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The Suns variability is controlled by the progression and interaction of the magnetized systems that form the 22-year magnetic activity cycle (the Hale Cycle) as they march from their origin at $sim$55 degrees latitude to the equator, over $sim$19 years. We will discuss the end point of that progression, dubbed terminator events, and our means of diagnosing them. Based on the terminations of Hale Magnetic Cycles, we construct a new solar activity clock which maps all solar magnetic activity onto a single normalized epoch. The Terminators appear at phase $0 * 2pi$ on this clock (by definition), then solar polar field reversals commence at $0.2 * 2pi$, and the geomagnetically quiet intervals centered around solar minimum, start at $0.6 * 2pi$ and end at the terminator, lasting 40% of the normalized cycle length. With this onset of quiescence, dubbed a pre-terminator, the Sun shows a radical reduction in active region complexity and (like the terminator events) is associated with the time when the solar radio flux crosses F10.7=90 sfu -- effectively marking the commencement of solar minimum conditions. In this paper we use the terminator-based clock to illustrate a range of phenomena associated with the pre-terminator event that further emphasize the strong interaction of the global-scale magnetic systems of the Hale Cycle.
The cyclic, enigmatic, and ubiquitous magnetism of the Sun provides the energy we need to survive and has the ability to destroy our technologically dependent civilization. Never before has understanding solar magnetism and forecasting its behavior b
The Sun provides the energy necessary to sustain our existence. While the Sun provides for us, it is also capable of taking away. The weather and climatic scales of solar evolution and the Sun-Earth connection are not well understood. There has been
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We investigate the characteristics and the sources of the slow (< 450 km/s) solar wind during the four years (2006-2009) of low solar activity between Solar Cycles 23 and 24. We use a comprehensive set of in-situ observations in the near-Earth solar