Question: The IERS Reference Meridian (IRM), is the prime meridian (0° longitude) maintained by which organization, it is also the reference meridian of the Global Positioning System (GPS), originally Navstar GPS, is a space-based radionavigation system owned by the United States government and operated by the United States Air Force?
Sentence (from "Global Positioning System"): The Global Positioning System (GPS), originally Navstar GPS, is a space-based radionavigation system owned by the United States government and operated by the United States Air Force.
Relevant evidence: Yes