Here's a Tip for when you are Dscanning planets in close range .(0.5 - 0.1 au)
Planets are big, and their warp in location is not at the center of planet, so when you are scanning planets in close range what actually happens is You are Scanning the Center of the planet and not the Warp in LocationTo fix that issue, slightly increase your Scanning angle from 5% to 15% so the increase in angle probably targets the warp in location too OR Scan the Customs Office instead because most of the time thats where the warp in location is.
And on another note Make sure your scanning range is set at 1AU or closer when you are scanning the close objects, Many times i warped to a moon to kill someone just to realize He wasnt at the moon but at some other Celestial which was Few AUs away.
This tip comes in handy when you are looking for Certain Types of NPCs such as Insurgency fleets or Hunting in Pochven.