While December 21 may be Chester Greenwood Day in Farmington Maine, it was on this day in 1877 that Chester patented earmuffs! According to Wikipedia Greenwood:
invented the earmuff in 1873, at the age of 15.[1] He reportedly came up with the idea while ice skating, and had his grandmother sew tufts of fur between loops of wire.[2] His patent was for improved ear protectors. He manufactured these ear protectors, providing jobs for people in the Farmington area, for nearly 60 years.[1] Read More
Also on this date in 1781, Sir William Herschel discovered Uranus. But the discovery of Uranus is not all that Herschel accomplished in his life he also:
….became famous for his discovery of the planet Uranus, along with two of its major moons (Titania and Oberon), and also discovered two moons of Saturn. In addition, he was the first person to discover the existence of infrared radiation. He is also known for the twenty-four symphonies that he composed.
NGC 2683 is an unbarred spiral galaxy discovered by William Herschel on February 5, 1788.
From 1782 to 1802, and most intensively from 1783 to 1790, Herschel conducted systematic surveys in search of “deep sky” or nonstellar objects with two 20-foot focal length (610 cm), 12-inch aperture (30 cm) and 18.7-inch aperture (47 cm) telescopes (in combination with his favoured 6-inch aperture instrument). Excluding duplicated and “lost” entries, Herschel ultimately discovered over 2400 objects defined by him as nebulae. (At that time, nebula was the generic term for any visually extended or diffuse astronomical object, including galaxies beyond the Milky Way, until galaxies were confirmed as extragalactic systems by Edwin Hubble in 1924.)
The 40-foot (12 m) telescope
During the course of his career, he constructed more than four hundred telescopes. The largest and most famous of these was a reflecting telescope with a 491⁄2-inch-diameter (1.26 m) primary mirror and a 40-foot (12 m) focal length. Because of the poor reflectivity of the speculum mirrors of that day, Herschel eliminated the small diagonal mirror of a standard newtonian reflector from his design and tilted his primary mirror so he could view the formed image directly. This design has come to be called the Herschelian telescope. On 28 August 1789, his first night of observation using this instrument, he discovered a new moon of Saturn.
A second moon followed within the first month of observation. The “40-foot telescope” proved very cumbersome, however, and most of his observations were done with a smaller 18.5-inch (47 cm) 20-foot-focal-length (6.1 m) reflector. Herschel discovered that unfilled telescope apertures can be used to obtain high angular resolution, something which became the essential basis for interferometric imaging in astronomy (in particular Aperture Masking Interferometry and hypertelescopes).
In his later career, Herschel discovered two moons of Saturn, Mimas and Enceladus; as well as two moons of Uranus, Titania and Oberon. He did not give these moons their names; they were named by his son John in 1847 and 1852, respectively, well after his death.
In 2007 evidence was cited by Dr. Stuart Eves that Herschel might have discovered rings around Uranus.[14]
Herschel measured the axial tilt of the planet Mars and discovered that the martian ice caps, first observed by Giovanni Domenico Cassini (1666) and Christiaan Huygens (1672), changed size with the planet’s seasons.
From studying the proper motion of stars, he was the first to realise that the solar system is moving through space, and he determined the approximate direction of that movement. He also studied the structure of the Milky Way and concluded that it was in the shape of a disk.
He also coined the word “asteroid”, meaning star-like (from the Greek asteroeides, aster “star” + -eidos “form, shape”), in 1802 (shortly after Olbers discovered the second minor planet, 2 Pallas, in late March of the same year), to describe the star-like appearance of the small moons of the giant planets and of the minor planets; the planets all show discs, by comparison. However, it was not until the 1850s that ‘asteroid’ became a standard term for describing certain minor planets Full Biography
Geesh! after reading about Herschel’s accomplishments I bet old Chester Greenwood would feel like B.D. in this old Doonesbury cartoon – I know I do!
