We present observations of the extended solar cycle activity in white-light coronagraphs, and compare them with the more familiar features seen in the Fe XIV green-line corona. We show that the coronal activity zones seen in the emission corona can b
e tracked high into the corona. The peak latitude of the activity, which occurs near solar maximum, is found to be very similar at all heights. But we find that the equatorward drift of the activity zones is faster at greater heights, and that during the declining phase of the solar cycle, the lower branch of activity (that associated with the current cycle) disappears at about 3 Ro. This implies that that during the declining phase of the cycle, the solar wind detected near Earth is likely to be dominated by the next cycle. The so-called rush to the poles is also seen in the higher corona. In the higher corona it is found to start at a similar time but at lower latitudes than in the green-line corona. The structure is found to be similar to that of the equatorward drift.
The onset of the Rush to the Poles of polar-crown prominences and their associated coronal emission is a harbinger of solar maximum. Altrock (Solar Phys. 216, 343, 2003) showed that the Rush was well-observed at 1.15 Ro in the Fe XIV corona at the Sa
cramento Peak site of the National Solar Observatory prior to the maxima of Cycles 21 to 23. The data show that solar maximum in those cycles occurred when the center line of the Rush reached a critical latitude of 76 +- 2{deg}. Furthermore, in the previous three cycles solar maximum occurred when the highest number of Fe XIV emission features per day (averaged over 365 days and both hemispheres) first reached latitudes 20 +- 1.7{deg}. Cycle 24 displays an intermittent Rush that is only well-defined in the northern hemisphere. In 2009 an initial slope of 4.6{deg}/yr was found in the north, compared to an average of 9.4 +- 1.7 {deg}/yr in the previous cycles. An early fit to the Rush would have reached 76{deg} at 2014.6. However, in 2010 the slope increased to 7.5{deg}/yr (an increase did not occur in the previous three cycles). Extending that rate to 76 +- 2{deg} indicates that the solar maximum in the northern hemisphere already occurred at 2011.6 +- 0.3. In the southern hemisphere the Rush to the Poles, if it exists, is very poorly defined. A linear fit to several maxima would reach 76{deg} in the south at 2014.2. In 1999, persistent Fe XIV coronal emission known as the extended solar cycle appeared near 70{deg} in the north and began migrating towards the equator at a rate 40% slower than the previous two solar cycles. However, in 2009 and 2010 an acceleration occurred. Currently the greatest number of emission features is at 21{deg} in the North and 24{deg}in the South. This indicates that solar maximum is occurring now in the North but not yet in the South.
The extended solar cycle 24 began in 1999 near 70 degrees latitude, similarly to cycle 23 in 1989 and cycle 22 in 1979. The extended cycle is manifested by persistent Fe XIV coronal emission appearing near 70 degrees latitude and slowly migrating tow
ards the equator, merging with the latitudes of sunspots and active regions (the butterfly diagram) after several years. Cycle 24 began its migration at a rate 40% slower than the previous two solar cycles, thus indicating the possibility of a peculiar cycle. However, the onset of the Rush to the Poles of polar crown prominences and their associated coronal emission, which has been a precursor to solar maximum in recent cycles (cf. Altrock 2003), has just been identified in the northern hemisphere. Peculiarly, this Rush is leisurely, at only 50% of the rate in the previous two cycles. The properties of the current Rush to the Poles yields an estimate of 2013 or 2014 for solar maximum.
