William Ball (or Balle, 1631–1690) was an

English English usually refers to: * English language * English people English may also refer to: Peoples, culture, and language * ''English'', an adjective for something of, from, or related to England ** English national ide ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

. He was one of the founding Fellows of the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

. He was appointed the Society's first treasurer on 28 November 1660, and served until 1663. He was the eldest son of Sir Peter Ball and his wife Anne Cooke, daughter of William Cooke. He became an ardent astronomer, and he gained ownership of a twelve-foot telescope. In 1655, when the

Rings of Saturn The rings of Saturn are the most extensive ring system of any planet in the Solar System. They consist of countless small particles, ranging in size from micrometers to meters, that orbit around Saturn. The ring particles are made almost entir ...

had apparently disappeared due to being seen edge-on from Earth, Ball and his brother

Peter Peter may refer to: People * List of people named Peter, a list of people and fictional characters with the given name * Peter (given name) ** Saint Peter (died 60s), apostle of Jesus, leader of the early Christian Church * Peter (surname), a sur ...

observed them as a band (or "fascia") upon the planet. The same year he established the rotation rate of the planet Saturn. In 1660 he fell 30 feet onto hard ground. This accident left him in continual ill health. In 1666 he retired to his estate in Devon and in 1668 married Mary Posthuma Hussey, they raised six children. Managing his family's estate together with its distance from London left little time to follow his scientific interests. In a summary of Ball's observations of Saturn in 1665, his colleague

Robert Moray Sir Robert Moray (alternative spellings: Murrey, Murray) FRS (1608 or 1609 – 4 July 1673) was a Scottish soldier, statesman, diplomat, judge, spy, and natural philosopher. He was well known to Charles I and Charles II, and to the French ...

remarked that there appeared "not ''one'' body of a Circular Figure, that embraces his Disk, but ''two''". This cryptic remark resulted in the mid-19th century in a claim that Ball had observed what is now known as the Cassini Division in

Saturn's rings The rings of Saturn are the most extensive ring system of any planet in the Solar System. They consist of countless small particles, ranging in size from micrometers to meters, that orbit around Saturn. The ring particles are made almost entire ...

, ten years before Cassini did himself, and that the feature should more correctly be known as "Ball's Division". 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. The crater Ball on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

was named after him.

References

{{DEFAULTSORT:Ball, William 1627 births 1690 deaths 17th-century English astronomers Founder Fellows of the Royal Society