To hit the back side, go to an extreme, where is says miss (I think) and then back off a little. Fire it then hit the key assigned to see the other side (Y by default? if on PC) to see where it hits and adjust as necessary for the next one. Don't forget to flip the view back or things can get confusing haha.

If you fire with the tick mark centered the probe will hit on the horizon, or edge. Some bodies are moving fast and you need a little Kentucky windage sometimes. Gravity may play a part too?

If you stop you can get off all probes within a few seconds once you get the hang of it. Probe radius makes a big difference. Felicity can do G3 which helps a bunch. But it can be done without it no problem, only the efficiency bonus becomes harder to get.