Our Sun has had a rather calm year, apart from the problems of planet Earth. A careful examination of its activity verifies what solar aficionados have long suspected: the cycle of our nearest star has begun again.
Humans have seen a pattern of quiescence and temper that repeats about every 11 years ever since we began to watch the Sun's black spots in earnest.
Since the first observations were made in the middle of the eighteenth century, there have been 24 of these cycles. And the beginning of number 25 began in December 2019, according to a team of scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA).
You are not to fault for failing to notice the change. There were no cosmic trumpets or lightening strikes. only the emergence in high latitudes of low-temperature shadows known as sunspots.
According to Frédéric Clette, head of the World Data Center Sunspot Index and Long-term Solar Observations, "We preserve a precise record of the few small sunspots that indicate the commencement and ascent of the next cycle."
"These are the little precursors of the enormous solar explosions of the future. We can only identify the turning point between two cycles by monitoring the overall trend over a long period of time."
In reality, it is hard to see a new start until it has gone due to fluctuations in the Sun's behaviour. It required poring through data on solar activity from the previous eight months to determine that last year was the most monotonous the Sun would be for the next ten years.
Despite meticulously documenting these 11-year cycles for millennia, we still don't completely understand the underlying mechanics. When you gaze out into the Universe, you will observe a wide range of pulsing objects that seem to flare and darken at intervals you could practically set your watch by. Periodicity in stars is rather frequent.
The patterns of our own Sun are best explained by variations in its magnetic fields, which are in turn influenced by intricate plasma currents that move deep beneath.
There is a desire to associate it with a similar periodicity in planetary orbits, but the part we need to figure out is exactly what pushes and pulls these currents in such a regular fashion.
It's crucial to keep in mind that solar activity never ceases; it only changes shape as the pendulum swings, according to NASA solar scientist Lika Guhathakurta, as we leave the solar minimum and go closer to Cycle 25's peak.
Although the cycle of peaks and valleys lasts for 11 years, it is really a reflection of a longer cycle that lasts 22 years and is characterised by a full reversal in the Sun's polarity. The poles switch positions every 11 years and then revert at the conclusion of the next cycle.
Monitoring these changes may improve our ability to anticipate space weather, which is mostly determined by furiously blowing forth bursts of charged plasma and radiation, particularly during solar maximums.
Before we can officially declare that we are in the midst of the Sun's most aggressive phase, it will likely be another five years. That doesn't mean we shouldn't pay attention right now, however.
It remains to be seen whether Solar Cycle 25 will put up a show or not, but it is unlikely to be explosive. In spite of this, number 24 was quite tranquil, primarily in contrast to the cycles that came before it, which were a little stronger than typical.
Doug Biesecker, co-chair of the panel and solar physicist at NOAA's Space Weather Prediction Center in Colorado, argues that just because the solar cycle is below normal doesn't imply there is no possibility of severe space weather.
"The Sun has a real and present influence on our everyday existence."
It also pays to be honest about the extent of that influence, particularly if you're not a space engineer overseeing a fleet of sensitive satellites or an astronaut worried about soaking up high-speed protons and X-rays.
Solar cycles are hardly audible down here on the surface, protected by miles of atmosphere. Occasionally, at solar maximums, aurora activity may slightly increase, but most of the time, we don't need to worry that a solar flare would end the world as we know it.
There is little doubt that any connections between the rather gloomy events of 2020 and the Sun's reflective attitude are, at best, symbolic. But sometimes, it's impossible to not but wonder what the stars are contemplating.
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