
KGNU - How On Earth
The KGNU Science Show
Latest episodes

May 12, 2025 • 45min
GoldLab Founder Larry Gold – Extended Interview
This is Shelley Schlender’s extended interview of Larry Gold, founder of the GoldLab Symposium. For the broadcast version, go here.
Producer: Shelley Schlender
Larry Gold

May 6, 2025 • 29min
2025 Graduation Special (part 1)
With graduation season upon us, today’s edition of How on Earth is Part 1 of our annual “Graduation Special”. Our guests in the studio today are scientists and engineers who have or will soon receive their Masters or Ph.D. from the University of Colorado in a STEM-related field. They talk about their thesis research, their grad school experiences, and what they have planned next.
Renee Spear – Aerospace Engineering
Topic: Collision-Free Spacecraft Trajectory Design in Multi-Body Systems
Gautam Kavuri – Physics
Topic: Wringing the Bell: Implementations of Cryptographic Protocols Based on Bell Non-locality
Dhyey Bhavsar – Aerospace Engineering
Topic: Shape Diameter Computation on Surface Meshes and A Review of Shape Regularization Methods in Level-Set Topology Optimization
You can listen to all past year Graduation Special episodes.
Host / Producer: Joel Parker
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Apr 29, 2025 • 27min
Mutualism in Nature
Sweet in Tooth and Claw (start time: 0:59) Since the 1800s, science has been obsessed with the notion, stemming from Charles Darwin’s theory of evolution through natural selection, that only the “fittest” can survive and pass on their strong genes. As in, it’s a ruthless, violent world. And today, we humans find ourselves mired in a hyper-polarized society fixated on competition, disruption, and “If you win, I lose” thinking. A good time to take a look at a different way of living together–how a “kinder, gentler” approach also helps species evolve. In this week’s show, Susan Moran interviews journalist/author Kristin Ohlson, whose most recent book, Sweet in Tooth and Claw: Stories of Generosity and Cooperation in the Natural World, was recently released in paperback by Patagonia Works.
Host/Producer: Susan Moran
Engineer: Jackie Sedley
Executive Producer: Joel Parker
Listen to the show here:

Apr 22, 2025 • 27min
De-funding NIST’s Atomic Spectroscopy Group
Alexander Kramida – NIST Atomic Spectroscopy Group – phote from NIST
Federal cutbacks have led the National Institute of Standards and Technology to shut down a long-running, highly prized information center used by scientists around the world, for projects ranging from searching for exoplanets, to making better microchips, to detecting atomic missiles. Atomic Spectroscopy Database Manager Alexander Kramida explains the purpose of the Atomic Spectroscopy Group, the impact of losing it, and what’s next, now that federal budget cuts mean NIST is shutting it down.
For a Transcript, go here.
Host & Show Producer: Shelley Schlender
Additional Contributions: Joel Parker
Executive Producer: Joel Parker

Apr 15, 2025 • 27min
The Lucy Mission
image credit: NASA
Our guest today is Dr. Simone Marchi, Institute Scientist in the Solar System Science & Exploration Division at the Boulder office of Southwest Research Institute. Dr. Marchi is the Deputy Principal Investigator for NASA’s Lucy mission. Lucy will be the first space mission to explore a population of small bodies known as the Trojan asteroids, which orbit out at the distance of Jupiter. Lucy has two “practice” flybys of main belt asteroids: Dinkinesh in November 2023, and Donaldjohanson coming up in just a few days on April 20, 2025.
Producer and Host: Joel Parker
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Apr 8, 2025 • 27min
Poisoning the Well: How Forever Chemicals Contaminated America.
Poisoning the Well (starts 2:00) Boulder science writer Sharon Udasin discusses her new book, Poisoning the Well: How Forever Chemicals Contaminated America. The book chronicles how these chemicals have ended up in our soil , drinking water, our bloodstreams . . . including in Colorado. She also explains what we can do about these sometimes useful, but far too often, health-endangering chemicals.
Sharon will speak April 8th at the Boulder Bookstore.
Other events discussed in this show are the CU-Boulder Conference on World Affairs and the Dinosaur Ridge Raptorthon
Special thanks to Simon Roberts and his youtube channel, Environmental Chemistry Explained, for the song, “Forever Chemicals.”
Producer and Host: Shelley Schlender
Executive Producer: Joel Parker
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Apr 1, 2025 • 27min
April Foolish Science
Today is April Fools’ day, when jokes and pranks are played, sometimes among friends and family, sometimes on a more public scale. But why is there such a day for culturally-accepted foolishness? To delve into the origins and history of April Fools’ Day, we talk with Dr. Angus Kress Gillespie, folklorist and professor of American studies at Rutgers University.
(Image credit: Zurijeta | Shutterstock.com)
You might find it shocking that scientists have a sense of humor, so we also talk with, Dr. Mike Lund from the NASA Exoplanet Science Institute at the Infrared Processing & Analysis Center / CalTech about the tradition among Astronomers to write and even review humorous research papers for April Fools’ day. These papers are often posted on the arXiv preprint server, and Dr. Lund, the author of several such papers, also is the editor of the Acta Prima Aprilia that shares some of those papers.
Producer and Host: Joel Parker
Additional contributions: Beth Bennett
Executive Producer: Joel Parker
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Mar 25, 2025 • 26min
NEPA, Wildlife, Lands Under Threat
oil and gas rig Image courtesy of USGS
NEPA rollbacks, environmental impacts (start time: 6:25) Amidst a flurry of moves by the Trump administration to roll back environmental regulations, last month a White House agency proposed a rule to rescind a landmark law meant to protect wildlife, their habitat, and human communities from unchecked development, and to ensure that the public has a say in projects ranging from oil and gas drilling to wind and solar farms. The rule, if it goes into effect, would mean that the White House Council on Environmental Quality would no longer enforce how the National Environmental Policy Act (NEPA) is carried out. As a result, many infrastructure projects would not be subject to environmental review. A public comment period regarding this proposed rule ends on Friday, March 27. (Click here to submit any comments.) How On Earth host Susan Moran interviews Jim McElfish, a senior advisor at the Environmental Law Institute, a nonpartisan, nonprofit center working to strengthening environmental protection by improving law and governance.
Hosts: Susan Moran, Joel Parker
Show Producer: Susan Moran
Engineer: Joel Parker
Headline contributors: Beth Bennett, Joel Parker
Executive Producer: Beth Bennett
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Mar 17, 2025 • 27min
Measles: To Vaccinate or Not?
In this discussion, Brianne Barker, an Associate Professor of Biology and Director of Undergraduate Research at Drew University, shares her expertise on the measles virus. She explains how measles invades cells and wreaks havoc on the immune system, causing long-term health issues. The conversation emphasizes vaccine importance in preventing immune amnesia, where the virus erases memory of past infections. Barker also unpacks the virus's complex life cycle and its ability to outsmart immune defenses, highlighting urgent public health implications.

Mar 11, 2025 • 26min
This Ordinary Stardust: A Scientist’s Path from Grief to Wonder
We speak with Environmental Scientist Alan Townsend about his new book, This Ordinary Stardust: A Scientist’s Path from Grief to Wonder. It chronicles what happened when his family received two unthinkable, catastrophic diagnoses: his 4-year-old daughter and his brilliant scientist wife developed unrelated, life-threatening forms of brain cancer. As he witnessed his young daughter fight during the courageous final months of her mother’s life, Townsend – a lifelong scientist – was indelibly altered.
Executive Producer: Beth Bennett
Show Producer: Shelley Schlender
Hosts: Joel Parker and Shelley Schlender
Engineer: Joel Parker
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