12-hour case study of auroral phenomena in the midnight sector: Electrojet and precipitating particle characteristics

Journal Article · Thu Sep 01 04:00:00 EDT 1977 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA082i025p03557· OSTI ID:7214281

Weber, E J; Whalen, J A; Wagner, R A; Buchau, J

Airborne observations of auroral activity at midnight were conducted for a period of 9 hours by employing an ionospheric sounder and all-sky cameras. During the observation period, two substorms occurred. The first substorm was assciated with a compression of the magnetosphere (as measured by Dst) and with oscillations of the earth's bow shock. At this time, auroral activity was characterized by a series of poleward and equatorward motions and by the absence of a breakup phase. Magnetic disturbances were confined to a small region in the midnight sector. The second auroral substorm displayed many of the features assocated with a large-scale polar magnetic substorm. For selected times the locations of the eastward and westward electrojets were inferred from a number of high-latitude magnetic records. All-sky photographs and ionosonde data indicate that the poleward edge of the westward electrojet was bounded by a westward moving auroral surge accompanied by a strong sporadic E ionization. The equatorward electrojet boundary was less well defined by visual auroral forms. Soft particle spectrometer measurements from the Isis 2 satellite were made in conjunction with the aircraft measurements and indicate that large fluxes of field-aligned electrons gave rise to the bright auroral surge, more isotropic fluxes of less energetic electrons contributing to the auroral E layer.

• Research Organization: Airforce Geophysics Laboratories, Hanscom Air Force Base, Massachusetts 01731
• OSTI ID: 7214281
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 82:25; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAE
AURORAL ZONES
CHARGED-PARTICLE PRECIPITATION
CURRENTS
E REGION
EARTH ATMOSPHERE
ELECTRIC CURRENTS
ELECTROJETS
ELECTRON PRECIPITATION
IONOSPHERE
IONOSPHERIC STORMS
MAGNETIC BAYS
MAGNETIC STORMS
PLANETARY IONOSPHERES
POLAR-CAP AURORAE