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How the Heck Does GPS Work?

by alfanick on 4/22/2026, 9:22:05 AM

https://perthirtysix.com/how-the-heck-does-gps-work

Comments

by: NooneAtAll3

Page tries to load, then goes:<p>404 Page not found<p>Sorry, we couldn’t find the page you’re looking for

4/22/2026, 11:59:02 AM


by: delamon

This blog post is also worth noting: <a href="https:&#x2F;&#x2F;ciechanow.ski&#x2F;gps&#x2F;" rel="nofollow">https:&#x2F;&#x2F;ciechanow.ski&#x2F;gps&#x2F;</a>

4/22/2026, 10:31:14 AM


by: openclawclub

Great explainer. The part about atomic clock synchronization always gets me — the satellites carry atomic clocks accurate to 1 nanosecond, and the system has to account for both special AND general relativistic effects (the satellites experience different gravity AND they&#x27;re moving fast enough that time dilation matters).<p>The correction factor is about 38 microseconds per day — small enough to ignore in everyday life but catastrophic for GPS accuracy if unaccounted for. No other engineering system relies on relativistic corrections in its day-to-day operation quite like this.

4/22/2026, 11:08:58 AM


by: keyle

Always makes me laugh when you get some dimwit that claims the Earth is flat, but then uses Google maps in his car. Magic!<p>GPS are amazing. If you understand how they work, and how they reliably know the time etc. you&#x27;d think you live in the future; and yet it&#x27;s everywhere, in our pockets.

4/22/2026, 11:07:27 AM


by: codethief

For anyone interested in a more detailed account of (general-)relativistic effects in GPS and other positioning systems, I really liked this article: <a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC5253894&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC5253894&#x2F;</a>

4/22/2026, 11:00:19 AM


by: sinaatalay

Very cool to see these browser-native interactive 3D visualizations! Gives this such a different energy than a regular blog post would have had.<p>I&#x27;m guessing those visualizations wouldn&#x27;t be in this post if it weren&#x27;t for AI. The interesting question is what happens when ed-tech ships this pattern at scale. Exciting future.

4/22/2026, 10:38:02 AM


by: gobdovan

Pretty cool. Would be nice to have the equation system as well in a recap, and the math not collapsed by default. Also had to look up other resources to understad that time correction refers to correcting a relatively short window of time, as it was not clear that receiver clock is actually accurate enough for short periods (milliseconds) to treat as affine.<p>So the trick, as always, boils down to engineering approximations, haha.

4/22/2026, 10:00:50 AM