I saw a series of half hour documentaries on various satellites that had been sent out to explore various aspects of our solar system and found myself wondering how we aim our telemetry signals to hit (typically) tiny satellites that are (typically) millions of kilometers away and actually reach them.
The signal sent from the satellite back to Earth naturally has a similar issue. The Earth is obviously much bigger than the satellite but given the immensity of the universe, it still strikes me as exceedingly difficult to hit from great distances away.
Only the very best snipers in history can hit a target more than a mile or two away so how do we send a radio signal so accurately that it hits a satellite so very far away?
I know that space is a vacuum so there are no currents to blow a spacecraft off course but the gravity of the various bodies passed by the spacecraft can change its course, even if the body is relatively distant. Although we've mapped many planets and moons, we're still discovering moons regularly. I don't expect we've mapped nearly every asteroid or comet yet but every one of those bodies could affect a passing spacecraft so the calculation of where a spacecraft will be at a given time must be extremely challenging, perhaps enough to make it difficult to find.
Although I've heard of satellites couldn't transmit or receive any more, I can't recall ever hearing of one that had been "lost" in the sense of not being able to find it to get a signal to it. Have we ever lost satellites in that sense?
FWIW, I read the Wikipedia article on telemetry but it was very general and didn't explain how we locate satellites precisely enough to send them signals. I am NOT a mathematician or engineer so I doubt I would follow explanations in engineering textbooks. I'm just a space enthusiast who is looking for a layman's understanding of how telemetry finds spacecraft.