Lat/Lng coordinates don't necessarily mean anything without knowing if it's WGS84 vs. something else. If a ship/crew/captain were to send an SOS call out with just coordinates, do they have to say WGS84?

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    Most possible ways for the captain to know where they are would be based on WGS84 (not that would matter if the ship were on fire or such), though this isn't really a GIS-centric question (and might be better suited to The Great Outdoors).
    – Vince
    Commented Mar 31, 2020 at 20:15

1 Answer 1


It is implied and assumed, partly because WGS84 is the standard for GPS. It also doesn't matter, because the if the datum were confused (eg to NAD83), the deviation is small compared to the accuracy of the GPSes.

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