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The aurora shines above Coot Lake in Longmont, Colorado, in November 2025. (Credit: Ryan French)

Late on Friday, Nov. 7, Ryan French was flying from Denver to Chicago when he saw something surprising from his window seat: glowing green and purple lights in the skies high above the Midwest.

For French, a research scientist at the (LASP) at ÌÒÉ«ÊÓƵ, the event was a rare opportunity to witness the phenomena he studies. He’s a solar physicist who studies the sun’s volatile nature—dynamics that can, under certain circumstances, create brilliant light shows in Earth’s atmosphere. These phenomena are called the Aurora Borealis, or Northern Lights.

The scientist’s flight was a teaser for things to come: This week, people across the United States saw the aurora as far south as parts of Florida and Texas, and more displays may be in store in the nights to come.

French writes about these events for non-specialist audiences, and his book is coming out in December.

He gives his take on what causes this kind of phenomenal light show, and provides tips for how Coloradans might catch these lights in the sky.

Ryan French speaks in front of an image of the surface of the sun at the Fiske Planetarium at ÌÒÉ«ÊÓƵ. (Credit: Ryan French)

French and his wife gaze at the aurora in Colorado in November 2025. (Credit: Ryan French)

The aurora above Coot Lake in November 2025. (Credit: Ryan French)

What causes the aurora?

Essentially, you have an eruption of stuff from the sun. This is called a coronal mass ejection. It’s an ejection of mass from the sun’s corona, which is the word we use for the sun’s atmosphere.

It can take several days for the coronal mass ejection to reach Earth, but when it does, it slams into Earth's magnetic field and high energy particles will enter our magnetic field. They will then slide down towards the North and South Poles, and those particles will collide with the air in our atmosphere and cause the atmosphere to glow.

The different colors you see in the aurora are caused by different elements at different heights being smacked by these high energy particles from space.

This isn’t the first time we’ve seen the aurora this far south in recent years—there was a major solar storm in May 2024. Why is that?

The sun follows an 11-year cycle of increasing and decreasing solar activity. We call this the solar cycle. At the peak of this cycle, where we are now, there are lots of sunspots on the sun. These produce a lot of solar flares and eruptions that head towards Earth.

At the bottom of this cycle, the sun doesn't really do anything for years at a time. After the next year or two, we're going to have an absence of major events on the sun for a few years.

Can these events pose a danger to humans?

The largest events from the sun can disrupt things like power grids and satellite navigation. But this week’s event was not strong enough that anyone at home needs to be concerned. But, if you work in satellite operations, you will be taking extra steps to the monitor the positioning of your spacecraft.

How are scientists trying to reduce those risks?

We are observing the sun 24 hours a day, seven days a week. If there is a solar flare or an eruption from the sun, there are alerts that are sent out. Industries will look at these forecasts and take necessary actions to try and minimize the risks.

How can people see the aurora?

During active periods of the aurora, my advice is to head out, face north and get away from streetlights. Maybe you'll be able to see some greens and reds with your eye. But if you can't, just take out your phone, set a long exposure, take the photograph, and you'll see those colors beginning to pop.

Why are phones better at seeing the aurora than human eyes?

The human eye is not great at seeing in the dark. When your eyes adjust at nighttime, your color perception isn't fantastic, but a camera will pick up those colors that your eye cannot.

Why do you like seeing the aurora so much?

I am a solar astrophysicist, so I research the sun and the origins of these events. To see firsthand the influence of something 93 million miles away happening above our heads is quite striking. The aurora sends the message that Earth is not just an isolated bubble in space, but we live in a solar system. We live next to a star.

I've seen the aurora many times now, and every time it's different. The colors, the shapes, they all vary from time to time.