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A spark chamber track finding program has been written. The accuracy of the location of the track is good, and if the chamber contains many spurious sparks the computation time is much less than the time used by a least squares fit routine. Multiple tracks can be found and interaction vertices can thereby be determined.

The magnetic coordinates of the Pioneer 10 spacecraft and the five innermost satellites are reported for the Jupiter encounter. The D sub 2 offset is used to make the calculations. Magnetic coordinates are needed for the interpretation of the trapped particle measurements, including the absorption effects of the satellites. Contours of constant field magnitude and magnetic latitude are given at the surface of Jupiter for the D sub 2 model. The system 3 longitude of a spacecraft at Jupiter is derived, and formulas given for the relationships between system 1, 2, and 3 longitudes. The longitude of the magnetic dipole increases by about 3 deg per year, due to the inaccurate rotation rate used to define system 3 longitude.

An approximate empirical potential energy hypersurface has been fitted to a combination of experimental results and molecular structural information, by means of a trajectory analysis, without the restrictions imposed in Part I. On the basis of this, predictions are made for the incident energy dependence of the reactive cross sections when the reactants are T+CH4, T+CD4, D+CH4, H+CD4, and H+CH4. The scattering properties and some aspects of the energy disposal in these reactions are also examined, and the most characteristic molecular dynamic features of the reactions are described.

Approximation formulas are found for\(\dot x(0)\) and\(\dot x(1)\), wherex(t) satisfies\(\ddot x = f(x,t)\),x(0)=x0,x(1)=x1. The results are applied to an example of two-body motion.

The Ad Dawadmi Batholith in central Saudi Arabia is cut by three strike-slip faults which form part of the Najd transcurrent fault system. Two of the three faults end in the area studied; the third, which now extends beyond the area, is shown to have formed in two stages. Two of the faults are associated with second order fractures. One of these fracture systems, together with a dyke swarm, occupying extension fractures and shown to be synkinematic, has been used to construct trajectories of principal compressive stress and maximum shearing stress as they existed during one episode of second order faulting. The sequence of formation of the three master faults, their second order fracture systems and the dyke intrusion has been established. It is shown that the faults, during their formation, propagated into the area from the south-east and one subsequently extended north-westward. Comparison shows that the second order fault pattern conforms closely with a theoretical model of fractures associated with the tip of a master fault under ‘uniaxial compressive stress’ conditions. The construction of stress trajectories permitted the forecasting of potential second order fault orientations and sense of displacement throughout the area. This is economically important because many of the second order faults and associated pinnate extension fractures contain mineral veins.

Dimensionless differential corrections and proper coordinate system for generalized preflight guidance analysis

Analysis of meteor luminous efficiency based on photographic data, taking into account fragmentation effects

Unmanned spacecraft trajectory and guidance considerations for close flyby of planet Mercury

Neighboring optimum feedback guidance to motivate min-distance lookup parameter determined by minimizing metric function of perturbed state and reference trajectory

Normalized hodographic mapping for constrained trajectory families, discussing mapping concepts, information content and applications

Differential games with open or closed loop strategies, giving theory of sequences of approximation games defined on finite dimensional spaces

Dynamic instability of rolling high drag planetary entry vehicles at subsonic speeds, noting angle of attack divergence in computerized entry simulation

Science subsystems for Jupiter flyby missions, discussing equipment selection, mission planning, spacecraft design and trajectory and constraints on vehicle configuration

Navigation data from Mariner Mars 1969 TV pictures, estimating spacecraft trajectory to planetary center

Exploration capabilities provided by Jupiter gravity assisted trajectories compared to direct ballistic flight trajectories

A control net of Mars has been computed from measurements of 115 control points identified on the Mariner 6 and 7 pictures. Most of these points are located with respect to topographic features on the surface of Mars, and their areographic coordinates were computed by photogrammetric techniques. These pictures offered the first opportunity to establish a control net of Mars based on topographic detail.

plication to modern engineering problems/' Douglas Aircraft Co., Santa Monica, Calif. (1957); unpublished lecture notes. 8 Miele, A., "General variational theory of the flight paths of rocket powered aircraft, missiles and satellite carriers," Astronaut. Acta 4, 264-288 (1958). 9 Bauer, A. B. and Thelander, J. A., "A variational method for finding the flight path which gives the maximum burnout velocity for a multistaged rocket vehicle," Douglas Aircraft Co., Long Beach, Calif., Engineering Rept. LB-25956 (June 1959). 10 Stewart, C. E. and Thelander, J. A., "Optimum trajectory analysis," Ford Motor Co., Aeronutronic Div., Tech. Rept. 11-1435(1961).

