Astronomer.
Edmond Halley (8 November 1656 – 14 January 1742) was an English astronomer, geophysicist, mathematician, meteorologist, and physicist who is best known for computing the orbit of the eponymous Halley's Comet. He was the second Astronomer Royal in Britain, following in the footsteps of John Flamsteed.
Source: 1.) "It can hardly have been due to any reluctance on Newton's part to becoming too closely involved with Halley, the well-known atheist." Derek Gjertsen, The Newton Handbook (1986), page 250.