Geomagnetic activities have a crucial impact on Earth, which can affect spacecraft and electrical power grids. Geospace scientists use geomagnetic index, called the Kp to describe overall level of activity. This index is an important indicator disturbances in Earth’s magnetic field used by U.S. Space Weather Prediction Center as alert warning service for users who may be affected disturbances. ...

The geomagnetic field of the earth shields from hazards solar wind which is constantly buffeting making assume a comet-like shape. In this paper, interplanetary and data were simultaneously analyzed for period cycle 24. analyses allowed us to determine any teleconnections between activity within period. Results show that are highly connected at high latitudes but same cannot be said mid low lat...

Abstract The occurrence characteristics of 150-km echoes in low-latitude regions are studied using the Equatorial Atmosphere Radar (EAR) Indonesia. long-term observation by EAR enables us to study statistically. It is shown that rate observed shows a semiannual variation with two peaks solstices and negative correlation both EUV flux $$\Sigma$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/M...

The influence of the geomagnetic field on the development of air showers is studied. The well known International Geomagnetic Reference Field was included in the AIRES air shower simulation program as an auxiliary tool to allow calculating very accurate estimations of the geomagnetic field given the geographic coordinates, altitude above sea level and date of a given event. Some test simulation...

The rate of secular variation occasionally undergoes a sudden, sharp change, called a geomagnetic jerk. Such jerks have been detected in geomagnetic time series, centered—over the last four decades—around 1971, 1980, 1991, and 1999; others have been inferred from historical records. The geomagnetic jerks represent a reorganization of the secular variation, implying an internal origin, as establ...

Axonal ensheathment and myelination, one form of axon-sheath cell interaction, was studied under normal earth magnetism, in the absence of terrestrial magnetic field, and under a 5 G (0.0005 T) magnetic field. Results indicate that the geomagnetic field is necessary for the fundamental biological activity of axonal ensheathment and myelination. The exact mechanism of action remains obscure.

A previous application of extreme-value statistics to the ®rst, second and third largest geomagnetic storms per solar cycle for nine solar cycles is extended to fourteen solar cycles (1844±1993). The intensity of a geomagnetic storm is measured by the magnitude of the daily aa index, rather than the half-daily aa index used previously. Values of the conventional aa index (1868± 1993), supplemen...

The Japanese Antarctic Research Expedition has conducted geomagnetic observations at Syowa Station, Antarctica, since 1966. Geomagnetic variation data measured with a fluxgate magnetometer are not absolute but are relative to a baseline and show drift. To enhance the importance of the geomagnetic data at Syowa station, therefore, it is necessary to correct the continuous variation data by using...