How Do Sunspots Work?

0:00This is an I Heart Podcast. Guaranteed Human

1:00This episode is brought to you by the Health Versus Hype Podcast. We've all tumbled down an internet rabbit hole trying to self-diagnose, and it leaves us more anxious than informed. Our feeds are full of wellness trends, but how do we know what's real, what's exaggerated, and what's just wrong? Health Versus Hype from the American Medical Association breaks it all down. A man nominated science communicator Trastomingo talks to doctors, influencers, and real people trying these trends. I'm not to cancel them, but to understand them. Because when it comes to your health, who will you listen to matters? So listen to Health Versus Hype, wherever you get your podcasts. If you like YouTube, you'll love YouTube Premium. Hi, I'm Sean Evans from Hot Ones, and I want to tell you about YouTube Premium. It has offline downloads, so you can watch without Wi-Fi, background play, so you can lock your phone, and it still plays baby. Oh, and it is completely ad-free.

2:02Yes, I said it ad-free. Try YouTube Premium for two months free at youtube.com slash premium. Trial eligibility varies, terms apply, cancel anytime. This message is brought to you by Apple Card. The fall season always brings its fair share of surprises, like the first snowfall or a late night trip to the store for your kids' school project. No matter what the season brings, Apple cards got you covered. You can earn 2% daily cash back when you use Apple Card with Apple Pay. Apply for Apple Card now, and use it in minutes with Apple Pay. Subject to Credit Approval, Apple Card is issued by Goldman Sachs Bank USA Salt Lake City Branch. Terms and more at applecard.com. Santa Claus is coming to town in the home depot as everything you need to launch your holiday season in style. Upgrade your yard with this season's hottest decor, including the show-stopping towering Santa and his impressive reindeer, both 8.5-foot tall and both designed with incredible detail that stands out day or night.

3:05Create a holiday display that turns heads, spark smiles, and becomes the neighborhood favorite with decor that delivers impact. Make your home Santa's favorite stop, but the holiday decor you want all waiting for you at the Home Depot. Welcome to Brain Stuff, a production of iHeart Radio. Hey, Brain Stuff, Lauren Volkobom here. Sunspots. The ancient Chinese referred to them as stars inside the solar orb. One Renaissance astronomer argued that they were actually undiscovered planets. Today, some believe their appearance is linked to waves of UFO sightings and paranormal activity. The rest of us wonder if they're the reason for our dropped calls or a spotty radio or internet service. Sunspots are the peculiar dark spots that pop up regularly on the surface of the sun. They usually appear in pairs or in groups called belts on either side of the sun's equator between about 40 degrees and 50 degrees latitude, both north and south.

4:10Sunspots vary tremendously in size, ranging from less than 200 miles across that's 30 kilometers to many times larger than Earth. Small sunspots may last for less than an hour, but larger ones can last up to six months. Some are big enough to be seen by the naked eye. Keep in mind, of course, that staring directly at the unfiltered sun is an extremely bad idea because it can permanently harm your eyes. Side note here, yes, seriously. You can observe the sun and its spots safely by using solar viewing glasses or eclipse glasses. Or, if you have a telescope or binoculars, you can fit them with a specialized solar filter meant for observation. Or, if you don't have any of those on hand, you can always use a pinhole projector, a punch a hole in a stiff piece of paper, and with the sun at your back, project an image of it onto another surface like a wall or another piece of paper. Do not mess around with the sun. It will win.

5:13Anyway, a sunspot's appear dark to us when viewed safely because they're cooler in temperature than these surrounding areas on the sun's visible surface. This is called the photosphere, and it has a temperature of about 10,000 degrees Fahrenheit or around 5,500 Celsius. The dark interior of a sunspot can be about 40% cooler than the rest of the sun's surface. A sunspot's are cooler because there are areas of intense magnetism, so intense that it inhibits the flow of hot material from the sun's interior to its surface. Sunspots occur because the sun isn't a hunk of rock like Earth, but a ball of continually circulating plasma, that is hot electrically charged gases, that doesn't move in one piece. The interior and exterior of the sun rotates separately, and the exterior rotates more quickly at the equator than at the North and South poles.

6:13Point on the equator will only take 25 Earth days to go around, while a point near one of the poles could take 36. Over time, all of that messy and uneven movement twists and distorts the sun's main magnetic field in the same way that your bed sheets get wrinkled and bunched up when you toss and turn in your sleep. The bunched up spots, the twists in the magnetic field lines, have so much magnetic power that they push on the circulating plasma beneath them and prevent its heat from rising directly to the surface. In other words, they become sunspots. The cooler sunspots appear darker, and the plasma blocked by them will flow into the areas surrounding them, making those even hotter and brighter than normal, thus making the sunspots stand out even more. I should say here that sunspots are still objectively very bright, about as bright as the full moon. The average sunspot is about as big as our planet, but the biggest on record, which appeared in 1947, was about 18 times as large as the whole surface area of the Earth.

