Science News / Accidental Astrophysicists:

Dmitry Khavinson and Genevra Neumann didn’t know anything about astrophysics. They were just doing mathematics, like they always do, following their curiosity. In 2004, they posted a new result, an extension of the fundamental theorem of algebra, on MathSciNet, a preprint server.

Five days later, they received an e-mail. Congratulations, it said. You just proved Sun Hong Rhie’s conjecture on gravitational lensing.