geomagnetic observatories are constructed to continuously record the earth’s geomagnetic field. the importance of such buildings has resulted in an increasing construction of geomagnetic observatories all over the world. although geomagnetic observatories are sometimes unknown to most people and even some scientists, these very important data centers have been measuring the geomagnetic field fo...

Multi-MeV electron drift-periodic flux oscillations observed in Earth's radiation belts indicate radial transport and energization/de-energization of these belt core populations. Using multi-year Van Allen Probes observations, a statistical analysis is conducted to understand the characteristics this phenomenon. The results show that most result from resonant interactions with broadband ultralo...

[1] The daily variation of the geomagnetic field during quiet time at equinox features a longitudinal dependence, which is observed in the dip-latitude/longitude frame. Two explanations are considered: (1) the longitudinal changes of the geomagnetic latitude at constant dip-latitude and (2) the longitudinal variations of the main field, which modulates the ionospheric dynamo e.m.f. and determin...

JULIA radar observations of equatorial spread F (ESF) plasma irregularities made between August, 1996 and April, 2000 are analyzed statistically. Interpretation of the data is simplified by adopting a taxonomy of echo types which distinguishes between bottom-type, bottomside, topside, and post-midnight irregularities. The data reveal patterns in the occurrence of ESF in the Peruvian sector that...

[1] The ionospheric heating facility of the High Frequency Active Auroral Research Program (HAARP) has been used extensively in the last 3 years for injection of ELF/VLF waves into the magnetosphere via modulated heating of the overhead auroral electrojet currents. Of particular interest are waves that are observed to be nonlinearly amplified after interaction with hot plasma electrons in the E...