 15 and 16.

For traditionally understood rovers - unmanned mobile landers, the fastest historically would be Lunokhod 1 and 2, capable of 2km/h.

At current time only two rovers are still active and operational: Curiosity: 0.14 km/h and Opportunity: 0.18 km/h.

Let's add for the record: Yutu: 0.2 km/h, Spirit, same as Opportunity: 0.18 km/h, Sojourner: 0.024 km/h. I believe this is the complete list of rovers that actually drove over the surface of remote celestial bodies to date.

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    $\begingroup$ Hundred and forty meters per hour!? That is unbelievably slow. Wow! $\endgroup$ – sampathsris Jul 15 '18 at 5:06
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    $\begingroup$ Still faster than Southern Rail $\endgroup$ – James K Jul 15 '18 at 13:39
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    $\begingroup$ @Krumia: Note how every couple meters there's an interesting rock formation that is worth analyzing. Therefore it's practically unheard of for it to drive continuously for more than a couple minutes. (and how do you like Sojourner's 24 meters per hour?) $\endgroup$ – SF. Jul 15 '18 at 14:18
  • $\begingroup$ Did Yutu actually drive at 0.2 km/h ? Do you have a link ? $\endgroup$ – Conelisinspace Jul 15 '18 at 16:19
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    $\begingroup$ The rovers could drive much faster if they had a flat, hard, level surface without obstacles. They could be as fast as autonomous cars on Earth if there is the necessary power and a surface comparable to a road. $\endgroup$ – Uwe Jul 15 '18 at 20:21
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The highest speed was recorded by an Apollo Lunar Roving Vehicle:

The rovers were designed with a top speed of about 8 mph (13 km/h), although Eugene Cernan recorded a maximum speed of 11.2 mph (18.0 km/h), giving him the (unofficial) lunar land-speed record.

Unmanned rovers have much lower top speeds. Their speed is limited by the amount of terrain they can see and by the amount of autonomy they have. Curiosity has 3 driving modes:

  • fully programmed (using one sol's images to plan driving for the next sol in detail). This is the fastest mode.
  • partly programmed
  • autonomous, with image analysis (finding the safest route, checking for slope angles and obstacles) happening onboard. This is limited by onboard computer power, and is the slowest driving mode.

"Curiosity takes several sets of stereo pairs of images, and the rover's computer processes that information to map any geometric hazard or rough terrain," said Mark Maimone, rover mobility engineer and rover driver at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The rover considers all the paths it could take to get to the designated endpoint for the drive and chooses the best one."

Curiosity's top speed is 137 meters/h (0.085 mph).

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    $\begingroup$ More about autonomous operation of the Curiosity rover in the informative answers to How much can the Mars rover Curiosity do autonomously, after four years of operation? $\endgroup$ – uhoh Jul 15 '18 at 0:20
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    $\begingroup$ I'd think that practicality is also important. The lunar rovers wouldn't be useful if they didn't travel faster than an astronaut could walk, whereas nobody cares much about how fast an unmanned rover goes. $\endgroup$ – David Thornley Jul 16 '18 at 18:05
  • $\begingroup$ @DavidThornley A fast unmanned rover maybe could explore two proposed landing sites, like NE Syrtis major and Jezero crater $\endgroup$ – Conelisinspace Jul 17 '18 at 8:19
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To answer the second half of the question: rover speeds are primarily limited by practicality, rather than the physics or technology needed to drive on an extraterrestrial surface. As Elon Musk demonstrated, it's physically possible to send a very fast land vehicle out of Earth's gravity well. If you wanted to waste a lot of money, you could put a 200 kmh rover on another world. However, no scientific agency does this, because space launches are expensive and mass-limited. Every gram you use for motors, wheels, or suspension is a gram that you can't use for experiments or communications. No luxury seats with Corinthian leather either.

The Mars rovers have extraordinarily light weight wheels, and just enough motor to traverse the difficult terrain (with appropriate safety margins). High speed is neither necessary nor particularly desirable.

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    $\begingroup$ That very fast land vehicle of Elon Musk will be totally useless when placed on Mars or Moon. $\endgroup$ – Uwe Jul 16 '18 at 16:12
  • $\begingroup$ Good link to the wheels though ! $\endgroup$ – Conelisinspace Jul 17 '18 at 8:12
  • $\begingroup$ @Uwe, I'd bet there are a few flat spots on Mars where a consumer electric car could drive, but even if not, existing rover speeds are orders of magnitude below what's possible. $\endgroup$ – Foo Bar Jul 18 '18 at 16:58

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