If you're tracking your iPad via Apple's order status page, you may be wondering why it travels from Shenzhen, China to Anchorage, Alaska instead of UPS' WorldPort shipping hub located in Louisville, Kentucky.

UPS and FedEx built multi-million dollar logistics centers in Anchorage, Alaska because of its advantages in range vs. payload and spherical coordinates, the shortest path between two points on a surface.

ZDNet's own Christopher Dawson researched it as part of a grad school project inspired by a new HP laptop that he tracked from Shanghai to Anchorage, then to Memphis, and finally to Boston. Sound familiar?

Remote, isolated, and largely dark for months at a time, it is hard to imagine why most companies shipping via air from Asia make a stop in Alaska... However, by applying calculus and their knowledge of great circles, FedEx found a way to increase the quantity of packages being delivered and by doing so increase revenue.

Most tech hardware, including the iPhone and iPad, that ships from the Original Design Manufacturers (ODMs) in and around Shanghai ends up in Anchorage where UPS and FedEx have built major logistical hubs to expedite customs. Anchorage is attractive to shippers because 90% of the industrialized northern hemisphere can be reached within 9.5 hours from Anchorage, allowing the carriers to transport more cargo and consume less fuel.

The intermediary stop in Anchorage, as opposed to flying from Shanghai to Oakland, CA, actually increases total flight distance by around 144 miles but allows the aircraft to carry an additional 45,000kg of cargo (instead of extra fuel) increasing revenue for the trip by around $90,000.

Anchorage's prime global location combined with the growth of China's tech exports have made Alaska's Ted Stevens International Airport (ANC) the number three airport in the world for cargo traffic, surpassing Tokyo. ANC currently ranks behind only Hong Kong and Memphis (the U.S. hub for Federal Express) in air cargo worldwide.