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Causes and Effects of Superstorms Associated with the Magnetic Field in the Corona and the Heliosphere. J. Todd Hoeksema Stanford University. Premonition of Activity. 14 Days Before CMP!. Observations of Regions 486 & 488. 14D Before. Central Meridian. 14D Later. Far Side.
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Causes and Effects of SuperstormsAssociated with the Magnetic Field in the Corona and the Heliosphere J. Todd Hoeksema Stanford University
Premonition of Activity 14 Days Before CMP!
Observations of Regions 486 & 488 14D Before Central Meridian 14D Later Far Side
The Coronal Response Tom Bridgman NASA/Goddard Space Flight Center Scientific Visualization Studio
Several Rotations -3 +1 -1 +2 +6 0
Did the open field line connections change? Thanks to Yang Liu at Stanford For the following figures
Evolution of magnetic field in this period Central meridian: CR2007_290** degree in Longitude (Sept. 4) Central meridian: CR2008_290** degree in Longitude (Oct. 1) 0464 0488 Central meridian: CR2009_290** degree in Longitude (Oct. 28) 0484 0486 Central meridian: CR2010_290** degree in Longitude (Nov. 25) 0501 **Not usual 180 centering
Evolution of magnetic field in this period Central meridian: CR2007_290 degree in Longitude (Sept. 4) Central meridian: CR2008_290 degree in Longitude (Oct. 1) 0464 0488 Central meridian: CR2009_290 degree in Longitude (Oct. 28) 0484 0486 Central meridian: CR2010_290 degree in Longitude (Nov. 25) 0501
AR0464 (0484, 0501) and large-scale magnetic field CR2007:290: Sept 4 CR2008:290: Oct 1 0464 0464 0464
AR0486, AR0488 and large-scale magnetic field CR2008:290: Oct 1 CR2009:290: Oct 28 0488 0486
Extremely fast halo CMEs and active regions AR0486, together with AR0488, produced a big open field area after they emerged. AR0464 (a.k.a. 0484, 0501) emerged within/close to an area with large-scale open magnetic field . ? The active regions associated with these high speed halo CMEs are closely associated with sources of already open magnetic flux, except AR0498. In this way the open magnetic field provides an avenue for CMEs to blow out.
AR0498 and large-scale magnetic field CR2009:160 0498
Conclusions • The photospheric field changed dramatically in CR 2009; October 2003 • Numerous dramatic high-speed CME’s blasted through the corona and heliosphere • New flux emerged in such a way as to reinforce the existing structure • New open flux regions had easy access to the heliosphere • The ambient large-scale structure of the heliospheric current sheet changed very little! • This is consistent with earlier results of Zhao & Hoeksema, JGR, 1996.