Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-10T11:16:42.611Z Has data issue: false hasContentIssue false
  • English
  • Français

Sphere to Spheroid Comparisons

Published online by Cambridge University Press:  23 August 2006

Michael A. Earle
Michael A. Earle
Affiliation:
Email: michael.earle@sympatico.ca
Get access Rights & Permissions [Opens in a new window]

Extract

The notion of the earth as a perfect sphere has served navigators quite well over the centuries and it continues to provide a basis for instruction and practical navigation. Aside from the fact that modern navigators employ refined models of the earth such as the WGS84 ellipsoid, which together with satellite positioning gives unprecedented positioning accuracy, the question arises as to just how good are the spherical results for distance when compared to the results for distance obtained from the spheroidal model. In this document a comparison is made of great circle distance (GCD) on the sphere with great ellipse distance (GED) on the spheroid. This comparison is then repeated for rhumbline distances. In each case it is concluded that the difference in using the sphere when compared to the spheroid is near 0·5%.

Type
Research Article
Information
The Journal of Navigation , Volume 59 , Issue 3 , September 2006 , pp. 491 - 496
Copyright
Copyright © The Royal Institute of Navigation 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1] Snyder, J. P. Map Projections-A Working Manual. Professional Paper. No.1395. Pub. U.S. Geological SurveyGoogle Scholar
[2] Earle, M. A. A Comment on Navigation Instruction The Journal of Navigation, 58, 337–340CrossRefGoogle Scholar
[3] Walwyn, P. R. The Great Ellipse Solution for Distances and Headings to Steer between Waypoints. The Journal of Navigation, 52, 421–424.CrossRefGoogle Scholar
[4] Williams, R. Geometry of Navigation, Ch.7. Horwood Publishing. ISBN. 1-898563-46-2.Google Scholar