William Ball (astronomer)

William Ball (or Balle, "c." 1627–1690) was an English astronomer. He was one of the founding Fellows of the Royal Society. He was appointed the Society's first treasurer on 28 November 1660, and served until 1663. [cite journal
last = Maddison | first = R. E. W.
title=The Accompt of William Balle from 28 November 1660 to 11 September 1663
journal=Notes and Records of the Royal Society of London
year=1960 | volume=14 | issue=2 | pages=174–183
doi=10.1098/rsnr.1960.0030 ]

He was born to Sir Peter Ball, most likely in 1627. At some point he became an ardent astronomer, and he gained ownership of a twelve-foot telescope. In 1655, when the Rings of Saturn had apparently disappeared due to being seen edge-on from Earth, Ball observed them as a band (or "fascia") upon the planet. The same year he established the rotation rate of the planet Saturn.cite journal
last = Armitage | first = Angus
title=William Ball. F.R.S. (1627-1690)
journal=Notes and Records of the Royal Society of London
year=1960 | volume=15 | pages=167–172
doi=10.1098/rsnr.1960.0016 ]

In a summary of Ball's observations of Saturn in 1665, his colleague Robert Moray remarked that there appeared "not "one" body of a Circular Figure, that embraces his Disk, but "two".". This cryptic remark resulted in the mid-1800s in a claim that Ball had observed what is now known as the Cassini Division in Saturn's rings, ten years before Cassini did himself, and that the feature should more correctly be known as "Ball's Division". [e.g., Kirkwood (1871), "On the Formation and Primitive Structure of the Solar System," "Proceedings of the American Philosophical Society", pp.163-167.] However, actual examination of Ball's drawings of his observations does not support this claim. [C. Leeson Prince (1882), "Saturn's Ring" (letter to the editor), "The Astronomical Register", v.XX, pp.257-261.]

Ball crater on the Moon was named after his work.

References