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Satellite capabilities, geophysical observations, southern hemisphere anomalies, geomagnetically trapped particles, ionospheric current, and mesospheric structure - conference
Lower ionospheric electron concentration and collision frequency measurements by Nike-Apache rockets, suggesting geomagnetic anomaly in D region
Maximum entropy power spectra of the ionospheric electron density were constructed to enable PINY to compare them with the power independently obtained by PINY with in situ measurements of ionospheric electron density and neutral species performed with instrumentation carried by the Atmospheric Explorer (AE) satellite. This comparison corroborated evidence on the geophysical reality of the alleged electron density irregularities detected by the ASTP dual frequency Doppler link. Roughly half of the localized wave structures which are confined to dimensions of 1800 km or less (as seen by an orbiting Doppler baseline) were found to be associated with the larger crest of the geomagnetic anomaly in the Southern (winter) Hemisphere in the morning. The observed nighttime structures are also associated with local peaks in the electron density.
The effects of large impacts on the environment are discussed and include thermal effects, atmospheric effects, changes in ocean temperatures, and geomagnetic anomalies. Biological factors such as extinction and increases in mutation development were investigated. Geological anomalies studied include stratigraphic gaps, extinction of entire boundary layers from the geological record, and geochemical oddities. Evidence was examined for impact cratering throughout the world.
Observations of penetrating electron precipitation at two L of about 4 stations in the southern hemisphere, Kerguelen and Siple Station, Antarctica, are summarized. The nearly complete absence of precipitation at Kerguelen and its frequent occurrence at Siple Station is explained in terms of their location with respect to the center of the South Atlantic geomagnetic anomaly at L of about 4. Conclusions which result from this explanation are discussed along with questions which remain concerning penetrating electron precipitation.
It is argued that Baker et al. (1987) may have underestimated the electron precipitation rate in the southern hemisphere in the region extending west to about 90 deg in longitude from the southern extension of the center of the South Atlantic geomagnetic anomaly (SAGA). In a reply, it is noted that Baker et al. restricted their study to the case of uniform precipitation in latitude and longitude throughout the outer-zone area, thus entailing a great simplification of the real-world situation. Comments are made on the effects of the SAGA on electron precipitation.
Longitudinal asymmetry of trapped energetic electron intensities attributed to lowering of mirror points in South African anomaly
Aeromagnetic survey of Meteor Crater, Arizona, with magnetometer and interpretation of observed magnetic anomaly
Loss and replenishment of trapped electrons at middle latitudes and high B values, noting electron transmission through South Atlantic anomaly
Gemini IV proton-electron spectrometer measurements of radiation environment in geomagnetic field anomaly intersected by spacecraft orbits
Temporal stability of inner zone protons determined by Injun I satellite measurements in vicinity of South Atlantic magnetic anomaly
Vertical incidence ionospheric absorption measurements from ground station criteria for recognizing winter anomaly
The winter anomaly in the winter of 1982/83 is compared with the winter anomalies of earlier winters (1960-82) from the point of view of amplitude and timing of the winter anomaly, and geomagnetic and dynamic activity influences. Some evidence of a negative influence of sudden stratospheric warnings on the winter anomaly is given.
Lack of influence of capetown gravity anomaly on van allen radiation belt
Observations of Van Allen radiation regions by Explorer VI satellite - Capetown anomaly and shape of outer belt, particle trajectories, and neutron albedo decays
Pulsating auroras as source of infrasonic waves associated with geomagnetic activity
Asymptotic acceptance cone variation of cosmic ray neutron monitors in geomagnetic field distorted by solar wind, noting particle trajectories
NASA research on collective effects in collisionless plasmas, particularly geomagnetic cavity problem in astrophysics