Quantum RADAR!:

https://phys.org/news/2020-05-scientists-quantum-radar-prototype.html

So in a high noise situation with low powered radar, this new development means two superimposed microwave photons go out, one hits a subject but the detection does not depend on the sent photon to return, instead, the superimposed photon freaks out and they detect the change in superposition properties, allowing a very low power probe maybe useful in body scans and such. Amazing new technology!

Can it ever be used to improve very long distance radar such as to detect very distant asteroids?

@humy
I think that would depend on how long the two photons could be coerced into remaining superimposed.
For instance, to paint a distant target in the solar system, suppose it is a billion miles away or 1.6 billion Km, the speed of light means a one way trip of about one hour so two hours there and back. If such superpositional detection is to take place, that superposition has to remain intact for the full 2 hours.

I don't think there are experiments extant that produces that kind of stability.

Maybe one day but then that is only for ONE billion miles. It is FOUR bil to Pluto so the superposition there would have to last a full 8 hours.

It just gets worse the further you go out.

Have you seen the limits of superpositon in terms of time?