The sun constantly cycles between periods of activity and periods of inactivity, and a new technique allows scientists to better predict when things will start getting interesting.
Humanity has been tracking sunspots for millennia, and over the past two hundred years we’ve noticed a pattern: a strange but regular 11-year cycle that constantly repeats from a maximum phase with lots of sunspots to a minimum phase with barely any sunspots at all.
Currently, we’re near a minimum, which is a good thing. The presence of sunspots indicates that the sun is in a foul mood, with its strong magnetic fields twisted and gnarled up, ready to snap free, releasing a torrent of energy in the process.
When that happens, the sun might launch a flare – a burst of high-energy radiation – or a prominence might leap from the surface. In the worst bouts, the sun can set off a coronal mass ejection, a massive plume of plasma sun-stuff slurped up from the sun itself and sent hurtling across the solar system.
When these ejections are aimed for the Earth, we have to shut down satellites and bring astronauts in from spacewalks, as the intense electromagnetic forces can mess with exposed circuitry and electronics.
Even down here on the surface of our planet, with our thick atmosphere and strong magnetic field protecting us, we are vulnerable. The worst storms can disrupt electrical grids and worse.
Sun spotting
Space weather is serious business, and predicting when the sun will get temperamental is critical for our space industry.
Recently, a team of researchers at the University of Warwick published in Geophysical Research Letters a new approach to monitoring the sun. By combing through the past two centuries of sunspot data and applying some fancy mathematical tricks, they can identify when the sun is ready to switch from a minimum and start ramping up.
They made a solar clock, allowing them to predict the likelihood of solar storms becoming more frequent. While they can’t say exactly when the next storm will happen, they can say when they will be more common, and they predict that we will reach another solar maximum in the mid-2020’s.
And we better hold on.
Solar flares can happen any time, though more likely at SS maximum. High solar activity (without flares) is considered a good thing by radio amateurs because it greatly boosts ionospheric radio propagation on Earth.
Roughly predicting a solar maximum is easy. The 11 year cycle is fairly regular. Predicting its magnitude is the hard part. They vary a lot.
Which activity, I’m tempted to say “of course”, coincide with the politically set target date for the Artemis Moon landing attempts.