On this day in 1809 – April 4th – American astronomer and mathematician Benjamin Peirce was born in Salem, Massachusetts.

He graduated from Harvard University where he also obtained his M.A.. Peirce was appointed Harvard’s first Perkins Professor of Mathematics and Astronomy. He played a key role in the development of the Harvard College Observatory and carried out a great deal of important observational work, including helping to determine the orbital path of the newly discovered planet Neptune.