Berlin banker and brother of the composer Meyerbeer, who set up a private observatory equipped with a 9.5-centimeter refractor. In collaboration with Johann H. Mädler, he produced, in 1830, the first accurate lunar map (Mappa Selenographica) and a companion descriptive volume (Der Mond), describing the surface features. These showed the Moon to be a world very unlike the Earth and contradicted the pro-selenite claims of Gruithuisen and William Herschel (see Moon, life on). Beer and Mädler's map remained the best available for several decades and helped persuade most professional astronomers that the Moon is uninhabited. The two also collaborated in the production of the first systematic chart of the surface of Mars.
