In sci.space.history Pat Flannery wrote:
Since Juno has three very large solar arrays on it to give
sufficient electrical power via sunlight (rather than RTGs) at
Jupiter's distance from the Sun, why wasn't it equipped with an ion
engine to cut its trip time down some? The arrays would generate
lots of power while it's in the inner solar system, as it will be
for a lot of time till the Earth encounter in October of 2013
slingshots it out to Jupiter:

Concerns about added complexity?

How close was Juno to an Atlas V 551 configuration's mass limits?

rick jones
--
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