Navy Ten Nautical Miler United States Navy a premiere foot race to replace the disestablished Blue Angels Marathon. The length of ten nautical miles was chosen as the length because it is roughly the distance from the shore to the horizon when viewed at sea level. It was also the distance traveled by the Allied Forces on D-Day, significant because the inaugural run of the Navy Ten Nautical Miler took place on June 6, 2010, the anniversary of D-Day. A nautical mile is approximately the distance of one minute of arc of latitude on the Earth's surface. Sailors throughout history have used this form
Longitude then the longitude at a point would be equal to the angle between a vertical north–south plane through that point and the plane of the Greenwich meridian. Everywhere on Earth the vertical north–south plane would contain the Earth's axis. But the Earth is not radially homogeneous and has rugged terrain, which affect gravity and so can shift the vertical plane away from the Earth's axis. The vertical north–south plane still intersects the plane of the Greenwich meridian at some angle; that angle is the astronomical longitude, calculated from star observations. The longitude shown on maps and GPS devices is the