01
Great circles
The shortest path between two points on a sphere lies along a great circle — a circle whose center is also Earth's center.
Globe Curiosities · New York → Tokyo
New York to Tokyo: Why the Shortest Route Looks Curved
The New York to Tokyo shortest path does not look straight on a flat map. It bends north across the Pacific — because the shortest line across a sphere and the straightest-looking line on a flat map are not the same thing.
10,852 km
Shortest path on Earth
12,797 km
Straight-looking comparison
1,945 km
Approximate difference
Loading Earth…
Drag the Earth to rotate · cyan arc = shortest route
Earth is round.
The map is not.
On a globe, the shortest connection between two places follows what geographers call a great-circle route. Imagine slicing Earth through its center so that New York and Tokyo sit on the edge of the same enormous circle. The shorter section of that circle is the direct path across Earth's surface.
Put that spherical path onto a flat rectangular map and it no longer looks straight. It appears to bow toward the north. Nothing strange happened to the route. The distortion happened when a curved planet was flattened.
That is why a route from New York to Tokyo can look like it is taking a detour toward Alaska even when it is following the shortest geographic path.
A curve on the map can be the straightest
way across the planet.
Same Earth · Different intuition
The flat map changes what “straight” looks like.
The cyan route follows the great-circle path. The dashed route represents the tempting straight-looking alternative on a flat world map.
New York → Tokyo
Pacific-centered comparison
Shortest path on Earth
Straight-looking flat-map route
Shortest path on Earth
10,852 km
Straight-looking comparison
12,797 km
Approximate difference
1,945 km
A flat world map has to distort something.
Earth is approximately spherical, but most maps are rectangles. Transforming one shape into the other requires a map projection. Every projection preserves some geographic properties better than others and distorts something else — such as area, shape, direction or distance.
That distortion becomes especially noticeable on long east–west journeys at northern latitudes. New York and Tokyo look almost horizontally separated on many familiar maps, so our eyes expect a nearly horizontal path between them.
On the globe, however, the geometry is different. The shortest surface route rises toward Alaska and the North Pacific before descending toward Japan.
02
Map projection
Flattening Earth changes how long-distance geometry appears, so a route that is direct on the globe can look curved on paper.
03
Visual intuition
We learn geography from flat maps, so our eyes often interpret “straight on the map” as “shortest on Earth.” They are not always the same.
About the numbers
What exactly are we comparing?
The 10,852 km figure represents the approximate great-circle distance between reference points in New York and Tokyo. It is the shortest surface path in the spherical model used for this visualization.
The 12,797 km comparison represents the straight-looking flat-map alternative shown here using the same endpoints. The purpose is to demonstrate how strongly a flat-map intuition can differ from spherical geometry.
Real commercial flights do not necessarily follow either line exactly. Weather, winds, airspace restrictions, traffic, operational requirements and the precise airports used can all change an actual flight path.
Distances are approximate and are intended
as a geographic visualization rather than
an airline routing calculation.
Small differences are possible depending on
the exact reference coordinates and Earth
model used.