Open AccessBrightening of 630.0 nm equatorial spread‐F airglow depletions
Author(s) -
Martinis Carlos,
Baumgardner Jeffrey,
Mendillo Michael,
Su ShinYi,
Aponte Nestor
Publication year - 2009
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2008ja013931
Subject(s) - airglow , solstice , zonal and meridional , geology , latitude , atmospheric sciences , brightness , geophysics , radar , sky , physics , geodesy , astronomy , telecommunications , computer science
Observations from the Boston University all‐sky imaging system at Arecibo, Puerto Rico (18.3°N, 66.7°W, 28°N mag), show an unusual behavior of nighttime 630.0‐nm airglow depletions. Associated with equatorial spread‐F (ESF), these structures move eastward before reversing their motion and become airglow enhancements. Few other cases have been found, all during December solstices. For the case study presented here, data from the Arecibo incoherent scatter radar and the Republic of China Scientific Satellite (ROCSAT‐1) provide supporting information. The radar shows that around local midnight the background zonal and meridional plasma motions reverse to westward and southward, respectively. ROCSAT‐1 shows enhanced ion density, i.e., a low‐latitude plasma blob, above the bright feature recorded by the all‐sky imager, indicating a possible connection between both phenomena. Drifts parallel to the magnetic field are observed only in the region where the enhancement occurs. One possible interpretation of this change in the brightness of the depleted structure involves the influence of northward meridional winds and a reversal in the zonal drift motion, most likely caused by a zonal wind reversal.