Today Hydrogen Maser time standards are utilized in interferometric astronomical observations of extra-galactic radio sources (Quasars) to determine station positions, motion of the Earth's axis of rotation, and fluctuations in the length of day.
(Hydrogen Maser time standards; are utilized; L:in interferometric astronomical observations of extra-galactic radio sources; to determine station positions; T:Today)
Hydrogen Maser time standards
are utilized
L:in interferometric astronomical observations of extra-galactic radio sources to determine station positions T:Today