7:21Due to the size of the sun, despite the slow speed of its surface rotation, a sunspot will appear to move across its surface about four times faster than a point on Earth would appear to move from space. In London, the Royal Observatory granite has kept detailed records of the size and location of sunspots since 1874. Roughly every 11 years, the number of sunspots increases from nearly zero to more than 100, then decreases to near zero again as a new cycle starts. This pattern is called the sunspot cycle. Since the 1700s, sunspot cycles have varied in length between 9 and 14 years. At the beginning of the cycle, sunspots form in the sun's mid-latitudes, but as the cycle progresses, they occur closer to the equator. We think the cycle occurs because the sun contains a sort of conveyor belt that circulates plasma between the sun's equator and its poles and then back again over a period of years.

8:23The idea is that when sunspots that formed early in a sunspot cycle begin to decay, they leave a kind of magnetic imprint on the moving plasma beneath them. The conveyor belt carries that plasma with those magnetic imprints towards the poles and then back inside the sun. The magnetic fields within the sun are then distorted and intensified even more before the conveyor belt sends the plasma to resurface near the equator. There, the plasma forms new, even more powerful sunspots. During any given sunspot cycle, activity usually rises quickly and then declines gradually. The point where sunspots reach their peak of intensity is called the solar maximum and the low point the solar minimum. Solar minimums usually last for several years, but they sometimes go on for much longer. For example, there was a 60-year period between 1650 and 1710 when there was little or no sunspot activity at all.

9:24This is called the Monder minimum after the astronomer who discovered it. The cause remains a mystery, though some astronomers theorized that it's normal for stars to occasionally go through such long dormant periods. At the solar maximum, the sun's magnetic poles actually flip. Like Earth, the sun has North and South magnetic poles around the solar minimum anyway. They get increasingly complex throughout the cycle until at the height of solar activity every 11 years or so, they flip. So, sunspot activity is actually part of a 22-ish year cycle in which the sun's poles flip and then revert, called the Hail Cycle. All of this is a subject of interest, not just because sunspots are cool. Literally, but also because of sunspots potentially disruptive effects on power grids and radio-based communications here on Earth. And we're going to get into that, but first we're going to get into a quick break forward from our sponsor.

10:29If you're ready to feel confident again, visit OrderlyMeds.com to learn about which GLP1 you may be eligible for. Getting started as fast, easy, and happens virtually through telemedicine from licensed professionals. Game confidence, choose healthy habits this fall. Check it out for yourself. Go to OrderlyMeds.com. That's OrderlyMeds.com. Taking care of yourself feels great. Compounded medications are not FDA approved. Electoral Lady required an internment by a licensed provider. Individual results may vary. See website for details. Every woman has one. The nightgown she refuses to get rid of. It's from a different decade. A different address. Honestly, a different size. And it is still the softest thing she owns. That's an Eileen West. 50 years of nightgowns and robes in fine cotton lawn with lace and pin tucks and stitching that doesn't give up. They get washed a thousand times and get softer. They get worn through a whole chapter of a life and stay for another.

11:32So stop wearing the one that doesn't fit and go get the one that does. EileenWest.com. Pick a nightgown. Pick your size. And it ships free over $100. The one you'll keep for the next 20 years is at EileenWest.com. Eileen West. Loved by generations of women. Okay, sunspots are connected with other solar events like flares and coronal mass ejections or CMEs. A solar flare is a sudden release of energy from the sun and CMEs actually shoot hot plasma from the sun into space. We don't know exactly what triggers them, but the bigger the group of sunspots that appears, the more intense such solar weather tends to be. Flares and CMEs can send enormous amounts of energy and charged particles hurtling into collision with Earth's atmosphere. Here, they can cause magnetic storms that create beautiful auroras, but also disrupt or alter radio and cell phone communication and can wreak havoc with satellite electronics and Earth-bound electrical grids.

12:43For example, during the solar maximum of 1989, a power surge triggered by solar energy damaged transformers that were part of the hydro-Cabec power system. That surge left 6 million people in Canada and the northeastern US without electricity for more than 9 hours. The increase in radiation that accompanies a solar flare is a theoretical health hazard to spacewalking astronauts, so researchers monitor solar activity and can call for delays of work outside of spacecraft until the danger is passed. Some people have theorized that there's also a link between solar weather and changes in Earth's climate, perhaps instead of climate change being driven by human industry and agriculture. It is true that our climate is influenced by a lot of complex factors, but research has shown that the solar cycle's effect is marginal compared with human influence, unlike the emission of greenhouse gases. Oddly, sunspot activity can actually help ham radio reception, because the increased radiation causes the atmosphere to bend higher radio frequencies back toward Earth.

