'Astrologer' was the British movement of two unescorted merchant ships from Gibraltar to Malta (12/15 November 1941).

In an attempted deception, the 5,649-ton Empire Defender and 6,463-ton Empire Pelican passed eastward through the Strait of Gibraltar independently on 12 and 14 November 1941, and followed the same pattern as Empire Guillemot in 'Propeller'. The undertaking was probably compromised, possibly from Axis awareness of an earlier attempt of this nature by the slow freighter Parracombe after her crew had been taken prisoner in North Africa, and/or from observation of the vessels' passage from the Spanish coast.

Empire Pelican and Empire Defender were attacked and sunk off the Galite islands group, on 14 and 15 November respectively, by Italian torpedo bombers. This setback concluded the attempts to succour Malta from the west for a full year. At Alexandria, the presence of the 3,338-ton Rodi, an Italian vessel captured and renamed as Empire Patrol, encouraged an attempt to pass stores from the east.

Late in 1942 the fuel situation in Malta became crucial as a result of the high tempo of operations by island-based aircraft in support of 'Torch'. Empire Patrol sailed on 1 November 1942 loaded with 1,200 tons of aviation petrol and 300 tons of benzine, all in drums, in an attempt to make an unescorted passage to Malta. The ship’s orders were to pass east of Cyprus into Turkish waters wearing Turkish colours, then to turn westward under Italian colours as if she were an Italian freighter bound from the Dardanelles to southern Italy, a commonly used route.

The commanding officer had total discretion to abandon the attempt if he was convinced that his disguise had been compromised. The ship was plagued with electrical and engine problems and, during the afternoon of 2 November, was closely examined by a German reconnaissance aeroplane. In consequence the attempt was abandoned and Empire Patrol entered the Cypriot port of Famagusta on 3 November.