Kerbal Space Program

Planetary or moon encounters aren't showing if the game thinks there is a different close encounter sooner.

I discovered this bug during a recent trip to Gilly.I was following a few online guides showing how to get an easy encounter with Gilly, notably Matt Lowne's guides. I had planned to capture at Eve in a highly elliptical orbit, then raise my periapsis so it intersected with Gilly's orbit, then at periapsis burn retrograde a bit so that I'd get an encounter. This "easy" encounter refused to show and I spent quite awhile trying to figure out what seemed to be an easy idea, until I by happenstance added another maneuver node past the "close encounter" which then showed my intended close encounter. I also experienced this when returning to Kerbin. This problem is also not just inherent to the maneuver nodes, but also to the actual trajectory, and I didn't see my Gilly encounter appear until a third of my way through my orbit.

My game this happened in originally is modded, so I used my other computer to install a clean version of KSP and the identical thing happened. I'm going to link to a video showing the bug, this video will be using my modded install, but note that the bug appears to be in stock KSP too.

Workaround: Add another maneuver node past the first encounter that the game shows.
Despite this workaround showing the encounter, it is difficult to tell if an encounter has actually been achieved, and makes fine-tuning it difficult.

Bug in action: https://www.youtube.com/watch?v=st-rQg1L2-g