Where

A Grade II*-listed Georgian townhouse in Bath dating from 1764. The building is the former home of the 18th-century astronomer William Herschel and his sister Caroline, who acted as his assistant and became a noted astronomer in her own right.

Opened

1981.

What

“The museum is a tribute to the Herschels’ achievements as astronomers. It looks at the history of astronomy in the 18th century and its links to modern space technology,” says museum director Deborah James.

A musician by trade, William developed an interest in astronomy in his 30s and began building instruments to observe the stars. In 1781 he discovered the planet Uranus using a 7ft reflecting telescope of his own design that was in the back garden of the townhouse.

“The museum also depicts the social and musical atmosphere of Bath in the late-18th century,” says James, while the building and garden are fitted out to recreate an ordinary, middle-class residence from that period.

Collection

Astronomical paraphernalia from the late-18th to early-19th century, including telescopes, lenses and an onsite workshop where William built his instruments.

The museum also displays items from the Herschel family’s private collection, such as personal correspondence and notebooks containing original diagrams and observations; in one letter, Caroline describes her excitement at discovering a new comet.

A further room is devoted to 18th-century musical instruments and concert posters, while a film narrated by the astronomer Patrick Moore, the patron of the museum, runs in the underground auditorium.

Help at hand

A director, learning officer and manager make up the permanent staff. Additional help comes from weekend stewards and a team of about 30 volunteers.

Budget

The museum is financed independently. Trustees include the Bath Preservation Trust and the Royal Astronomical Society. Adult admission is £5.

Visits

8,000 in 2011.

Highlights

“Our most iconic object is the 7ft telescope. It’s an exact replica of the telescope [William] Herschel used to discover the planet,” says James.

Visitors also enjoy seeing a large brass orrery (a model of the solar system) built shortly after William’s discovery. A dress worn by Caroline is very popular. “People are always surprised by how small she was, ” says James.

Survival tip

“From our point of view, survival really depends on attracting new audiences,” James says. “Always give them something new to come back to.”

Sticky moment

“During one heritage open week we had a local press photographer taking pictures of a school visit,” says James. “He got a child to stand on a statue of the Herschels in the garden. Caroline is holding a quill in her hand and the child managed to snap it off.”

Future plans

A new exhibition space, the Caroline Lucretia Gallery, opened in September 2011. “It’s a very secure space and will allow us to have objects on display that are really very important,” says James. The space will host temporary exhibitions.

www.bath-preservation-trust.org.uk