The reactor accident at Windscale on 10-11 October 1957 resulted in the release of radioactive fission products into the atmosphere over a period of several hours. Measurements were made of the fission products, particularly iodine-131, collected on filters exposed for the study of atmospheric pollution in many places in the United Kingdom and Europe: measurements were also made of the iodine-131 deposited on grass. These showed that the effluent had been widely dispersed, but that activities over England were about an order of magnitude greater than those found over the neighbouring areas of the continent. Meteorological trajectory analysis showed that the main portion of the cloud had remained over England until 15 October, and that the activities over continental Europe were due to the eastern edge of the cloud. Meteorological data were used together with the air concentration data to deduce that about 22,000 curies of iodine-131 were present in the cloud as it passed over south Lancashire and Yorkshire.

An air pollution episode during August 1970 over the central United States is examined. By use of surface visibilities and an 850-mb wind trajectory analysis, we observed the pollution to advance as much as 700 mi from the central midwest (source region) into the upper midwest and Great Plains (impact area). A large, nearly stationary high-pressure system over the source region allowed the pollution to accumulate beneath a mid-level subsidence inversion located generally near 700 mb. Southeasterly flow around the backside of the High and the northeasterly flow around a weak Low to the south advected the pollution into the impact area. At times, surface visibilities in parts of the impact area were restricted by haze to as little as 4 mi. Although particulate count data were meager, several stations recorded their highest particulate count of the year during the episode.

Algorithm for trajectory analysis in closed loop terminal guidance of solar electrically thrusted interplanetary spacecraft

Impulsive trajectories optimal and nonoptimal solutions, classifying known results for reference purposes

Launch vehicle injection error sensitivity minimization by trajectory shaping using excess booster capability

The alteration of the size distribution of lead aerosols was studied by the sensitive analytical technique of anodic stripping voltammetry and using Andersen Samplers (multistaged cascade impactors) to collect and sort the aerosol by size. It was found that lead aerosol size distributions do not vary greatly from one source area (essentially an area of heavy automobile traffic) to another, and that the lead aerosol size distribution does not respond noticeably to change of weather within a source area for 24 h sampling times. Short-term aging in clear air was studied by comparing the lead size distributions at three locations from downtown Chicago (a source area) with those found several kilometers downwind over Lake Michigan (a non-source area). Long-term aging in clear air was studied by comparing the size distributions of lead aerosols of various ages collected on Lake Michigan. Ages were assumed to be the travel time from shore to the sampling location, computed by a simple trajectory analysis. The aging studies did not show a clear-cut systematic alteration of the lead aerosol size distribution, although the large particle end of the distribution showed reduced relative concentrations for aerosols ages of 6 h or older. These results suggest very little modification of the shape of the lead aerosol size distribution by non-precipitative atmospheric mechanisms for equivalent particle radii larger than 0.2 μm.

Data from two flights of a new superconducting magnetic spectrometer are reported. This instrument was capable of a direct matter-antimatter separation in the cosmic rays. Antimatter events would appear in the spectrometer as trajectories which curve in the opposite direction to common matter, because of their negative charge. A brief description of the equipment and of the characteristics of the instrument is presented, along with the data processing techniques used. A new upper limit on the amount of antimatter in primary cosmic rays has been established. The limits are considerably lower than those for any previous experiment.

Mariner IV trajectory analysis and importance of flight-path selection in construction of basic mission profile

Mission analysis for 1972 Venus launch opportunity, discussing launch period selection and trajectory constraints for Atlas/Centaur vehicle

Translational forces on Mariner 5 stemming from attitude control system, determining trajectory for scientific and operational purposes

A review of engineering and research data requirements for altitudes 30-100 km is made, indicating a variety of concrete data applications above 30 km (10 mb). The required data have in large measure been provided from meteorological rocket soundings, of which 18,000 have been taken, at considerable cost, since 1959. Remote vertical soundings based on satellite infrared radiation measurements have been obtained since 1969 with considerable success to an altitude of 25 km (30 mb). From developmental work in progress, it is expected that reliable temperature soundings may be obtained to 40-45 km. A discussion of the overall reliability and utility of the satellite data leads to several conclusions regarding the continuing need for rocket soundings.

Lost City /Oklahoma/ meteorite photometric and trajectory data, comparing flight characteristics with other fireballs

Mars surface areodetic control net from Mariner 6 and 7 TV pictures, determining initial coordinate points and far and near encounter frames

Satellite-star optical navigation, a new spacecraft navigation technique has been successfully demonstrated during Mariner 9's approach to Mars in mid-November. As Mariner 9 approached Mars, 21 TV pictures of its satellites, Phobos and Deimos, were taken and transmitted to earth. On earth, these pictures were carefully processed in order to locate the positions of the bright satellites against the relatively faint star background. The objectives and performance of the preflight and real time activities leading to the successful demonstration of satellite-star navigation data are described.

