OK, so you are an extraterrestrial race interested in surveying our planet and our race…how do you go about it?
If it is stuff on a more granular scale (land use and so on), hiding an alien satellite up with all of ours seems to be a pretty safe bet. Telescopes, radio antennas, and various advanced sensor capabilities that we can only dream of. Highly unlikely that we’ll ever know they are there. Norrow-focused uninterceptable transmissions to whatever is your nearest starbase out in the great beyond. If it malfunctions it will either be just another hunk of space junk out of thousands, or will burn up when and if the orbit decays. [Self-destruct modules would also be a good idea]
If you want to see what is going on at the ground floor tho (as in interpersonal interactions between all of these semi-intelligent apes), things get a little bit trickier. My suggestion would be to hijack various insects with your high-tech devices, perhaps involving nano-level circuitry, use the organism’s base sensors and just add in your own tiny devices to transmit to the mother ships above. Bonus points if these circuits can quickly degrade after the organism’s death to thwart any nosy apes who might get ahold of one.
But flying around at high speeds in the atmosphere seems like the worst of both worlds. The resolution of your sensors doesn’t seem to be THAT much greater, 5 miles up vs. 100 miles, but now you are risking a crash if your craft malfunctions such that the overcurious apes can now acquire said wreckage and thus tech on a large scale (if not biology if you are dumb enough to actually have biological pilots flying the things).