See the question and my original answer on StackOverflow

This "Celestron.Telescope" string is called a ProgID (you can google on this term quite easily).

They arere located under the HKEY_LOCAL_MACHINE\SOFTWARE\Classes registry key for the whole machine and in HKEY_CLASSES_ROOT for the current running user.

When COM creates an instance of a component, it will use the current user's view of the registry. Most keys are in HKLM but there can be some local overrides in HKCR.