Who Smarted? – What Causes the Northern Lights?

Podcast: Who Smarted?
Episode Date: December 29, 2025
Main Theme: Unraveling the science, mystery, and spectacle behind the Northern Lights.

Episode Overview

This episode of Who Smarted? takes listeners on a whimsical and fact-filled journey to Tromsø, Norway, where the host and his local friend Bjorn explain the real science behind the astonishing Northern Lights (Aurora Borealis). The show delivers engaging storytelling, trivia questions for “smarty pants” listeners, and plenty of laughs while teaching about solar wind, Earth’s magnetosphere, and the conditions that create dazzling auroral displays.

Key Discussion Points & Insights

1. Setting the Scene: Observing the Lights in Norway

• The host is in Tromsø with Bjorn, a local and self-proclaimed “northern lights expert.”
  • Quote [01:14]:
    Bjorn: “Oh, it just comes from being from the north of Norway. We get northern lights all the time.”

2. What Are the Northern Lights?

• Initial description: stunning, colorful, seemingly magical.
• Science vs. Magic:
  • Bjorn: “For starters, there's nothing magical about them, trusty. It's all science.” [02:45]

3. The Earth's Magnetosphere and Its Role

• Earth is surrounded by a magnetic field, the magnetosphere, originating from the core.
  • Bjorn explains the basics of magnetic fields and how they protect Earth from solar wind except at the poles. [03:37–04:44]
  • Quote [03:49]:
    Bjorn: “Earth has something called a magnetosphere. It’s basically the area surrounding the planet which is dominated by our magnetic field.”
• Northern lights occur primarily at the poles due to weaker magnetosphere shielding.

4. What Is Solar Wind?

• Solar wind: A stream of charged particles from the Sun, traveling about 1 million miles an hour.
  • Interactive Trivia [05:47]:
    • Host: “Smartypants, true or false. This solar wind, made up of charged particles from the sun, falls down to earth at about 1 million miles an hour. If you said true, you're right.”
• Interaction between solar wind and Earth's atmosphere (oxygen/nitrogen) creates the auroras.
  • Bjorn: “When the solar wind enters through those weak points in the atmosphere, it interacts with oxygen and nitrogen and boom, we get the northern lights.” [06:02]

5. Where and When Are the Northern Lights Visible?

• Places: Northern parts of Alaska, Canada, Greenland, Iceland, Scandinavia, and even upper Michigan and parts of Scotland.
• Time of Year: Mostly visible in the dark winter months, September to April, but technically occurring year-round.
  • Bjorn: “They're actually happening non stop 24/7 every single day of the year. ... But in order to see them, the conditions must be perfect.” [07:10–07:35]

6. What About the Southern Lights?

• Aurora Australis appears near the South Pole, in southern Australia, New Zealand, Argentina, Chile, and Antarctica.
  • Bjorn: “For some reason, the Southern lights aren't as famous as the northern lights. But they are exactly the same thing, just in a different location.” [08:12]

7. Why All the Different Colors?

• The color depends on the type of atmospheric gas and the altitude where the interaction occurs:
  • Oxygen (60–150 miles): Green
  • Oxygen (200+ miles): Red
  • Nitrogen (≤60 miles): Blue/Purple
  • Host recaps: “Blue and purple are the closest northern lights when reacting to nitrogen. Green lights mean close and reacting to oxygen, and red are the furthest away when reacting to oxygen.” [10:13–10:35]

8. The Fancy Names: Aurora Borealis and Aurora Australis

• Host quiz:
  “What do you think the Aurora Borealis means? ... It's actually B, northern dawn. The term was coined by the Italian astronomer Galileo Galilei.” [10:56–11:25]
• Aurora Australis = Southern dawn/lights

9. Auroras Further from the Poles: Extreme Solar Storms

• Rare solar storms can make auroras visible at unusual latitudes (e.g., London, Switzerland, Florida in May 2024).
  • Bjorn: “On rare occasions when solar storms are extra powerful, the lights can be seen further away. And that's exactly what happened in May of 2024.” [11:51–12:23]
• Scientists expect more chances in the near future.

10. Do Northern Lights Make Sounds?

• Sometimes, yes! Rarely, auroras generate a subtle sound in the right atmospheric conditions.
  • Bjorn: “After scientists studied the sounds in the north of Finland, they were able to prove they were indeed coming from the northern lights. ... But the sounds only occur if the static charge in the solar storm is especially powerful.” [13:27–14:05]
• Audio demonstration: a soft, eerie environmental sound.

11. Auroras on Other Planets

• Other planets have auroras too (if they have a magnetic field and atmosphere).
  • Bjorn: “Most of the other planets experience the northern lights as well. ... For the same reasons we do.” [14:51–14:56]
• Exception: Mercury, due to its closeness to the sun.
  • Host quiz: “Any guess which planet doesn't get any northern lights? ... If you said Mercury, you're right.” [15:22–15:34]

Notable Quotes & Memorable Moments

• Host, jokingly exaggerating the magic of the lights:
  “Nope. I'm in the city of Tromso in the far north of Norway, and I'm looking at the northern lights… No, not jellybeans or Skittles or Christmas lights.” [00:51]
• Bjorn, dryly summing up the science:
  “No magic. Pure science. Solar wind is a stream of charged particles that rain down from the atmosphere of the sun.” [05:38]
• Host, marveling at planets’ auroras:
  “Those other planets may have northern and southern lights, but they don't have anyone to look at them. So there.” [15:08]

Timestamps for Key Segments

| Timestamp | Segment Description | |-----------|------------------------------------------------------------| | 01:10 | Introduction to Bjorn, the local expert | | 02:45 | Science, not magic: Northern lights explained | | 03:37 | Role of Earth's magnetosphere | | 05:47 | “Solar wind” defined and explained | | 06:21 | Creating the auroras: Solar storms | | 07:10 | When and where to see northern lights | | 08:12 | The Southern Aurora explained | | 09:15 | Why the colors differ | | 10:56 | The meaning of Aurora Borealis | | 11:51 | Why auroras appear farther from the poles during storms | | 13:27 | Rare sounds of the northern lights | | 14:51 | Auroras on other planets | | 15:22 | Which planet can't have auroras? | | 16:05 | Close: “Maybe just a little bit magical.”/“Nope. Purely scientific.” |

Episode Tone & Style

• Friendly, enthusiastic, pun-filled: The hosts banter, quiz the audience, and make science fun with light sarcasm and nods to “magic” and “folklore.”
• Interactive: Trivia questions encourage listeners to participate.
• Conversational and playful: The hosts use recurring jokes and playful challenges to keep kids engaged.

Summary

Who Smarted? makes the science behind the Northern (and Southern) Lights exciting and accessible, covering Earth's magnetic field, solar wind, atmospheric chemistry, the colors’ origins, planet-level phenomena, and even the rare sounds auroras can produce. The episode also links learning to real-world events (solar storms of 2024) and gives listeners fun facts to spark curiosity, all wrapped in humor and interactive storytelling. This is a delightful and memorable introduction to one of nature's most magical-looking—yet thoroughly scientific—phenomena.