The Earth is not a sphere
Vincenty
Implemented in the geospatial extension:
Jeb lives at 45.74, -47.11
KSP is at -74.575277777778, -0.1025
'Point', 'coordinates' => [ 45.74, -47.11 ] ];
$ksp = [ 'type' => 'Point', 'coordinates' => [ -74.57527, -0.1025 ] ];
var_dump(vincenty($jeb, $ksp));
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