Tristan Cools writes: > it has never been understood what those satellites were but it is believed > that the USA 40 satellite was a prototype of a KH12 imaging satellite and > USA 41 was probably a small Elint satellite. > > Because of the secretness of both payloads it is almost impossible to know > wether the fragmentation came from USA 40, 41 or the rocket body from USA 40. This is not true on several counts. Most analysts now believe that USA 40 was a second generation SDS communications data relay satellite (see my article in Quest magazine, for example). The US filings to the United Nations actually have included orbits (not full elements) from the debris storm which allow us to infer that the debris storm is from the USA 40 rocket body, which may be a Leasat-type PKM.