Having examined the observations that had accumulated over half a century, Japanese scientists found out that the microwaves coming from the Sun at the minima of the last five cycles were the same, although the maxima were very different.
In Japan, continuous 4-frequency solar microwave observations began in 1957 from the Atmospheric Research Institute of the University of Nagoya. In 1994, telescopes were transferred to the campus of the Noahay NAOJ.
Researchers analyzed over 60 years of data and found that cycle minima converge each time. This is an important step in the study of our star, because it is difficult to deduce laws beyond the limits of one cycle (lasts 11 years).
Often the solar cycle is associated only with the number of spots on a star, but there are other manifestations of solar activity. Therefore, counting stains is not enough. Another important indicator is microwaves. Moreover, they can be observed on cloudy days.
