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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The effect on the lunar orbit of meteoritic accretion.
Variation in Earth-Moon distance as result of meteoritic impact
Dynamical capture of the moon by the earth
Numerical integration of equations for dynamic capture of moon by earth
Signs of crossing by the moon of the earth's magnetosphere tail according to data of charged particle traps on the first artificial satellite of the moon /Luna-10/
Space probe charged particle data evidence for moon crossing of Earth magnetospheric tail
A harmonic L4 orbit for the very restricted four-body problem
Harmonic L-4 orbit for very restricted four-body problem determined by method of general perturbations using Chebyshev series
Physical constants as determined from radio tracking of the Ranger lunar probes
Radio-tracking data from Ranger lunar missions for estimated physical constants of earth and moon
Stable periodic orbits about the Sun perturbed Earth-Moon triangular points
Numerical verification of stable, periodic, coplanar orbit existence about Sun perturbed Earth-Moon triangular point
The scientific value of manned lunar exploration.
Scientific value of manned lunar exploration
The origin and dynamical evolution of the moon.
Tidal friction theory of lunar origin and dynamic evolution
Regenerative Environmental Control Systems for Manned-Lunar Spacecraft
The historic earth orbital flight of the Mercury space capsule on February 20, 1962 has illustrated that man has the capability of creating instrumentation and equipment which permit him to survive outside the protective earth atmosphere which, in time, has served both as a shield and a barrier. Because of this great achievement man need no longer restrict himself to earth-space but may direct his resources to expand his zone of operation to earth-moon space. However, in order to exploit this new frontier many problems must be solved which are not mere extensions or extrapolations of those already treated. The problem associated with providing man with an adequate environment for extended periods in the earth's atmosphere, earth-moon space and on the lunar surface is indeed extensive. Trapped radiation, solar flare activity, meteoroid bombardment, solar radiation and the hard vacuum of space are no longer merely phenomena. of scientific interest; they describe the operating environment of manned earth-lunar spacecraft. In order that man may effectively operate in the earth-moon space, myriads of systems and subsystems of varying types and functions must be devised and integrated into an efficient, reliable man-machine complex. This paper will consider only one small aspect of this problem--that is, the problem of providing man with an adequate gaseous and thermal environment in earth-lunar spacecraft. Control of atmospheric gases in manned sealed environments will be treated in Part I. Part II treats thermal regulation and atmosphere control requirements of mobile life support systems for lunar exploration.
Station-keeping in the vicinity of collinear libration points with an application to a lunar communications problem.
Feedback control system to position satellite in vicinity of unstable collinear libration point applied to lunar communication problem
Systems analysis
Selenodesy experiment, data compression, Mars and Venus mass data, Earth-Moon mass ratio, orbits for three-body problem, and unbraked impact time for lunar landing mission - systems analyses
Station-keeping in the vicinity of collinear libration points with an application to a lunar communications problem.
Feedback control system to position satellite in vicinity of unstable collinear libration point with application to lunar communication problem
Secular changes in meteoritic flux through the history of the solar system.
Secular variations of meteoritic and asteroidal fluxes in Earth-Moon region, using lunar craters as records of meteoritic impacts
Lunar Flight Study Series: Volume 4. Preliminary Investigation of the Astronautics of Earth - Moon Transits
Preliminary information on flight profiles, velocity budgets and launch windows for Apollo and Support Vehicle flights is presented in this report. A newly conceived method of establishing a flight mechanical classification of the earth-moon transits is discussed. The results are empirical and are designed to contribute to the mission mode selection.
Lunar transportation - Far-term options.
Reuseable shuttle transportation system for lunar base logistics, estimating cost and performance
Postflight Evaluation of Atlas-Centaur AC-5 (Launched 2 March 1965)
The Atlas-Centaur AC-5 vehicle was launched from ETR Complex 36A on March 2., 1965 at 8:25.04 a.m. EST. Within about 1 second after launch the thrust of the Atlas booster engine decayed rapidly; the vehicle settled back on the launch pad and was quickly destroyed by fire and explosion. Considerable damage was sustained by the launch complex and its associated equipment. Loss of booster engine thrust was due to fuel depletion at the turbopump inlets, which is attributed to closure of the fuel prevalve or the staging valve. To preclude the recurrence of either of these fuel valving malfunctions, the following corrective action has been taken: The remote control actuator has been replaced by manual operation of the Atlas fuel prevalve; the internal passage dimensions in the staging valve have been increased to lessen the hydraulic load on the valve poppet. In addition to the Atlas fuel system malfunction, a failure in the power control circuitry of the Centaur guidance computer resulted in partial removal of power at umbilical ejection. To prevent such a guidance system failure on future flights some redundant circuitry has been eliminated and more rigorous checkout procedures have been adopted. No further anomalies were discovered in the telemetered data prior to the Atlas booster thrust decay. A prime objective of the AC-5 flight was to place a dynamic model of the Surveyor spacecraft in a simulated lunar transfer trajectory. An important facet of this problem is the demonstration of a launch-on-time capability in accordance with the proper Earth-moon relation. The window opening time was established at 8:25 a.m. EST; thus the actual launch occurred within 4 seconds of the planned time.
Lunar Flight Study Series: Volume 5. Trajectories in the Earth-Moon Space with Symmetrical Free Return Properties
An extensive investigation has been made of the characteristics of so-called "free return" trajectories. For the purposes of the study., these trajectories are defined as having certain symmetric properties which afford flight to the vicinity of the moon and return to earth without need for propulsion after the initial boost phase. The restricted three-body model for the earth-moon-probe system is used throughout. Two kinds of free return trajectories are shown to -exist and are studied. Of particular interest is the fact that for one kind of free return path, the largest inclination which can be achieved between the flight plane at periselenum and the plane of the moon's orbit about earth is about 10. 8 degrees while for the other kind of path the largest possible inclination is dependent on ·the radius at periselenum. In this case the inclination is limited to about 14 degrees or less for periselenum radius of 1938 km, but may be as great as 90 degrees with periselenum radius of 21150 km. Trajectories are also demonstrated which pass in front of the moon. These exhibit inclination behavior very much like that given by trajectories which go behind the moon. The injection velocity for these trajectories also changes only slightly from the circumlunar trajectories (less than 2 m/s for periselenum radius of 1938 km). However, the position of injection is changed considerably and the flight time may be increased by as much as five times that for circumlunar flight.