The sun may seem like it's stable, stagnant, not much really going on there, but if we take a closer look, we can see that the sun is very much alive, bubbling, burping and sneezing energy all over the place constantly. But this year that burping and sneezing seem to be more powerful and happening more frequently, some of that energy even coming towards Earth. So what's happening? What's going on with our sun? Grab those hats and sunglasses, because we are about to learn about the solar cycle.

[uptempo electronic music]

(Describer) In shiny blue and purple letters, title: The Space Gal. Underneath: www dot TheSpaceGal dot com.

Hi everyone, I'm Emily Calandrelli, your friendly neighborhood Space Gal, and welcome to my channel where we talk about all things space and science. You may have heard that the sun is particularly active right now with X-class solar flares coming our way. You may have even heard that you could see an aurora in your area, but what does this mean? Why is this happening? And should you be afraid? Well, first, it is perfectly natural for our sun to be active. After all, our sun is a nuclear fusion reactor constantly turning hydrogen into helium via fusion. I often hear people ask if there's no oxygen in space, how does the sun burn? Easy; the sun doesn't need oxygen. It's not burning like a campfire, it's radiating like a nuclear bomb. The nuclear fusion that's happening inside the sun doesn't require oxygen, but this does create a ton of energy, or thermal radiation, which is why the sun glows. And through all of this, the sun has plasma swirling across the surface and chaotic magnetic fields that dance and move. And the coolest part about all of this is that the sun goes through cycles. It waxes and it wanes, it has periods where it's more active with more burps and sneezes of energy and periods where it's less active. This up and down cycle is on average about 11 years long, but it can be as short as eight years, or as long as 14. We are currently in Solar Cycle number 25 and approaching the maximum within that cycle in the year, 2025. There have of course been countless solar cycles, but we only began extensive recording of these cycles in 1755, which kicked off what scientists call Solar Cycle number one. During one solar cycle, we see a solar minimum with low solar activity, and a solar maximum with high solar activity. Solar activity can be measured with the number of sunspots. Sunspots are the markers where powerful magnetic fields have emerged from the sun. Those magnetic fields power things like solar flares and coronal mass injections. Solar Cycle number 25 began in December, 2019 with a solar minimum and is expected to reach its solar maximum in the year, 2025. And because we are approaching a solar maximum you can expect to see more news about something called X-class solar flares. Solar flares are big explosions on the sun that occur when energy stored and twisted magnetic fields is suddenly released. There are five classes of solar flares, A, B, and C and M, which stands for medium, and then finally X-class, the most powerful of all. Each class is 10 times more powerful than the one below it, which means that X-class solar flares are just gargantuan compared to AB, or even C ones, which are just too weak to affect the Earth. In fact, X-class solar flares are the largest explosions we see in our solar system. Some of the larger X-class solar flares have had the energy of 10 billion hydrogen bombs. Good thing we are located 94 million miles away, but X-class solar flares aren't rare. We see about a handful a year, and more than a dozen a year during solar maximum. But X-class solar flares, particularly the more powerful X-class solar flares, can generate geomagnetic storms that can hurt our satellites in space, or even our ground-based power systems. They frequently create temporary radio blackouts, and can even cause auroras in areas that don't normally see them, but these solar flares and geomagnetic storms are not physically dangerous to humans. You see, the largest geomagnetic storm in history was the Carrington Event of 1859. It occurred during the solar maximum of Solar Cycle 10, and is estimated to have been an X45 class solar flare, meaning it was 45 times more powerful than an X1 class solar flare. Astronomer, Richard Carrington, saw bright flashes on the surface of the sun from his observatory in London. What he witnessed was a once-in-500-years event, an enormous X45 class solar flare. Hours later, the effects were seen all around the world. Auroras illuminated the skies, so much so that people thought the sun was rising in the middle of the night. The geomagnetic storm increased the electrical current flowing through telegraph communication wires causing many of those systems to fail. There were even some reports of telegraph operators getting shocked or sparks caused by the enhanced electrical current, creating fires. It was a big deal back then. But today we rely even more on technology. So the question remains what would happen if we experienced a Carrington-level event today? Large geomagnetic storms make our upper atmosphere denser increasing the drag on low orbiting satellites, making them deorbit sooner. The increased radiation from these storms can also damage satellites although some satellites are now equipped with radiation-hardened or rad-hard electronics to help protect them from this. And finally, power grid systems on the ground can be damaged just like they were during the Carrington event. So in short, a Carrington level event today could potentially completely disrupt our entire technological world temporarily. It could damage satellites that we rely on for GPS, communications, and national security, and it could temporarily cause blackouts across power grids for a few weeks. This is precisely why it's important for scientists to monitor, study, and model our sun, so that we can warn communities when this type of event is happening, and possibly even be able to predict these events before they happen in the future. To summarize, expect to see more reports of X-class solar flares as we build up to these solar maximum in 2025. They'll likely cause radio blackouts here and there, and you might hear reports of auroras in locations that you don't normally see them, but they're not likely to be Carrington-level events. Hopefully that puts your mind a little bit at ease, but stay tuned, I'll be sure to report back if that changes. Thanks for joining me today. Stay tuned for many more videos on science and space. And as always, stay curious and keep exploring. We'll see you next time.

(Describer) In shiny blue and purple letters, title: The Space Gal. www dot TheSpaceGal dot com. In outtakes, she tries to put on a pink NASA cap and sunglasses.

[uptempo electronic music]

Wrap those hats and... Grab those hats [laughs]. Grab those [laughs]. See you next time. Grab those hats and sunglasses!

(Describer) Against a white background, plumes of blue and purple smoke shoot out at each other and dissipate to reveal the Space Gal logo. Titles: Thanks for watching! Don’t forget to like, subscribe and share. Accessibility provided by the US Department of Education.

[uptempo electronic music]

Accessibility provided by the U.S. Department of Education.

[logo whooshing]

[mouse clicking]

[bell dinging]