James Bradley (1692-1762) was born in Sherborne, Gloucestershire, and educated at Northleach grammar school and Balliol College, Oxford (B.A., 1714; M.A., 1717). He developed an interest in astronomy under the influence of his uncle James Pound, and assisted him in making observations. Two of Bradley's own observations were published in 'Philosophical Transactions of the Royal Society' in 1718, and later that year he became a fellow of the society. He was ordained in 1719, and became Vicar of Bridstow in Monmouthshire.

From 1719 to 1721, Bradley and Pound attempted to determine the parallax of the Sun from observations of Mars at opposition, and Bradley produced new tables for the phenomena of Jupiter's satellites. In 1721 he was appointed to the Savilian Chair of Astronomy at Oxford and resigned his church livings. Following a period of observational work at Kew and Wanstead, he presented a paper to the Royal Society in 1729 announcing the discovery of the 'aberration of light', an apparent shift in the position of stars caused by the movement of the Earth around the sun, and used his theory to calculate the speed of light.

Bradley was appointed Astronomer Royal in 1742. He began a rigorous observing programme in which he continued his research into the aberration of light. In 1748 he published a paper announcing the discovery of the nutation of the Earth, a nodding of the axis of rotation caused by the gravitational pull of the Moon. He was lecturer in experimental philosophy at Oxford, 1729-1760, and a member of the council of the Royal Society, 1752-1762. Bradley died at Chalford, Gloucestershire, on 13 July 1762. His observations were published in two volumes, 1798 and 1805.

Nathaniel Bliss (1700-1764) was born on 28 November 1700. He attended Pembroke College, Oxford (B.A., 1720; M.A., 1723), and became Rector of St Ebbe's, Oxford, in 1736. In 1742 he was appointed Savilian Professor of Geometry and Fellow of the Royal Society. That year he began to correspond with James Bradley, who he later assisted at the Royal Observatory. He replaced Bradley for the observation of the transit of Venus on 6 June 1761, and succeeded him as Astronomer Royal in 1762. Bliss died on 2 September 1764. The observations made under his supervision were published in 1805.