Discovery of Neptune

The planet Neptune is a planet which has been claimed to have been discovered through mathematics alone. Discussions on this topic revolve around a claim that the position of Neptune was predicted and discovered through Newton's Laws of Gravitation, and that it is therefore a confirmation of Newton's theory.

Writer and astronomer Jeffrey Bennett (bio) describes this claim (Archive):

Perturbation Theory
According to various sources we find that Neptune was discovered on the basis of Perturbation Theory.

https://www.encyclopediaofmath.org/index.php/Perturbation_theory (Archive)

From Perturbation Theory in Celestial Mechanics (Archive) by Dr. Alessandra Celletti we read:

https://en.wikipedia.org/wiki/Urbain_Le_Verrier

In describing the perturbation method, the Wikipedia article Discovery of Neptune (Archive) describes:

This is, of course, exactly opposite of using a mathematical model to predict.

See Astronomical Prediction Based on Patterns for further information on Perturbation Theory.

Pre-Discovery Observations
Curiously, according to a depiction of its discovery it is described that Neptune was "pre-discovered" and that these observations were "important in accurately determining the orbit of Neptune."

https://en.wikipedia.org/wiki/Discovery_of_Neptune (Archive)

Discovered By Luck
Other sources tell us that the planet was discovered by luck, rather than the reliability of any mathematical model.

https://earthsky.org/human-world/today-in-science-discovery-of-neptune (Archive)

http://www.helas.gr/conf/2011/posters/S_5/dallas.pdf (Archive)

https://www.oddsalon.com/jan-2-1860-the-discovery-of-planet-vulcan/ (Archive)

From an essay Leverrier: The Zenith and Nadir of Newtonian Mechanics (Archive) by philosopher of science Norwood Russell Hanson (bio):

Dishonesty
Science historian Nicholas Kollerstrom states that dishonesty was involved with this claim.

https://en.m.wikipedia.org/wiki/Discovery_of_Neptune (Archive)

American Journal of Science and Arts
From Vol IV of the American Journal of Science and Arts, November, 1847, we read the following (Archive) from astronomer Sears C. Walker:

Earth Not a Globe
Samuel Rowbotham devotes space to the discovery of Neptune in Earth Not a Globe:

THE PLANET NEPTUNE

Footnotes


 * 1 "Illustrated London Almanack" for 1847.
 * 2 "Times" Newspaper of Monday, September 18, 1848.
 * 3 "Cosmos," by Humboldt, p. 75.
 * 4 "How to Observe the Heavens," by Dr. Lardner, p. 173.

The Planet Vulcan
Le Verrier later went on to "discover" the planet Vulcan with his same methods: