[elihu]

It seems kind of crazy that they would visit the Greeks, then do another flyby of Earth in order to visit the Trojans. I wonder what the cost-benefit analysis was of doing that versus just sending separate probes to each of those (which presumably would need a lot less fuel)?

Is this one of those things where this really is the best and cheapest option and my intuition of orbital mechanics is just wrong?

[wiml]

The flybys provide course changes for very little fuel, including pretty significant velocity boosts. It's not uncommon for a probe to spend a while ping-ponging around the inner system just to get enough speed to reach the outer planets. I doubt the probe has a whole lot of delta-v left once it leaves Earth the first time, probably just enough for course corrections so it can hit the flybys precisely.

[hinkley]

What ever happened to the interplanetary highway idea?