Ursa Major is the name of a constellation comprising stars from the head and forelegs of Ursa Major; "pucwan" (ပုဇွန်) is a general term for a crustacean, such as prawn, shrimp, crab, lobster, etc. In Roman mythology, Jupiter (the king of the gods) lusts after a young woman named Callisto, a nymph of Diana. Juno, Jupiter's jealous wife, discovers that Callisto has a son named Arcas, and believes it is by Jupiter. Juno then transforms the beautiful Callisto into a bear so she no longer attracts Jupiter. Callisto, while in bear form, later encounters her son Arcas. Arcas almost shoots the bear,
HMS Ursa (R22) refitted for service in the Far East and joined the British Pacific Fleet where she served until 1945. She then returned to the United Kingdom and paid off in 1946. During the War "Ursa" was adopted by the Borough of Hendon as part of "Warship Week". The plaque from this adoption is held by the National Museum of the Royal Navy in Portsmouth. After the Second World War "Ursa" went into reserve at Portsmouth, transferring to the Chatham reserve in 1952. During 1953 and 1954 "Ursa" was converted to a Type 15 anti-submarine frigate with the new pennant number F200.