An astrolabe is a mechanical device that, prior to the development of the sextant, was widely used by mariners. Said to have been developed by Hipparchus, greatest of the ancient Greek astronomers (although some scholars give Ptolemy the honor), the astrolabe was used by astrologers when they erected horoscopes to determine the positions of the planets. (Prior to the development of ephemerides, it was necessary to actually look at the heavens when casting a horoscope.). The term astrolabe means “taking the star” in Greek, so it could be used to refer to any instrument for observing the stellar dome. Thus, in the early medieval period, astrolabe was often applied to the armillary sphere, a different instrument. The device now called an astrolabe is more properly termed a planispheric astrolabe. Originally Greek, this instrument was lost to western Europe until its reintroduction by Arabic sources.
a bay on the northeast coast of New Guinea (Maclay Coast). The bay is about 37 km long and 34 km wide, with depths of 40–106 m. The coast is hilly and covered with tropical vegetation. Many points on the coast have Russian names—for example, Konstantin Harbor, Cape Novosil’skii, Cape Koptev, and the Gogol River—as a result of the work done by the Russian traveler N. N. Miklukho-Maklai in New Guinea.