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This report describes and analyses the observations of the brighter or more interesting comets discovered or at perihelion during 2011, concentrating on those with visual observations. Magnitude parameters are given for all comets with observations. Any evolution in the magnitude parameters of those periodic comets with multiple returns is discussed. Additional information on the comets discussed here and on other comets seen or at perihelion during the year may be found on the Section visual observations web pages.

By embracing 21st century design technology, the dialyte telescope concept now offers apochromatic performance using inexpensive glass types, with the benefits of low cost, very light weight, rapid cool-down times, and atmospheric dispersion control. Much larger apertures than with traditional technologies are now feasible.

During 2003-’04, with Saturn at perihelion, the rings were fully open upon the south face allowing excellent views of the southern hemisphere and up to 12 belts. Since 2002-’03 there had been an obvious darkening of the S. Polar Region, though the existing lighter area in the centre of the S. Polar Cap had become more conspicuous. Spot activity was noted over a wide range of latitudes from the N. edge of the S. Polar Cap to the southern Equatorial Zone. The occultation of the star SAO 78867 by the rings and globe was witnessed by several observers in the UK and USA.