The Royal Observatory Social and Sports Club was established in 1948 by observatory staff working at Herstmonceux Castle. The Club was open to all people working at Herstmonceux, with members paying a subscription to use club facilities and take part in activities. The name of the Club was changed to the Royal Greenwich Observatory Club (RGO Club) in 1959. The club was affiliated with the Civil Service Sports Council.

The Royal Observatory Hockey Club and the Lawn Tennis Club pre-date the RGO Club. These clubs were later merged into the central RGO Club, and their records were amalgamated into the collection before deposit.

A similar club had been established a year earlier, in 1947, at the Abinger Magnetic Observatory: the 'Royal Observatory Abinger Social and Sports Club' (ROASSC). In 1957 staff of the Time Department based at Abinger began to transfer to Herstmonceux, and the ROASSC was merged in to the RGO Club. The records of this club were added to the records of the RGO Club before deposit.

At first the RGO Club was managed by a central committee, but as its activities increased a system of "sections" was established. Each club activity had a section managed by officers elected at the club's annual general meetings.

The RGO Club originally had the use of space in the wartime huts in the grounds of Herstmonceux Castle, with occasional use of the castle ballroom. These spaces were used for indoor activities such as table tennis, snooker and billiards, darts, and ballroom and folk dancing. The huts were due to be demolished in 1957-58, and the Club began raising funds to construct a clubhouse. Work on building the clubhouse began in the spring of 1959. Money for the project was provided by club members and a loan from the Civil Service Sports Council. The majority of the building work was carried out by club members themselves. Construction of the clubhouse was paused in spring 1960 due to a dispute with the local council over planning permission; this was resolved and the building was completed in the summer. A formal opening ceremony took place on 01 October 1960. The clubhouse included table tennis and snooker tables, a lounge area, a bar, and dart board. A small shop was also run from the clubhouse by RGO Club members.

For outdoor activities, the hard tennis court, swimming pool, and sports field within the Castle grounds were brought into usable condition by Club volunteers. In the late 1950s a wooden sports pavilion was built by Club members in the corner of the sports field.

Club sporting activities included cricket, hockey, stoolball, table tennis, and tennis, with players and teams from the RGO Club sometimes competing in local leagues. The Club organised an annual tournament, the Spencer Jones Indoor Sports Trophy, which included billiards, snooker, table tennis, darts, and later chess. From 1968 the Club participated in the Science Research Council (later Science and Engineering Research Council) annual sports days.

The social activities of the club included dances and discos, visits to local attractions, dinners, film showings, and talks. There was an annual pantomime, written and performed by Club members, as well as a Christmas party for children of Observatory staff.

In the 1980s some RGO staff transferred to the Roque de los Muchachos Observatory on La Palma, Canary Islands. A branch of the RGO Club was established on La Palma in the later part of the decade, but there are few records about the La Palma club within the collection.

In the late 1980s, as the Royal Observatory at Hestmonceux prepared for relocation to Cambridge, members of the RGO Club were involved in negotiating for the provision of sports and social facilities at the new site. A workshop building on the new site at Madingley Road in Cambridge was fitted out as a clubhouse with a bar, lounge, and space for activities.

The RGO Club was disbanded when the Observatory closed in 1998.