Engineering topics
Publications and source records attributed to Gordon, H. J..
The Ulysses mission ESA spacecraft with ESA and NASA experiments explores the polar regions of the sun by sending a spacecraft on a trajectory out of the ecliptic after a Jupiter flyby. After correcting for launch errors and refining the aimpoint, orbit determination results show the change and general improvement in the Jupiter arrival point. Orbit determination results are further discussed, and future plans are mentioned.
Ulysses, a cooperative NASA and ESA project, measures charged and neutral particles, magnetic fields, and electromagnetic wave emissions from the Sun's polar regions and the out of elliptic heliospheric environment. ESA supplied the spacecraft and one half of the instruments, and is in control of the spacecraft and its attitude. NASA supplied the power supply, one half of the instruments, the launch vehicle, and tracks the spacecraft and performs the navigation. Orbit determination results mapped to the time of Jupiter's arrival show improved accuracy and consistency over the course of the mission to date. Solar radiation pressure model uncertainties are major contributors to orbit determination errors, but are being estimated more accurately as data are accumulated.
Performance of Mariner Mars 1969 mission by flight and Earth-based elements during launch and space flight phases - Vol. 2
Determination of orbit estimates for Mariner 6 and 7 space probe flights
Mariner 7 preencounter anomaly in radio tracking data and trajectory investigated by computerized simulation
Midcourse Maneuver Operations Program /MMOP/ computes the required velocity change to correct a spacecraft trajectory. The program establishes the existence of maneuvers which satisfy spacecraft constraints, explores alternate trajectories in the event that some out-of-tolerance condition forces a change in plans, and codes the maneuvers into commands.
Trajectory design and mission planning for Mariner Venus 67 /Mariner 5/ space project, discussing perturbative forces, orbit determination and midcourse guidance
Functional design of Mariner midcourse maneuver operations program
Earth-based midcourse guidance for Mariner Mars 1964 space probe, using small rocket engine to obtain desired trajectory correction
Onboard optical guidance system for planet-bound spacecraft including covariance matrices for orbital parameters, system and instrument biases and parametric course accuracy curves
Probability of depositing viable organisms on Mars during 1964 Mariner mission