In 1781 William Herschel Identified Uranus as 7th planet
On March 13, 1781, William Herschel Identified Uranus as 7th planet, thus titillating students for centuries.
Until Herschel’s confirmation, it was thought there were 6 planets in orbit around the sun.
Uranus (part) and Miranda
from Astronomical Worlds series 4
Japan Post February 3, 2021
Designer: Maruyama Satoshi (丸山 智)
William Herschel observed a faint object in the constellation Gemini and noted that it moved slowly relative to the background stars. First thinking it a comet, Herschel later correctly identified it as a planet and wanted to name it after the monarch of his adopted United Kingdom. But astronomers decided to maintain the tradition of naming planets after mythological figures, and the seventh planet became known as Uranus. 240 Years Ago: Astronomer William Herschel Identifies Uranus as the Seventh Planet – NASA
Despite modern takes on the name Uranus, the planet was named after the primordial or origin god of the skies and heavens from Greek mythology. If Herschel had his way, the planet would have been called Georgium Sidus.
by Lemuel Francis Abbott
oil on canvas, 1785
NPG 98
Courtesy © National Portrait Gallery, London
Herschel directed the construction of a 40-foot reflecting telescope:
To prepare for the telescope, Herschel first insisted on moving to a larger estate in Slough, about 20 miles west of London. Herschel commissioned the casting of a 40-foot iron tube and the slab of speculum (an alloy of copper and tin) that would be polished into a mirror nearly 4 feet in diameter. He then oversaw construction of a gigantic rotating platform that would be used to reposition the telescope. Not surprisingly, the 5-year project went over budget. The king gave Herschel more money but not enough to complete the work. A Giant of Astronomy | Science History Institute
Herschel’s 40-foot reflecting telescope, completed in 1789.
At the time, was the largest and most expensive scientific instrument built.
Image courtesy A Giant of Astronomy | Science History Institute
Full sheet Astronomical Worlds series 4