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Satin, A. L.

Publications and source records attributed to Satin, A. L..

Missions to Titan /1983-2000/ - An analysis of orbiters and entry vehicles

Mission Analysis data is presented which forms a basis for planning future missions to Titan, the seventh moon of Saturn. Four Titan mission options are studied: orbiters, probes, penetrators and landers. The generated data supports these mission modes. A comprehensive launch and trajectory analysis of earth to Saturn opportunities from 1983 to 2000 is given. Direct ballistic and Delta VEGA trajectory modes are evaluated. Orbital insertion, orbital trim, entry vehicle deployment options are all studied in parametric detail.

Hendricks, T. C.↗

Navigation and performance analysis of a Mars surface sample return /MSSR/ mission

A Viking-derived MSSR mission involves a rendezvous in Mars orbit between the sample-carrying Mars Ascent Vehicle (MAV) and a modified Viking Orbiter spacecraft. Conditions for the automatic terminal rendezvous phase are established by an initial earth-controlled phase which uses very accurate relative state information obtained by multi-vehicle interferometric tracking data. A navigation analysis has demonstrated sufficient performance and control capability to satisfy those conditions prior to terminal rendezvous. Specific performance constraints for the mission are developed, leading to a sizing of vehicle weight requirements and trades applicable to a 1981 MSSR, launched by a single Titan IIIE/Centaur.

Satin, A. L.↗

Navigation requirements for rendezvous with the satellites of Mars.

Navigation aspects of a rendezvous mission to Deimos (the outer satellite of Mars) were examined using a modified Viking Monte Carlo error analysis program. Rendezvous is initiated by two-impulse transfer from an observation orbit cotangent with the orbit of Deimos. Television sightings of the satellite against a star background will allow a 20 km closest approach radius (R99) 99% of the time. This is well within the 100 km range of the terminal rendezvous radar. An additional delta-V capability of about 100 m/sec (above the nominal) must be allocated to account for the statistical nature of the mission. This delta-V requirement was found to be very sensitive to the level of satellite ephemeris error and maneuver execution error. The R99 on the other hand, is sensitive to the in-orbit DSN error and the maneuver execution error.

Satin, A. L.↗