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King, J. H.

Publications and source records attributed to King, J. H..

45 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

A survey of the interplanetary magnetic field

All interplanetary magnetic field measurements from near-earth satellites have been collected in the form of hourly averages for the years 1963-1974. Solar cycle variations of the field and the exceptional events of this cycle are discussed in relation to the associated cosmic ray events, and statistical properties of the field over this period are presented. The presence of magnetic blobs as a permanent feature of the field is demonstrated and explained. The implications of these results for the theory of cosmic ray modulation are presented and analyzed.

Barouch, E.↗
NASA NTRS1974

Energetic solar proton versus terrestrially trapped proton fluxes for the active years 1977 - 1983

Ratios of solar to trapped proton fluences were computed for circular-orbit, geocentric space missions to be flown during the active phase of the next solar cycle (1977-1983). The ratios are presented as functions of orbit altitude and inclination, mission duration, proton energy threshold, and the chance the mission planner is willing to take that the actually encountered solar proton fluence will exceed the design fluence provided by the statistical solar proton model. It is shown that the ratio is most sensitively dependent on orbit altitude and inclination, with trapped protons dominant for low inclination, low and mid altitude orbits and for high inclination, mid altitude orbits. Conversely, solar protons are dominant for high inclination, low altitude orbits, and for low and high inclination, high altitude orbits.

King, J. H.↗
NASA NTRS1974

Empirical solar proton model for orbiting spacecraft applications

An empirical model for energetic solar proton fluxes is presented. With this model the effects of such protons on geocentric space missions, to be flown during the next solar active period (1977-1983), and with orbits involving partial magnetospheric shielding, may be estimated. A synoptic background review is given, followed by a detailed discussion of the model's use, errors, uncertainties, and limitations, including sample calculations which demonstrate the application of specific or general project missions. Finally, for circular trajectories, percentage exposure maps are presented, depicting fractional mission times spent outside particular L shells as functions of orbit altitude and inclination.

Stassinopoulos, E. G.↗
NASA NTRS1974

Solar proton fluences for 1977-1983 space missions

The probability with which any given solar proton fluence level will be exceeded during a space mission is computed for mission to be flown during the active phase of the next solar cycle (1977-1983). This probability is a function of fluence level, proton energy threshold, and mission duration. Calculations are based on 1966-1972 data only. In estimating mission fluences, a distinction is made between ordinary and anomalously large events. Probable numbers of each type of event are estimated from Burrell's extension of Poisson statistics. Fluences of all anomalously large events are assumed to have a spectrum given by the August 1972 event, while fluences of the ordinary events are assumed to obey a log normal distribution.

King, J. H.↗
NASA NTRS1973

Solar proton fluences as observed during 1966-1972 and as predicted for 1977-1983 space missions

The probability with which any given proton fluence level will be exceeded during a space mission is computed for missions to be flown during the active phase of the next solar cycle (1977-1983). This probability is a function of fluence level, proton energy threshold, and mission duration. Data on the major solar proton events of 1966-1972 are given; it is argued that only this data set (and not that of the previous solar cycle) is appropriate for estimating next-cycle fluences. Probable numbers of each of the two types of events are estimated from Burrell's extension of Poisson statistics. Fluences of all future anomalously large events are assumed to have a common spectrum, that given by the August 1972 event. Fluences of the ordinary events are assumed to obey a log normal distribution. It is shown that for much of the confidence-level mission-duration regime of interest, at least one anomalously large event will occur; and given such an occurrence, the ordinary-event contribution to mission fluence is negligible.

King, J. H.↗
NASA NTRS1972

An empirical model of energetic solar proton fluxes with applications to earth orbiting spacecraft

An empirical model for energetic solar proton fluxes is presented. With this model, the effects of such protons on geocentric space missions, to be flown during the next solar active period (1966-1983) and with orbits involving partial magnetospheric shielding, may be estimated. A synoptic background review is given, followed by a detailed discussion of the model's analytic development. Also given are comments on the model's use, errors, uncertainties, and limitations, including sample calculations which demonstrate the application of specific or general project missions. Finally, for circular trajectories, percentage exposure maps are presented, depicting fractional mission times spent outside particular L-shells as functions of orbit altitude and inclination.

Stassinopoulos, E. G.↗
NASA NTRS1971

IMP series report/bibliography

The main characteristics of the IMP spacecraft and experiments are considered and the scientific knowledge gained is presented in the form of abstracts of scientific papers using IMP data. Spacecraft characteristics, including temporal and spatial coverages, are presented followed by an annotated bibliography. Experiments conducted on all IMP's (including prelaunch IMP's H and J) are described. Figures are presented showing the time histories, through the end of 1970, of magnetic field, plasma, and energetic particle experiments.

King, J. H.↗