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Daniel Prates

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  1. Daniel Prates's post in How to do precision landing? was marked as the answer   
    With an atmosphere everyting gets more complicated. But I assume you want to land near a mun/minmus base. A good simple method is to do this:
    1. Go into a low orbit. The less excentric,  the better.
    2. Use normal or antinormal burns to get your orbit to pass directly above your target.
    3. Plan a retrograde maneuver node. Watch as its predicted path hits the ground.
    4. Move the node, foward or backwards so that it lands directly above your target.
    5. Execute? Well,  not yet. The tricky business is to counter the movement of your target,  since it is in the surface of a moving planet or moon. So place the end of the orbit beyond your target (how much is a matter of experience). Then execute the maneuver.
    6. Watch as you descend, and monitor your path and your target's position, as both you move and the target moves foward on the ground. Then tweak it little by little with more short retro burns. Your target moves a little,  you burn a little and so on. This will work if you left room to maneuver ahead of you,  viz,  your end path lying further from your target (because burning retrograde will always shorten the distance of your orbit's end).
    7. When you pass directly above your target,  point retro in relation to the SURFACE (and not 'orbit') and kill your speed completelly. You will then hover slowly towards your destination,  just control your descent speed. But only do this when close enough: do it prematurelly,  and the target will keep moving foward as you slowly fall towards the surface. 
    Now, also consider this: 
    1. You under-shot and now your orbit ends on the ground short of the target?  Burn RADIAL. It will throw your orbit end further,  without changing speeds.
    2. Is your target a little to the side of your path?  Tweak with small  normal or antinormal burns.
    3. I always build surface outposts as close to the equator as I can. It will make me worry with only one axis of displacement,  viz,  I will start from an equatorial orbit and only worry about how far/ near the target is. But  the farthest it is from the equator,  the more you have to worry about it displacing in two different axes in relation to your aproaching ship: further/closer, and to the sides,  forcing you to compensate for more variables.
    4. Building outpost on the exact poles will eliminate all issues mentioned here. However those sites are impractical for other reasons,  above all,  the huge delta-v requirements to go into polar orbits in the first place. Also,  usually the higher the ground,  the easier to land on it, however the advantage quickly disapears as the site moves away from the equator. Yup,  equatorial bases are usually the best choice.
    I'll do some pictures,  re-visit this post later on and they will be there.
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