Why is star formation the workhorse of the universe? What is a flocculent galaxy? Which cosmic cataclysm creates new globular star clusters? And why are we currently seeing such amazing aurora in unusual places?
To find out, Dr. Charles Liu and co-host Allen Liu welcome astronomer Dr. Kelsey Johnson, past president of the American Astronomical Society (AAS) and of the Astronomical Society of the Pacific (ASP), and author of “Into the Unknown – The Quest to Understand the Mysteries of the Cosmos.”
As always, though, we start off with the day’s joyfully cool cosmic thing, the auroras that have been occurring during the peak of the current solar max period of the roughly 11-year-long solar cycle. From the Mother’s Day aurora borealis in May to the amazing night of October 10, when millions of people as far south as Florida and Mexico were treated to one of the most spectacular, vibrant light shows many of them had ever seen.
Kelsey shares the story of the first time she saw an aurora, as a high school student in Minnesota who didn’t even know what one was. Upon leaving her boyfriend’s house at around 2 in the morning, she saw a brilliantly glowing sky. Kelsey’s availability bias kicked in, and her assumption was that it had to be either god or aliens, with the latter being the more likely. Needless to say, the next day the front page of the local paper solved the mystery.
And then it’s on to a nerdy discussion of existential curiosity, deep, philosophical questions, and her book, “Into the Unknown.” You’ll hear what drove Kelsey to write the book, and about her lifelong drive to understand our place in the universe. Kelsey and Allen nerd out over Calabi-Yau manifolds (concepts from string theory), imaginary numbers and complex numbers, Euler’s Formula and more, and then, thankfully, it’s time for our first question.
Johnny asks, “What is a flocculent galaxy, and why are they interesting?” Kelsey says that they’re spiral galaxies with spiral arms that aren’t very pronounced, that are exceptionally “floofy and chaotic” with very different, but very cool star formation. Chuck and Kelsey explain why star formation is the workhorse of the universe and how important it is. Kelsey also explains why globular clusters are her “favorite” type of star cluster. There are about 150 of them living around our galaxy, and they’re almost as old as the universe itself, over 10 billion years old. Kesley studies them to learn how the universe was formed and how galaxies came together. New globular clusters are rare, but they can be created by the collision of two galaxies.
That’s all we could squeeze into Part 1, but come back in two weeks for Part 2 of "Into the Unknown with Dr. Kelsey Johnson."
If you’d like to know more about Kelsey, you can visit her website at and follow her on Twitter (X) and Instagram at @ProfKelsey,
We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.
Credits for Images Used in this Episode:
- Graph of the solar cycle – David Hathaway, NASA, Marshall Space Flight Center, Public Domain
May 2024 aurora in Northern Ireland – David Kernan, CC BY
May 2024 Aurora from Chihuahua, Mexico – Levi bernardo, CC BY
Chuck & Allen’s view of the October 2024 aurora – Allen Liu
Eugenio Calabi and Shing-Tung Yau – National Science Foundation, Public Domain
Eugenio Calabi and Shing-Tung Yau – Konrad Jacobs
3D model of a Möbius Strip – Inductiveload, Public Domain
3D model of a Klein bottle – Lukáš Hozda, Public Domain
Number line – Rumil, Public Domain
Complex Plane – Brigban, Public Domain
NGC 2775, a flocculent galaxy – European Space Agency, CC BY
Messier 2, a globular cluster – NASA Hubble, CC BY
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