Astrophysics and Space Sciences Transactions www.astrophys-space-sci-trans.net 1810-6528 1810-6536 4 1 2008 10.5194/astra-4-19-2008 http://www.astrophys-space-sci-trans.net/4/19/2008/ http://www.astrophys-space-sci-trans.net/4/19/2008/astra-4-19-2008.html http://www.astrophys-space-sci-trans.net/4/19/2008/astra-4-19-2008.pdf 19 26 2008-05-30 The Heliospheric Magnetic Field over the Hale Cycle N. A. Schwadron M. Owens N. U. Crooker Boston University, Center for Space Physics, Center for Integrated Spaceweather Modeling, 725 Commonwealth Ave, Boston MA, 02215, USA The concept that open magnetic flux of the Sun (rooted with one and only one footpoint at the Sun) is a conserved quantity is taking root in the heliospheric community. Observations show that the Sun's open magnetic flux returns to the baseline from one solar minimum to the next. 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