Spacecraft guidance analysis of multiple outer planet mission utilizing gravity assist swingbys to achieve planetary flybys with single spacecraft

Mariner Mars 1969 flyby missions objectives, experiments, spacecraft configuration, trajectory design, sterilization, flight path control and photographic imaging

Three types of Mercury missions are considered: unmanned flybys, unmanned orbiters, and manned stopovers. Velocity requirements are assessed from consideration of four transfer modes: direct, unpowered Venus swingby, modified pericenter Venus swingby, and powered Venus swingby. The total and incremental impulsive velocity requirements, the mission durations, and Earth entry velocities, where applicable, are summarized. The lowest energy trip found for each of the missions employs a form of the Venus swingby mode. The unmanned flyby mission has a minimum impulsive velocity increment (AF) of 4.2 km/sec, and the unmanned orbiter mission a minimum total AF of 11.2 km/sec. For a 1000-kg payload at Mercury, these AF's correspond to 5000 and 47,000 kg, respectively, in Earth orbit, assuming a high-pressure chemical engine. Using a low-thrust nuclear engine would reduce the weight in Earth orbit by about 10% for the orbiter mission. The manned Mercury stopovers have a minimum AFr requirement of 18.2 km/sec with a corresponding stay time of 174 days and mission duration of 414 days. These missions require an Earth orbital weight of 0.9 to 1.8 X 10 kg, depending upon the trajectory mode/nuclear engine system selected.

A classical trajectory analysis has been made for the reaction F+H2→HF+H using a semiempirical potential energy surface. The reaction cross sections, energy distributions among reaction products, and angular distributions of products were determined as functions of initial relative velocity for low‐lying rotation–vibration states of H2 from Monte Carlo averages over a large number of trajectories. The modified London–Eyring–Polanyi–Sato surface used is characterized by a 1.68 kcal barrier in the entry valley with a net drop of 31.3 kcal to the exit valley occurring with F approaching H2. The reaction cross sections for H2 with υ = 0, J = 1 increased with relative velocity from a threshold value at a translational energy of 2.1 kcal to ∼ 6 A2 at 14 kcal. Rotational energy had little effect on the cross sections. For υ = 1, J = 1 the translational energy threshold was slightly lower and the upper limit to cross sections was ∼ 8 A2. The HF product was found to be strongly excited vibrationally with an averag...

Linearized manual space navigation incorporating redundant measurements to compensate for instrumentation inaccuracies

Round trip Mars missions combining a standard trajectory leg and a looping trajectory leg are suggested as an alternative to the more conventional trajectories. Looping trajectories are shown to make it possible to trade a slight increase in total mission time for a significant reduction in Mars stay time, with the possible added benefit of a decrease in energy requirements.

The molecular dynamics of the hydrogeniodine exchange reaction, H 2 + I 2 ⇄ 2 HI, have been examined in a classical trajectory analysis with trajectories selected within the transition region. The results yield the overall mechanism, the rate and the energy distributions of reactants and products for reaction at 700°K.

A classical trajectory analysis for the reaction H+I2→ HI+I at 600°K, using trajectories sampled within the transition region, shows vibrational excitation of the HI product molecules, mainly to the v=3 to v=5 levels. The calculated thermal rate is in approximate agreement with measurements by Sullivan. The product angular distribution is peaked at 110–120° relative to the incident atoms as measured for the reaction of D atoms by McDonald, LeBreton, and Herschbach. The translational energy distribution of the products is also similar to that found by McDonald et al. for the deuterium analog.

Graphical method for determining sounding rocket attitudes from optical sensor and flux gate magnetometer data

This paper describes an operational interactive computer graphics system, called Graphic ROCKET, currently being used as a performance analysis aid for preliminary design and evaluation of space vehicle systems. It provides means for rapidly specifying and evaluating the performance of a wide range aerospace vehicle designs and flight plans.

The report was written to provide a sample problem to be used to guide the user of the water droplet impingement prediction computer program. The report is intended to illustrate the preparation of input data and the interpretation of results.

Optimum launch trajectories for ATS-E mission with noncircular parking orbits, considering apogee motor size, perigee radius and duration constraints

Wind tunnel free-flight testing of reentry vehicle dynamics, noting capability for simultaneous two- dimensional viewing of model trajectories

Trajectory optimization, performance and other factors in analysis of low thrust solar electric propulsion Jupiter flyby mission

Manned space flight safety through mission trajectory design, considering hardware, software and operational constraints