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comment by NikolaiFyodorov
NikolaiFyodorov  ·  4328 days ago  ·  link  ·    ·  parent  ·  post: Astronomers discover remnants of 1,500 km long river on Mars.

How does that app measure elevation? After all, it can't be based on sea level.





user-inactivated  ·  4328 days ago  ·  link  ·  

Fascinating question that I can't answer. Some sort of normalized mean or mode?

NikolaiFyodorov  ·  4328 days ago  ·  link  ·  

I guess that's the only logical answer. I'd be curious to find out whether it takes into account massive elevation discrepancies like Olympus Mons.

NikolaiFyodorov  ·  3855 days ago  ·  link  ·    ·  

I realise it's 473 days since we had this conversation, but I've just finished reading this novel and I was overjoyed to discover an answer to the question. Elevation on Mars is based on atmospheric pressure. Zero altitude is defined as 610.5 Pascals.

So now we know.

user-inactivated  ·  3855 days ago  ·  link  ·  

Wow, that's so sensible. I love it.