J. Todd Hoeksema Stanford University
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DESCRIPTIONCauses 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. - PowerPoint PPT Presentation
Causes and Effects of SuperstormsAssociated with the Magnetic Field in the Corona and the HeliosphereJ. Todd HoeksemaStanford University
Premonition of Activity14 DaysBeforeCMP!
Observations of Regions 486 & 48814D BeforeCentral Meridian14D LaterFar Side
The Magnetic Field
Another View of the Surface
The Coronal ResponseTom BridgmanNASA/Goddard Space Flight Center Scientific Visualization Studio
The Heliospheric Field
The Heliospheric Field
Did the open field line connections change?Thanks to Yang Liu at StanfordFor the following figures
Evolution of magnetic field in this periodCentral meridian: CR2007_290** degree in Longitude (Sept. 4)Central meridian: CR2008_290** degree in Longitude (Oct. 1)Central meridian: CR2009_290** degree in Longitude (Oct. 28)Central meridian: CR2010_290** degree in Longitude (Nov. 25)**Not usual 180 centering
Evolution of magnetic field in this periodCentral meridian: CR2007_290 degree in Longitude (Sept. 4)Central meridian: CR2008_290 degree in Longitude (Oct. 1)Central meridian: CR2009_290 degree in Longitude (Oct. 28)Central meridian: CR2010_290 degree in Longitude (Nov. 25)
AR0464 (0484, 0501) and large-scale magnetic fieldCR2007:290: Sept 4CR2008:290: Oct 1
AR0486, AR0488 and large-scale magnetic fieldCR2008:290: Oct 1CR2009:290: Oct 28
Extremely fast halo CMEs and active regionsAR0464 (a.k.a. 0484, 0501) emerged within/close to an area with large-scale open magnetic field .AR0486, together with AR0488, produced a big open field area after they emerged.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 fieldCR2009:160
ConclusionsThe photospheric field changed dramatically in CR 2009; October 2003Numerous dramatic high-speed CMEs blasted through the corona and heliosphereNew flux emerged in such a way as to reinforce the existing structureNew open flux regions had easy access to the heliosphereThe ambient large-scale structure of the heliospheric current sheet changed very little!This is consistent with earlier results of Zhao & Hoeksema, JGR, 1996.