What is this black thing, roughly the size of a coffee mug, cylindrical in shape, attached to a circular bracket, on the side of my neighbours house? Its position can be adjusted, doesn’t light up or make noise. Not sure on weight as it is fixed to the wall. We think that it’s plastic.
Infrared camera?
As I said in another comment, I’d ruled out a camera cause there’s no lens bit…but can you get cameras like this?
Technically yes, but there's no way your neighbors would probably have something like a lidar array:
Check out this page though, it has some really interesting visuals on what it does :)
https://www.jouav.com/products/jolidar-lr.html