Geologic Map of Mars
pubs.usgs.gov
pubs.usgs.gov
[1] http://pubs.usgs.gov/sim/3142/
[2] http://energy.usgs.gov/OilGas/AssessmentsData/WorldPetroleum...
Here's a file I found a while back. Not Mars related, but pretty amazing. The national file is a delimited txt file with just about every geographical point of interest in the U.S. I've imported it into a SQL database and now run queries against it when I'm looking for a weekend road trip.
Would there be a way to query wikipedia for the same type of information, or combine the two sources?
I can't think of a way to query wikipedia - not like this allows. Once this file has been imported into sql (I use SQL Server), I run queries like SELECT DISTINCT [feature_type] FROM dbo.nationalFile WHERE [state] = 'California'
This will give me a list of all types of features in California. From there, I'll see something that looks interesting (like "lava field" or "mine") and I'll run another query like SELECT [feature_name], [latitude], [longitude] FROM dbo.nationalFile WHERE [state] = 'California' AND feature_type='lava field'.
This will give me a very clear list list. I can't imagine there would be a way to do this with Wikipedia, or any other online source that doesn't offer an API.
https://www.wikidata.org/wiki/Wikidata:Main_Page
If you dig, I think you can find RDF dumps of the database.
The biggest problem is that they are choosing two represent two different dimensions of data(age/time period and terrain type), but are using seemingly random variations of hue to show these variations. Additionally, with so many distinct hues, it is nearly impossible to tell the difference between some areas on the map (for example, Hesperian basin unit and Hesperian polar look very similar).
A more effective way to visualize this data would be to apply a separate hue to the 8 categories of terrain unit, since these are categorical data points. Then, visualize the geological age on a brightness scale, since this is more of a quantitative measurement (obviously the current map also show the particular time period, we'll just ignore that for now). I think this would provide a much clearer view of the data, though you would lose a small bit of granularity.
http://pubs.usgs.gov/sim/3292/pdf/sim3292_pamphlet.pdf Page 10, search for the word color.
Edit: maybe this comment should have been a reply to https://news.ycombinator.com/item?id=8046656
I guess I spent too much of my childhood playing Role Master :-)