Voyager observations of interplanetary shocks

Data from Voyager 2 are used to compile a shock catalogue covering the 27 years of Voyager 2 solar wind data through the end of 2004. This catalogue is used to investigate the characteristics of shocks as a function of distance out to 75 AU. The shock occurrence frequency decreases with distance. Reverse shocks are most prevalent between 3 and 10 AU. The shock speed is solar cycle dependent with the highest speeds just after solar maxima. Shock strengths decrease with distance but do not show a strong solar cycle dependence. In the outer heliosphere shocks are often associated with merged interaction regions. As in the inner heliosphere, the relationship between the shocks and energetic particle fluxes is highly variable, with no apparent acceleration at some shocks and strong acceleration at others.