Great-circle distance

"Great circle distance" is the distance between any two points on a sphere.

It is commonly used to find the distance (e.g. in miles) between two coordinates (latitude/longitude pairs) on a map.

latitude is $\delta$ longitude is $\lambda$

The formula is:

Failed to parse (unknown function "\DELTA"): {\displaystyle \DELTA = \lambda' - \lambda}

$dlat=\delta '-\delta$

$a=(\sin {({\frac {dlat}{2}})})^{2}+\cos {\delta }*\cos {\delta '}*(\sin {({\frac {dlon}{2}})})^{2}$

$c=2*\arcsin {(\min {(1,{\sqrt {a}})})}$

$d=R*c$