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0 pointsbobthepanda2y ago0 comments

GPS is only accurate up to 16 feet, and unless you are very close to an earthquake or other deformation source probably everything around you has moved by the same amount.

Most people only use GPS for local navigation.

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KeplerBoy2y ago

GPS is much better than 16 feet these days.

Nobody asks google maps for instructions how to move 10 miles southwest. We ask it to provide a route to a specific latitude and longitude, that's global navigation and that, of course, doesn't work if the place you want to get to has gotten new coordinates overnight.

bobthepandaOP2y ago

That 16 ft figure is provided by the government. https://www.gps.gov/systems/gps/performance/accuracy/

And of course, satellite navigation is worsened by the urban canyon of buildings, terrain, trees etc so super accurate navigation also uses local cell towers, which are also shifting by the same magnitude and direction as you and your local destination.

Ultimately people only really need to get to the rough city block of where they need to be, and so as long as buildings are not shifting hundreds of feet a year it is mostly not noticeable.

pxeboot2y ago

From that source:

> GPS-enabled smartphones are typically accurate to within a 4.9 m (16 ft.) radius

Smartphones were typically optimized for speed and battery life, not accuracy. Now that Multi-Band GPS is available on high end smartphones, they tend to be more accurate.

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