Sample H₂O maser images of U Her from February 1990 covering the velocity range between −16 and −14 km s⁻¹ with the strongest emission. The synthesised FWHM beam size (major axis: 0.″09; minor axis: 0.″08; position angle of the major axis: 71^◦) is shown in the left panel (−15.9 km s⁻¹). The images are oriented along right ascension and declination and the angular scales are relative to the position α = 16^h25^m47^s.39, δ = +18^◦ 53′ 32.9″ (J2000). Brightness contours are −0.25 (dashed contour), 0.25, 2.5, 5, 50, and 150 Jy per beam area (1.4 10⁻¹³ sr).