HR: 1330h
AN: SM23C-05    [Abstracts]
TI: The Brightest Stable Auroral Arc (SAR) Ever Measured
AU: * Mendillo, M
EM: mendillo@bu.edu
AF: Boston University, Center for Space Physics 725 Commonwealth Avenue, Boston, MA 02215 United States
AU: Wroten, J
EM: jwroten@bu.edu
AF: Boston University, Center for Space Physics 725 Commonwealth Avenue, Boston, MA 02215 United States
AU: Baumgardner, J
EM: jeffreyb@bu.edu
AF: Boston University, Center for Space Physics 725 Commonwealth Avenue, Boston, MA 02215 United States
AU: Kozyra, J
EM: jukozyra@engin.umich.edu
AF: University of Michigan, Space Physics Research Laboratory 2455 Hayward Street, Ann Arbor, MI 48109 United States
AB: A key role played by the "case study" approach in geoscience is to test mechanisms for their strongest possible effects. In the case of SAR arcs, this means the amount of heat conduction from the ring current/plasmapause region into the sub-auroral thermosphere/ionosphere system. A search of our multi-decade database of SAR arcs observed with an all-sky imager at Millstone Hill revealed that the brightest one occurred on the night of 29 October 1991. A new calibration of that event gives 9336 Rayleighs (R) as the brightness at 01:04 UT. Other regions of the SAR arc saturated the detector and so values above 10 kR probably occurred. A search of the published literature did not result in finding brighter SAR arc events. The surest way we know to check this is simply to claim that the above levels are the brightest ever observed, and then wait for objections! In this paper, we will present the extraordinary set of images obtained on this night, together with modeling results for the required electron temperatures.
DE: 2736 Magnetosphere/ionosphere interactions
DE: 2768 Plasmasphere
DE: 2788 Storms and substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2005 Joint Assembly