Is there a big orbit registry somewhere? Yes. https://www.unoosa.org/oosa/osoindex/search-ng.jspx https://www.unoosa.org/oosa/osoindex/search-ng.jspx Each indiv

Is there a big orbit registry somewhere? Yes. https://www.unoosa.org/oosa/osoindex/search-ng.jspx https://www.unoosa.org/oosa/osoindex/search-ng.jspx Each individual object is observed every few weeks, and then they estimate its current position with math and physics. How do they track them? With big expensive radar systems, mostly paid for by the military. It's an international collaboration. https://en.wikipedia.org/wiki/Space_domain_awareness#Systems https://en.wikipedia.org/wiki/Space_domain_awareness#Systems