13:53The ways in which solar weather can affect us here on Earth deserves its own episode or episodes, and that's all on my list. But long before people were worried about power grids, radio transmissions and global warming, they were watching sunspots. Ancient Chinese and Greek astronomers recorded their observations of sunspots over 2,000 years ago. A thousand years ago, records from Korea map sunspots too, and a myth out of Central Mexico tells of a sun god with a pockmarked face, perhaps implying sunspot observations. However, while other peoples continued their records over the centuries, there was a bit of a gap in Europe. For a long time, just about everyone there accepted the Greek philosopher Aristotle's idea that the heavens were perfect and unchanging. This included the Catholic Church, which considered heavenly bodies to be extensions of divine perfection.

14:53So, for example, when a large sunspot appeared for 8 days in 807 CE, they dismissed the phenomenon as the passage of the planet Mercury across the sun. In 1611, descriptions of sunspots started showing up in European literature again, from Galileo Galilei and three other astronomers spread across the continent, thanks to the development of telescopes in 1608. Back then, people would rely on Earth's atmospheric conditions, like a decent fog or a cloudy haze, especially around sunrise or sunset, to observe the sun directly. And astronomers used a pinhole projection technique, just like we might today, to restrict the light hitting a mirror or a telescope and then study the projection. One of those astronomers of 1611, Jesuit priest by the name of Christoph Scheiner, tried to come up with an explanation that didn't contradict the Church's teachings. So, he argued that the spots were undiscovered planets that orbited very close to the sun.

15:58Galileo correctly figured out that sunspots were part of the sun itself, perhaps clouds he thought, by closely studying their movement as they neared the edge of the sun's visible surface. By the mid-1700s, European astronomers were recording and compiling their observations of sunspots on a daily basis. As scientists accumulated more and more data, they began to notice that sunspot activity ebbed and flowed in a pattern. In 1843, astronomer S. H. Schwab was the first to describe the 11-year sunspot cycle. Since then, researchers have used an array of tools to learn more, including giant solar telescopes that were specially cooled to observe the sun's light without being distorted by its heat. In 1908, astronomer George Ellery Hale discovered sunspots magnetic nature, and used that discovery to prove the existence of a large magnetic field in the sun's interior.

16:58That aforementioned 22-year hail cycle is named after him. More recently, astronomers discovered star spots, that is, sunspots on other stars. Hundreds of other star spots have been recorded. One giant star in the constellation Triangulum bore a spot 10,000 times larger than the biggest spots ever observed on our sun. Researchers think that some younger stars might be so covered in star spots that they affect the stars of a overall temperature, which means that our prior assumptions about those star sizes could be wrong. As of this recording, in fall of 2026, we're in the middle of the 25th solar cycle since researchers started tracking them. It started with a solar minimum in 2019, and the peak of the cycle is already past us. It started in 2024 and was accompanied by unusually wide spread auroras. Activity will continue decreasing through the anticipated end of the cycle in 2030.

18:01But that doesn't mean we won't necessarily see some spectacular sunspots in the near future. You can follow along with solar changes at sites like spaceweather.gov, which is the Space Weather Prediction Center of the National Oceanic and Atmospheric Administration. They shared daily data, including images of the solar weather, warnings for when it might affect us, and forecasts for aurora here on Earth. Today's episode is based on the article, How Sun Spots Work, on How Stuff Works.com, written by Patrick J. Kiger. Brain Stuff is a production of iHeart Podcasts in partnership with How Stuff Works.com, and is produced by Tyler Klein. Before more shows for my heart podcasts, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.

19:02Ready to feel energized and in control again? At Orderly Meds, we have helped thousands just like you take charge of their health with a GLP1. If you've tried dieting, exercising, and relying on willpower and nothing seems to stick, then it might be time to talk to a licensed provider about your options. That's what Orderly Meds is for. This fall, choose healthier habits for yourself with a visit to OrderlyMeds.com. You don't need to visit with a physician in person to become eligible. Orderly Meds has a simple, virtual process, connect with licensed medical professionals who can determine whether a GLP1 treatment may be appropriate for you wherever you are. Get started from the comfort of home online. Change your habits and consider a new approach to feeling your best. Visit OrderlyMeds.com to learn more. That's OrderlyMeds.com. OrderlyMeds.com. Game confidence and choose better habits this fall. Compounded medications are not FDA approved, eligibility required, and determined by a licensed provider. Individual results may vary. See website for details.

20:02This is an iHeart Podcast. Guaranteed Human.