Star Wars is often lampooned for getting physics wrong, most famously this quote from Episode IV, A New Hope:
You’ve never heard of the Millennium Falcon?…It’s the ship that made the Kessel Run in less than twelve parsecs.
— Han Solo
Yeah, yeah. We know. Parsecs are a unit of distance, not time. You nerd.
Admittedly, Han’s line from in A New Hope confuses the issue, because he was trying to persuade Obi-Wan that the Falcon is a fast ship.
But here’s the thing. Han referred to ‘parsecs’ correctly. He’s bragging that his ship is fast because its hyperdrive covers distance more efficiently than most.
I’ll break this down for you with two facts, smarty pants.
One. Traveling through hyperspace ain’t like dusting crops, boy. The fastest way from point A to point B through hyperspace is not a straight line. It is a vector carefully calculated to keep you safe while navigating around the gravitational wells of all the stars and other matter in proximity to your route. The vector is complicated by weird relativistic things that happen at faster-than-light speeds, which I don’t have time to explain to you right now.
Point is, the better your calculations are, the shorter your route is.
(Making these sophisticated calculations is the primary reason astromech droids like R2-D2 exist.)
Two. The Kessel Run involved a series of hyperspace jumps through a dense, dynamic star cluster. It was a region of space with twisted and dangerous routes thanks to a very high density of things to crash into and exert gravitational force on you. It was so dangerous that it couldn’t be effectively policed, making it ideal cover for smugglers transporting the illicit spice mined on Kessel.
Navigating the Kessel Run skillfully wasn’t about high velocity. It was about covering as little distance as you could. The shorter the distance you covered — that is, the fewer parsecs you traveled — the less your fuel you spent, the better your hyperspace engine’s speed and maneuverability, the better your skill as a pilot, and the greater your bragging rights.
See? Not a goof. Not a mistake.
Who’s the nerd now?