William Rutter Dawes

from Wikipedia, the free encyclopedia
William Rutter Dawes

William Rutter Dawes (born March 19, 1799 in London , † February 15, 1868 in Haddenham ) was an English astronomer and clergyman . In particular, he carried out observations of the planets and measurements of binary stars .

Live and act

Dawe's father was a math teacher interested in astronomy . Dawe's mother died very early. When his father accepted the post of governor of Sierra Leone , Dawes was first raised in Portsmouth by his grandfather . From 1807 he lived (apart from a two-year hiatus during which his father was in England) in the family of Reverend Thomas Scott , a well-known commentator on the Bible at the time .

Since his father had planned for him the career of a clergyman, Dawes first studied theology under Scott, but could not accept some doctrines of the Anglican Church . He therefore started studying medicine and practiced as a doctor after graduating. During this time he married Thomas Scott's widow, who was several years his senior. In 1826, after the death of his only sister, he settled in Liverpool . He turned back to religion and took over a small Anglican church in Ormskirk .

Dawes had a very keen interest in astronomy from childhood. His first telescope was a refractor with an aperture of only 4 cm, with which he made observations in Liverpool through an open window. In Ormskirk he set up his first observatory , which was equipped with a 9 cm refractor from Dolland. Due to his poor health, Dawes gave up his ward in 1839, accepted an offer from George Bishop and worked for four years at his observatory in Regents Park.

Dawes was considered one of the best observers of his time and was nicknamed "eagle eye" (in fact, Dawes was very nearsighted ). From 1831 to 1844, Dawes made the most accurate measurements of the positions of binary stars.

In 1842 he married for the second time - his first wife had died in Ormskirk several years earlier. Marriage to the wealthy widow of John Welsby, a lawyer in Ormskirk, brought financial independence. 1844 the couple moved to Cranbrook in the county of Kent . Here Dawes built his second observatory, which he equipped with a very good 6- inch (15 cm) refractor from Merz in Munich .

He had a close friendship with the astronomer John Herschel (the son of Wilhelm Herschel ), who lived with his family only a few kilometers from Cranbrook. He was also friends with William Lassell . On the night of September 18, 1848, when Lassell found the eighth moon of Saturn (later called Hyperion ), Dawes was visiting his observatory near Liverpool . Since Lassell discovered the faint little point first, he is considered to be the discoverer of the moon (together with the Americans William Cranch Bond and George Phillips Bond , who saw him on the same night).

In 1850 Dawes moved his observatory to Wateringbury, near Maidstone . In 1851 he discovered deep dark areas in the umber of sunspots . In 1852 he developed a special eyepiece that minimized the risk of observing the sun and enabled more detailed observations of the photosphere . In 1857 he moved to Hopefield near Haddenham near the Thames .

When his wife died in 1860, Dawes fell into deep depression and his health continued to deteriorate. For years he had had very severe headaches. Now presented asthma , heart problems and increasing deafness one. Dawes was only able to continue his observations to a very limited extent.

During the opposition of Mars in 1864, he made 27 detailed drawings of the planet. From these, Richard Anthony Proctor created one of the first maps of Mars, which was published in 1869.

Dawes died of apoplexy in 1868 and was buried in Haddenham Cemetery.


Dawes was accepted as a member of the Royal Astronomical Society in 1830 , which awarded him the gold medal of the Royal Astronomical Society in 1855 for his achievements . In 1865 he was accepted as a member (" Fellow ") in the Royal Society .

In his memory, an impact crater was named on the moon ( Dawes ) and one on Mars. Even today, William Rutter Dawes' name is also associated with the so-called Dawes criterion , in which he set up an empirical formula that specifies the smallest angular distance at which two stars can still be perceived as individual objects.


Web links