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Rover missions are hard - you need to put them down somewhere where they can safely drive around and measure (hopefully a variety of) interesting things.

Future rovers may have legs as discussed in this answer and the ability of various legged motilities may open access to much more territory. I'm curious roughly how much.

For the various Mars rover missions, I am guessing that maps were made of "interesting" areas and "drivable" areas, and then they were overlaid for simultaneous compatibility, though I am sure it was a far more complex process.

Are there any kind of rough estimates of what areas of Mars would be relatively safe to land a rover so that it could do a substantial amount of driving, and which of those areas, either due to boulders or sand or inclines or other reasons not so safe? Is there anything like a "rover-friendly region map" estimated for Mars available somewhere?

Another similar question has been posed for the moon: Are there "rover-friendly region maps" for the Moon?

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Mars is mapped to a degree, you can explore Mars on "Mars Trek".

MRO (Mars Reconnaissance Orbiter) is used to look for potential obstacles for the various rovers.

Mars Reconnaissance Orbiter is looking at small-scale features In its survey of the red planet, the Mars Reconnaissance Orbiter is increasing tenfold the number of spots surveyed close-up. One of the orbiter's cameras is the largest ever flown on a planetary mission. Though previous cameras on other Mars orbiters could identify objects no smaller than a school bus, this camera can spot something as small as a dinner table. That capability has allowed the orbiter to identify obstacles such as large rocks that could jeopardize the safety of landers and rovers, including the Phoenix mission and Mars Science Laboratory mission. Its imaging spectrometer looks at small-scale areas about five times smaller than a football field, a scale perfect for identifying any hot springs or other small water features.

Still, the MRO's resolution is limited so the rovers take images and send them back to the planners for analysis.

The Lunar equivalent of the MRO is unimaginatively called the LRO. Its mission is to map the lunar surface and identify potential landing sites, find resources that could be used in a future, etc.

I think there are other spacecraft dedicated to mapping the Moon, the Indian Chandrayaan-1 comes to mind, but I don't know what else is currently there.

Here is a good article that describes what sites NASA is considering for the Mars 2020 rover.

Basically, the two main considerations are what's the scientific value of the site and given the engineering constraints, how much of the objectives can be achieved.

You probably want to consider elevation data - it seems the rovers we do send to Mars are meant to work on fairly flat surfaces. You can kind of see flatness on "Mars Trek" but there are also elevation maps. Dust cover, verticle roughness and other datasets can be found here. If the rover has solar panels you probably care about illumination data as well as some of the craters might be in permanent darkness.

The rover-friendliness of the potential landing site is just one factor, the scientific value of the site is usually given higher importance and the design of the rover is a compromise between science value and development cost.

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  • $\begingroup$ OK for an answer I need some more information. I see a picture there, but is there terrain? Surface roughness? Sand vs rock? Would radar be better? How can I use that web site to address the question about which regions might be rover-friendly? Thanks! $\endgroup$ – uhoh Oct 24 '16 at 1:57
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    $\begingroup$ That depends on the capabilities of your rover. You can start by looking at elevation data - it seems the rovers we do send to Mars are meant to work on fairly flat surfaces. You can kind of see flatness on "Mars Trek" but there are also elevation maps: jmars.mars.asu.edu/maps/?layer=MOLA_Color $\endgroup$ – ventsyv Oct 24 '16 at 19:49
  • $\begingroup$ Dust cover, verticle roughness and other datasets can be found here: mars.asu.edu/data. I'll look for similar datasets for the Moon. $\endgroup$ – ventsyv Oct 24 '16 at 19:52
  • $\begingroup$ If the rover has solar panels you probably care about illumination data as well as some of the craters might be in permanent darkness. $\endgroup$ – ventsyv Oct 24 '16 at 19:57
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    $\begingroup$ @uhoh Good point. I'll add them to the answer. $\endgroup$ – ventsyv Oct 25 '16 at 16:31
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A rover-friendly map needs more than altitude/slope data. It also needs information on the geology of the terrain: composition, grain size, etc. It needs to show features like a hard crust with soft sand underneath (which tripped up Spirit and Opportunity), and things like sharp rocks (which have damaged Curiosity's wheels).

Some of this can be derived from photos, but you may also need spectroscopic data and/or imaging in other wavelengths.

The experience of Spirit, Opportunity and Curiosity suggests we're not quite yet at the point where imaging from orbit provides enough data to be able to plot a route that doesn't contain surprises.

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  • $\begingroup$ You are right - I suppose I could change the question to "map of potentially rover friendly" or "potentially rovable topography", since without extremely thorough mapping there really can't be any guarantees. I was actually interested to ind out if there were any existing hybrid maps that have been made generally public that might show some kind of "rovability merit function". $\endgroup$ – uhoh Jan 30 '17 at 1:30
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From the Lunar Reconnaissance Orbiter (LRO), there is laser altimeter, temperature and imaging data available: https://lunar.gsfc.nasa.gov/resources.html

The altimeter data is pretty sparse, so it is good to get information about craters, large obstacles and overall slope, but not good for finding rover-sized rocks. However, the temperature data is related to the frequency of rocks so it can be used to help estimate how many smaller rocks there are in a region.

Usually discussion of the LRO data (for example in a scientific paper) references Apollo data and images to make some assumptions about surface conditions.

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  • $\begingroup$ Wow, there is quite a lot of information there! You could consider adding those two nice color figures (time plot and GIF) found on this page in your answer and explaining them a little bit - why time is important. Actually, why don't I split the Moon off from this question and ask separately. Just a sec... $\endgroup$ – uhoh Jan 27 '17 at 16:40
  • $\begingroup$ Would you consider adding this answer to this new question? You don't need to remove it here necessarily, but it will be easier for people to find your answer with the new question specifically about the Moon. $\endgroup$ – uhoh Jan 27 '17 at 16:50

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