The quotation from 17th century Liverpool astronomer Jeremiah Horrocks, that Hathaway shares with Lewis and Isobel Crompton in the canal boat, is inscribed on the base of a monumental (in both senses) telescope next to the Mersey Ferries terminal in Liverpool: "Thy return posterity shall witness; years must roll away but then at length the splendid sight again shall greet our distant children's eyes."
This episode features the music of Holst who was born in Cheltenham as was Robert Hardy who plays Sir Arnold Raeburn.
The most recent transits of Venus were in 2004 and 2012. The next ones will be 2117 and 2125.