Edmond (or Edmund) Halley, FRS (pronounced ; 8 November [O.S. 29 October] 1656 – 25 January 1742 [O.S. 14 January 1741] ) was an English astronomer, geophysicist, mathematician, meteorologist, and physicist who is best known for computing the orbit of Halley's Comet. He was the second Astronomer Royal in Britain, succeeding John Flamsteed.
There was only one astronomer before him in the ARB
He was the second one, meaning there was only one before him.