Thomas Pynchon's Mason & Dixon (1997)

Mason & Dixon

Joseph-Jérôme de Lalande

Provided by Doug Millison

From a (long-gone) Online Lalande Bio:

Joseph-Jérôme de Lalande (1732-1807) became director of Paris Observatory in 1795 and produced a catalog of nearly 50,000 star positions. Today his catalog is remembered mainly for the name it bequeathed to a lone 7th-magnitude star in Ursa Major.
Lalande 21185 can be seen on spring evenings glowing like a dim ember at magnitude 7.5 in the hind feet of Ursa Major. It is only 8.3 light-years away, a little closer than Sirius but 4,000 times fainter. With an absolute visual magnitude of 10.5 it emits only 1/180 the light of the Sun.

Although dim and obscure, Lalande 21185 has a history stretching back two centuries. It takes its name from French astronomer Joseph-Jérôme Lefrançais de Lalande, who included it in a star catalog that has since fallen into obscurity. A friend of Charles Messier and the author of several astronomy textbooks, Lalande was well known in his time not only for his writings but also for his love of publicity. Indeed, his activities extended well beyond astronomy. On one occasion, in order to convince the public not to fear spiders, he swallowed several of the eight-legged creatures. He hid royalist friends in the Paris Observatory during the French Revolution and made a balloon ascent at age 67.

To astronomers today Lalande is most infamous for a discovery he failed to make. In 1795, while working on his star catalog, either he or an assistant twice recorded Neptune -- but mistook it for a star, even though the planet's position on the second night differed from that on the first. This oversight was all the more remarkable in light of William Herschel's acclaimed discovery of the new planet Uranus 14 years earlier. Neptune would go unfound for another 51 years.

Lalande's star catalog, Histoire Céleste Française, was published in 1801. It contained nearly 50,000 stars. There seemed nothing special about number 21185. It was just another faint star in a catalog full of them, and for decades it attracted no attention.

--Ken Croswell is author of The Alchemy of the Heavens: Searching for Meaning in the Milky Way, a new popular-level book on our galaxy.


Mason & Dixon
Mason & Dixon - Thomas Pynchon