HR: 0800h
AN: SH21C-0439    [Abstracts]
TI: Timing accuracy and variability of the planar propagation of magnetic field structures in the solar wind
AU: * Ober, D M
EM: Daniel.Ober@atk.com
AF: ATK Mission Research, 589 W. Hollis St., Suite 201, Nashua, NH 03062 United States
AU: Weimer, D R
EM: Dan.Weimer@atk.com
AF: ATK Mission Research, 589 W. Hollis St., Suite 201, Nashua, NH 03062 United States
AU: Maynard, N C
EM: Nelson.Maynard@atk.com
AF: ATK Mission Research, 589 W. Hollis St., Suite 201, Nashua, NH 03062 United States
AU: Collier, M R
EM: Michael.R.Collier@nasa.gov
AF: NASA Goddard Space Flight Center, Code 692, Interplanetary Physics Branch, Building 21, Room 246, Greenbelt, MD 20771 United States
AU: McComas, D J
EM: DMcComas@swri.edu
AF: Southwest Research Institute, Space Science and Engineering Division, P.O. Drawer 28510, San Antonnio, TX 78228 United States
AU: Smith, C W
EM: Charles.Smith@unh.edu
AF: University of New Hampshire, Institute for Earth, Oceans and Space, Room 207 Morse Hall, 39 College Road, Durham, NH 03824 United States
AB: The propagation time of the interplanetary magnetic field (IMF) from an upstream monitor to the magnetosphere may be significantly different from what would be predicted using the advection delay time at the solar wind velocity. This influences our ability to correlate magnetosphere-ionosphere phenomena with solar wind variations. Earlier studies revealed that variable lag times and tilted propagation planes in the IMF could account for this timing difference. Using 3 or more satellites the time varying orientation of the tilted propagation planes can be determined. Alternatively, the time varying plane orientations can be derived with data from a single spacecraft using a modified minimum variance approach. The validity of the derived planes for describing the structure and propagation of the IMF is evaluated by predicting the IMF observations at the location of an additional spacecraft not used in the calculation of the time varying plane orientations. The range of orientations and temporal variability of the propagation planes will be presented for several cases, comparing the 3-spacecraft solution with the single spacecraft solution. The orientation of the time varying propagation planes is observed to vary over a wide range of angles with time scales of 10's of minutes.
DE: 7524 Magnetic fields
DE: 2134 Interplanetary magnetic fields
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting