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The Russian TESIS/ CORONAS-PHOTON Solar Observatory, which has been working in orbit since January 30th, 2009, has photographed one of the most important events in the build up to the upcoming solar cycle - the formation of our star's new southern belt of activity. The first magnetic fields of the new cycle in the southern hemisphere appeared on the Sun's surface on May 23-24th. The emerged areas have a typical NS-configuration, i.e. they have fields of opposing polarities, positioned along the line of solar latitude. Predictably, fields with positive polarity are displaced to the West along the entire southern belt, and negative fields are displaced to the East. Therefore, polarity reversal of magnetic fields has occurred in the Sun's southern hemisphere, and a new magnetic configuration has been formed, which will now remain intact for the whole future cycle.
The belt of activity is one of the primary concepts, characterizing the solar cycle. It indicates that active phenomena on the Sun occur not in random places, but are localized in quite narrow zones, surrounding the Sun in parallel to its equator. According to the modern theory, there should be two such belts in each cycle. One of them passes above the equator at a latitude of approximately 30 degrees, i.e. it is situated in the Sun's northern hemisphere, and the second should be symmetrically positioned in the Sun's southern hemisphere.
The formation of the first of two belts of activity (the northern belt) occurred on the Sun at the end of March this year. It initiated a whole series of events connected with solar activity, which took place over the following two months: the first flashes of the new cycle, the formation of this year's largest mass ejections, and the formation of the first powerful active areas. However, all these phenomena occurred in the northern hemisphere and did not affect areas south of the Sun's equator, which continued to remain in a state of "deep hibernation".
And now, after two years of prolonged minimum, the solar "winter" seems to be over not only in the North, but also in the South of the Sun. At the present time, the emerged southern fields are already actively beginning to warm up the corona. This has led to a local rise in coronal temperature (up to 5 million degrees) and a noticeable increase in luminosity (in a deep ultraviolet range). "Flares" - bright areas, which usually precede the formation of sunspots - have started to form on the Sun's visible surface.
However, the radiation flux of areas in the x-ray range, where solar flares are usually measured, is so far insignificant. This means that we will have to wait at least a month for the formation of the first flashes in the Sun's southern hemisphere - until the areas of the new belt have completed one full rotation around the Sun's axis and have once again returned to the Earth's field of vision, having become "stronger".
However, the new belt of activity can either become stronger or collapse. The current solar cycle is extremely unpredictable and it is quite possible that we will witness more surprises in the future.
Meanwhile, we can admire a unique situation from the Earth. Currently, active areas belonging to three different magnetic belts are all simultaneously visible in the solar corona. This year's two largest active areas, formed in the northern hemisphere, are moving up and "over the horizon". The active area of the old solar cycle, which still doesn't want to lose its position, remains "blazing" on the equator. And, finally, the magnetic fields of the new southern belt of activity are forming and gaining strength below. Areas of all three belts will be visible until May 27th, and they may come together again on June 20-25th, i.e. after one full rotation of the Sun.
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