The Sun Is Going Through a Quiet Phase but We Probably Won't Freeze to Death

It's generating fewer sunspots and less energy.

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Cultura RM/Janeycakes Photos/Getty Images

Shhh … the sun is sleeping. Or maybe it’s just micronapping. In any case, scientists say our favorite star is going through an uncharacteristic quiet spell.

While NASA is quick to point out that we shouldn't expect a mini-Ice Age, the space agency notes the sun has been generating less energy over the last year or so. Sunspots, too, have declined. Those are the dark circles of cooler temperatures that burst from the atmosphere, typically as a result of fluctuations in the sun’s magnetic field.

They’re also a good marker of how ornery our star happens to be at a given time. And these days, it seems to have taken a rare turn for the silent, smouldering type.

But if the sun is chilling, by extension, shouldn’t we be too? In fact, the last time the Earth caught a chronic chill was in the late 17th Century, when the planet’s northern hemisphere fell into a Little Ice Age, and temperatures tumbled about 2 degrees Celsius. It lasted until 1715 and coincided with a prolonged solar slumber.

Another Ice Age?

Fortunately, scientists suspect the sun is taking more of a mini-vacation. In fact, our star follows a fairly predictable schedule, alternating cycles of high and low activity about every 11 years. During a busy cycle, the sun is all bluster: coronal mass ejections, solar flares and plenty of those aforementioned sunspots.

But the sun, scientists say, is just emerging from its 24th recorded cycle — a long, lethargic stretch called a solar minimum.

"There's been this steady decline," astrophysicist David Hathaway tells CBC News. "I'm fairly confident looking at our own predictions and predictions of others, that cycle 25 is going to be another small cycle."

But there' a chance, if the sun doesn’t perk up during what’s supposed to be an active cycle, then we may experience a "grand solar minimum," LiveScience reports. Basically, the sun could hit the snooze button for decades, if not centuries. Not only would that result in fewer sunspots, but less UV radiation reaching Earth.

That Time When the King's Beard Turned to Ice...

A drop by a couple of degrees may not sound like a lot, but consider the downright eerie events of the last Little Ice Age.

“Birds iced up and fell from the sky; men and women died of hypothermia; the King of France’s beard froze solid while he slept,” John Lanchester writes in the New Yorker.

Still, if the sun really does decide to stay in bed a little longer this time, it probably won’t be as cold here as the last time. Mostly, because things have changed a lot here on Earth since the last sun-snooze.

"The warming caused by the greenhouse gas emissions from the human burning of fossil fuels is six times greater than the possible decades-long cooling from a prolonged Grand Solar Minimum,” NASA notes in its blog. "Even if a Grand Solar Minimum were to last a century, global temperatures would continue to warm. Because more factors than just variations in the Sun's output change global temperatures on Earth, the most dominant of those today being the warming coming from human-induced greenhouse gas emissions.”

Our Sun is a Very Chill Star

The thing is, our home star has always been a bit of a celestial slacker. In a recent study, astronomers compared the brightness of our sun over time with data gathered on other stars. They found most stars resembling our own are much more volatile. And over the last 9,000 years, they note, our sun has been particularly quiet.

“These stars are similar in every way we can measure to the sun, but many of them show variability up to five times higher than the sun, which was surprising,” study co-author Timo Reinhold at the Max Planck Institute for Solar System Research told New Scientist. “One possible conclusion would be that there is some yet-unidentified quality of these stars that we don’t know that is different from the sun.”

Just keep in mind that "quiet" is relative when we’re talking about a ball of plasma that’s constantly wailing. As one heliophysicist put it, “Imagine 10,000 Earths covered in police sirens, all screaming.”

Now, that’s the ornery orb we all know and love.