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"Canyon? But I was just following the satnav..."
NASA's famous nuclear-powered, raygun-armed Mars rover Curiosity has broken free of human control and made up its own mind where to drive across the rusty plains of our neighbour world, according to boffins at the space agency who were formerly in charge of it. Mars rover Curiosity route. Credit: NASA/JPL-Caltech No, I WILL …
Actually that does raise a question...
We're all very familiar with track maps like that here on earth, but that's because we can always tell where we are thanks to the orbiting satellites... But they're orbiting Earth, not Mars, so not much use there.
So how do they track the location of the Rover? I can only assume by dead reckoning, not exactly a million miles from a Logo turtle with left 45 forward 100... And we all know how quickly that become inaccurate!
...I haven't updated the maps and on my 3-billion year out-of-date set it shows a river crossing by ferry right at that point..."
Email from Garmin:
"Dear M. Rover, Thank you for your enquiry regarding updating the maps for region: MARS ALL REGIONS. The price for the one-off set is US$154million, this being the total for the Mars Global Surveyor mission divided by the number of active users in your area. I am sure you will agree that this is a fair way of pricing this update and I look forward to receiving your order soon. We recommend using fibre broadband for the download as it is a large map set and at your current connection speed it would take approximately 365sols to complete..."
There's probably some spotty kid, sat in his bedroom in Shanghai or Pasadene, buzzing on cola and Chitos that's found this really interesting remote controlled device that he's hacked into...
Either that or it's being towed by the Martian equivalent of a clamping firm. Going to cost NASA 3 million quatloos to get it out of their vehicle pound.
I still want to see a speedy autonomous lunar rover. It will be solar powered, and will drive itself around and around the moon, staying on the sunlit side all the time so it can keep going forever (or at least until some essential moving part wears out).
How fast does it need to be? The moon's circumference is 10,921 km at the equator, and the moon's day is 27.321582 of our Earth days, so that gives a straight-line speed of 16.655 km/h. Let's give it a nice round number and say a steady speed of 20 km/h to allow for course deviations to avoid big craters and mountains. That's not very fast. Way back in 2005 the winner of the DARPA Grand Challenge averaged 30.7 km/h.
The rover can be provided in advance with fairly detailed maps of a preferred route around the moon which avoids all the larger obstacles, so all it needs to do itself is keep an eye out for boulders ahead. It can remember where those boulders are for next time around, and optimise the route. It can then start trying alternate routes. In the event that it gets stuck in a dead end and dusk catches up, it can go into sleep mode and then backtrack the next morning.