William Rutter Dawes

Alex Kiefer

Mr. Percival

Astronomy

11 Jan 2011

William Dawes

        William Rutter Dawes was born March 19 1799 and died February 15 1868. He was British, born in London and raised in West Sussex. He was named after his father, who was a mathematics teacher. His father wanted him to be a clergyman in the Church of England, but Rutter Dawes opted instead to be a physician.

        Dawes’ interest in astronomy began when he met William Lassell upon moving to Liverpool in 1826. He wrote a letter to John Herschel explaining how he used a 1.6 inch refractor, Flamsteed’s Atlas and Rees’s Encyclopedia to draw diagrams of all known binary stars. In 1829, he took up astronomy as a profession after observing with Lassell. He also became a friend and apprentice of John Herschel. Dawes upgraded Herschel’s telescope to a 3.8 inch Dolland refractor which greatly improved the resolution for identifying binary stars. Dawes thus earned the nickname “eagle eye Dawes.” Dawes was elected a fellow of the Royal Astronomical Society in 1830.

        Dawes was influenced to return to religion by Rev. Thomas Waffles of the Independent Chapel on Great George Street in London. Dawes led his own congregation in Ormskirk. But when his wife died in 1839, he renounced his own congregation and joined that of George Bishop in London. Bishop’s observatory had a 7 inch refractor telescope, which Dawes used freely until 1844. He married a rich woman in 1842, and built his own personal observatory with a 6.5 inch Merz refractor. He discovered Saturn’s crepe ring along with W.C. Bond, but the latter worked at Harvard and his news didn’t cross the Atlantic before Dawes announced his discovery. Lassell attempted to observe the crepe ring with his 24 inch reflector, to no avail. However, when he visited Dawes and used the 7 inch refractor, making it out in a few minutes.

        After winning the RAS’s Gold Medal in 1855, he moved to Haddenham in 1857 and provided free medical service to its residents. His second wife died in 1860, and he observed until 1865, making drawings of Mars during its opposition in 1864. In 1867, Richard Proctor made a map of Mars based on them. He was elected a Fellow of the Royal Society, and died 4 years later.

        Dawes’s legacy consists of multiple craters on Mars and the moon and a gap in Saturn’s C ring which are named after him. Also, the Dawes limit, a formula used to calculate the resolving power of a telescope, is named after him because of its importance in observing binary stars, a focus of Dawes’s.

Works Cited

Oates, Michael. "William Rutter Dawes (1799 - 1868)." The Home of Amateur Astronomy in the UK. 30 Nov. 2009. Web. 11 Jan. 2011. <http://www.mikeoates.org/astro-history/dawes.htm>.

"William Rutter Dawes." Wikipedia, the Free Encyclopedia. 8 Sept. 2010. Web. 11 Jan. 2011. <http://en.wikipedia.org/wiki/William_Rutter_Dawes>.