High Precision Time Transfer in Space with a Hydrogen Maser on MIR

An atomic hydrogen maser clock system designed for long term operation in space will be installed on the Russian space station, Mir, in late 1997. The H-maser's frequency stability will be measured using pulsed laser time transfer techniques. Daily time comparisons made with a precision of better than 100 picoseconds will allow an assessment of the long-term stability of the space maser at a level on the order of 1 part in 10(15) or better. Laser pulse arrival times at the spacecraft will be recorded with a resolution of 10 picoseconds relative to the space clock's time scale. Cube corner reflectors will reflect the pulses back to the earth laser station to determine the propogation delay and enable comparison with the earth-based time scale. Data for relativistic and gravitational frequency corrections will be obtained from a GPS receiver. Presented at the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (27th) held in San Diego, CA on 29 Nov - 1 Dec 1995. Published in the Annual Precise Time and Time Interval Applications and Planning Meeting Proceedings, p181-192, Dec 1996.