The early 19th century had its own version of today's
dark matter problem: the planet Uranus was drifting
off course. The mystery was solved in 1846, when
observers, guided by theorists, discovered Neptune.
Its gravity could account for Uranus's wayward orbit.
Historians have traditionally apportioned credit between
a French theorist, Urbain Jean Joseph Le Verrier, and
an English one, John Couch Adams. Le Verrier's
role is undisputed, and so was Adams's--until the
Just as more historians were beginning to reexamine
Adams's role, a sheaf of crucial documents went
missing from a British archive. It surfaced in Chile
in 1998. The authors came across other crucial
documents this past summer.
The bottom line is that Adams did some interesting
calculations but deserves no credit for the discovery.