[1] The mounting is older however and dates to the 1850s, having been designed by Royal Observatory director George Airy and the firm Ransomes and Simms.

[4] The telescope was re-commissioned by Queen Elizabeth II in May 1975 after it was brought back from Herstmonceux in Sussex.

[6] The 28-inch telescope was installed on the same mounting as an older 12.8 inch aperture refractor at the same location.

[7] The telescope's objective lens was removed during the Second World War for safekeeping, and then put back after that conflict was over.

[2][3] The return of the 28-inch refractor in 1971 to the Greenwich Observatory site was featured in an episode of the British television show The Sky at Night.

[8] The telescope is known as the largest aperture refractor in the United Kingdom, and is a popular tourist attraction.

[11] In the early 21st century the telescope was normally free to visit, and could reached by going through a gift shop at the observatory when the facilities were open.

[12] However, it was also featured in an edutainment presentation called Great Equatorial Encounter and that experience cost the price of few pounds' currency.

[12] The mounting was designed by George Airy in the 1850s, for the older 13-inch refractor, in conjunction with the firm Ransomes and Simms.

[1] Originally it was rotated by a clockwork drive powered by water, and later in the 20th century this was replaced by electric motor driven system.

Two important figures for telescopes are the aperture and focal length, which affect the equations that describe their properties of magnification.

[5] The entrance door to the telescope is also noted for being made of iron, in the Victorian style.

[18] Between 1960 and 1963 over 1300 observations of 233 double stars were conducted with the filar micrometer from Herstmonceux with the 28 inch.