#OTD in 1846.
Astronomers Urbain Le Verrier, John Couch Adams and Johann Gottfried Galle collaborate on the discovery of Neptune.
There is evidence that Neptune was seen and recorded by Galileo Galilei in 1613, Jérôme Lalande in 1795, and John Herschel in 1830, but none are known to have recognized it as a planet at the time.
https://en.wikipedia.org/wiki/Discovery_of_Neptune
Neptune at PG:
https://www.gutenberg.org/ebooks/search/?query=neptune&submit_search=Search