I think you're forgetting that astronomers care about wavelengths of light other than visible light — that is a very, very narrow range of the spectrum of radia

I think you're forgetting that astronomers care about wavelengths of light other than visible light — that is a very, very narrow range of the spectrum of radiation. In the infrared, for example, every satellite looks like a blazing star. In the radio spectrum, every satellite that transmits signals in this band looks hundreds of thousands of times brighter than a star.