Royal Observatory South Building

The Royal Observatory South Building, constructed between 1892 and 1899 by William Crisp in collaboration with W H M Christie, the Astronomer Royal, originally served as the New Physical Observatory for the Royal Greenwich Observatory and is now used as offices and a planetarium. The building features banded brick and Doulton terracotta with a slate roof that rises to a central flat area adorned with decorative iron railings. It has a cruciform plan with two storeys and attics, situated on a steeply sloping site, and includes a central copper dome designed to accommodate the Lassell Dome telescope.

The central core of the building has a single-bay canted front on each side, with two-bay wings that project and terminate in paired stacks. Designed in a Germano-Italianate Renaissance style, the ground floor showcases Gibbsian surrounds and keystones around wooden casement windows, while the first floor features heavy sill bands with de Vriesian pilasters, mullions, and transoms. Aediculed dormers with pediments are present, and the north side of the central section has a double-height arrangement of mullions and transoms with decorative panels in between and below.

The principal entrance is located on the first floor at the end of the eastern arm, accessible via six steps, and consists of a double door set beneath a round-headed opening, flanked by pilasters. Above this entrance is a balcony with a pedimented dormer behind. The building is adorned with numerous decorative plaques and shields created by Doultons, including a plaque above each first-floor window dedicated to significant British scientists and astronomers. The central window features a plaque for Isaac Newton, while those at the ends of the wings honor Flamsteed, Bradley, Maskelyne, and Airy, which are considered the most prestigious positions. A bust of John Flamsteed, the first Astronomer Royal, sculpted by J Raymond Smith around 1898-1899, is also present. The South Building was specifically designed to house the Lassell Dome telescope and support the Royal Observatory's groundbreaking work in astronomical photography, and it later accommodated two 'Thompson equatorial' telescopes. The building's impressive terracotta detailing exemplifies the material at its finest.