That’s not true either, it takes way more energy to drop your orbit the further out you are, regardless of eccentricity. It’s easier to curcularize near apoapsis, easier to change apoapsis and orbital planes at periapsis. The trick, however, is that bonus from periapsis works on being at any periapsis (ie, a near miss of a planet), just need the speed boost from being nearest the gravity well. That’s what gravitational slingshots are. I think a sun trajectory uses Jupiter a few times for maneuvers.
That’s not true either, it takes way more energy to drop your orbit the further out you are, regardless of eccentricity. It’s easier to curcularize near apoapsis, easier to change apoapsis and orbital planes at periapsis. The trick, however, is that bonus from periapsis works on being at any periapsis (ie, a near miss of a planet), just need the speed boost from being nearest the gravity well. That’s what gravitational slingshots are. I think a sun trajectory uses Jupiter a few times for maneuvers.