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MHD-prediction of the solar corona at the total solar eclipse of 2009 July 22

To make predictions on the shapes of the solar corona to be observed at the total solar eclipse of 2009 July 22, we are conducting the daily MHD simulations to obtain the time-relaxed (quasi-)steady state of the sub/trans-Alfvenic solar corona, using the solar photospheric magnetic field data as the boundary values. The solar photospheric magnetic field data used here are made by SOHO/MDI and updated daily, with polar field corrected. The simulation is conducted on daily basis, using the magnetic field data made two days before the simulation. Essentially, the procedures are identical to those used in our daily MHD simulations.
   The plots below show some features of the simulated solar corona. The left box shows the line-of-sight integration of the synthetic coronal density, normalized in accordance with the Newkirk-filter function with in 5 Rs, and the simulated open-field regions (dark gray). The right one does the field lines nearby the plane-of-sky and the radial component of the solar surface boundary magnetic field (Br ; blue/red for away from/toward the Sun). The point of view is fixed at the Earth's potion on July 22, and the P-angle (geocentric angle between solar north pole and Earth's north pole) is taken into account to make the plots matching the ground observation. The date of computation appears at the upper right, and the date of the solar surface field measurement is two days before that date.

total solar eclipse 2009 The boundary treatment "choice A" (see daily MHD simulations for details) is applied to determine the MHD variables on the sub-Alfvenic solar surface. Click here(mpeg;1.3MB) to view the animation showing how the predicted synthetic corona will "evolve".
total solar eclipse 2009 Essentially, same as above but a different boundary treatment "choice AB" is applied instead of choice A. The animation(mpeg;1.3MB) is available.

modified: July 6, May 29, 2009
K. Hayashi