James Bradley

Bradley discovered stellar aberration in 1728, which provided the first direct empirical evidence of the Earth's orbital motion around the Sun. This finding effectively settled the lingering scientific debate over heliocentrism that had persisted since Copernicus.

In 1742, he succeeded Edmond Halley as the third Astronomer Royal of Great Britain. He held this prestigious post at the Royal Greenwich Observatory until his death in 1762.

He was actually trying to measure stellar parallax when he noticed an unexpected apparent motion in the star Gamma Draconis. He deduced that this motion was caused by the combination of the finite speed of light and the Earth's orbital velocity.

Yes, he also discovered the nutation of the Earth's axis, announcing his findings in 1748. This discovery further refined astronomical observation by explaining a complex, 18.6-year wobble in the Earth's rotation caused by gravitational forces.