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Eleven years after its perihelion, comet C/1995 O1 (Hale-Bopp) is stillactive. Between October 20--22, 2007, we detected a diffuse coma of 180x10^3$kmin diameter with a slight elongation toward N/S direction. The integratedbrightness was 20.04 mag in R_C, implying Af\rho=300 m and albedo x dustsurface $a_RC$=4300 km^2. The coma was relatively red at V-R=0.66 mag, which isconsistent with that of the dust in other comets. The observed properties andthe overall fading in brightness between 10 AU and 26 AU follow the predictedbehaviour of CO-driven activity (Capria et al. 2002). This is the most distantcometary activity ever observed.

Cometary activity at 25.7 AU: Hale--Bopp 11 years after perihelion