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Changing Sun

StarDate: 
September 14, 2019

The Sun is going through a big change. One cycle of activity is ending, while another is just beginning. Neither cycle is very active, though. In fact, the Sun probably is entering an unusually quiet year. There may be times when we won’t see anything going on at all.

The Sun follows a magnetic cycle that reaches its peak every 11 years or so. At the peak, the Sun produces lots of the dark magnetic storms known as sunspots. It also produces more outbursts of energy and particles.

Right now, the Sun is at the end of one cycle and the start of another. The ending one has been well below normal. In fact, there were many days where astronomers saw no sunspots at all. And the next cycle is expected to be even calmer.

Hints of the new cycle were seen as early as 2016. But the first strong indication came this July. A sunspot that lasted for a few days had the opposite magnetic polarity of the previous ones — a sure sign that it belongs to a new cycle.

For the next year, though, we’re expected to remain at solar minimum — a time when the Sun is especially quiet.

Solar minimum is a good thing for our technology. Solar storms can harm satellites, force airlines to reroute flights, and knock out power grids on Earth. That’s less likely to happen during solar minimum — although individual storms can still be nasty.

The new cycle should begin to ramp up by late next year, and reach its peak a few years later — one more change for our always-changing star.


Script by Damond Benningfield

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