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Columbus's Method of Determining Longitude: An Analytical View

Published online by Cambridge University Press:  21 October 2009

Keith Pickering
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Extract

On 14 September 1494, Christopher Columbus observed a lunar eclipse while at the island of Saona near the eastern tip of Hispaniola. He later recorded in his Libro de las Profecias that, from his timing of the eclipse, he determined his longitude to be ‘five hours and more than one half’west of Cape San Vicente. His actual longitude was three hours and 59 minutes west of Cape San Vicente, so Columbus was off by over an hour and a half, some 23 degrees of longitude.

Keywords

1. History.2. Astronomical navigation.
Type
Research Article
Information
The Journal of Navigation , Volume 49 , Issue 1 , January 1996 , pp. 95 - 111
Copyright
Copyright © The Royal Institute of Navigation 1996

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References

REFERENCES

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31 By coincidence, two of Molander's correlation successes occur below the horizon.Google Scholar
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