This is an incredibly naive approach. All asteroids emit light in the infrared, to detect and track asteroids just takes an infrared telescope making apparent motion against any background completely irrelevant. NASA is working on this: https://en.m.wikipedia.org/wiki/NEO_Surveyor
inkl has pretty good variety of news sources for a reasonable subscription fee, i subbed for years then started using apple news. Unfortunately i cannot recommend inkl because you have to email support to cancel your subscription, they offer a 50% discount if you try to cancel but that business practice of sign up with one click, email support to cancel i cannot condone.