The Cassini Mission to Saturn

pia03883-nohuygensThe Cassini mission to Saturn launched 20 years ago, on October 15, 1997.  It took seven years to reach Saturn, and has been orbiting and intensely studying Saturn ever since…until last week when the mission ended in a final dive into Saturn’s atmosphere.  The mission studied Saturn, its famous rings, and its many moons using a suite of instruments that observed a broad range of wavelengths from ultraviolet, to visible, infrared, and radio as well as examining dust, charged particles, and magnetic fields.  It also delivered the Huygens probe that descended through the atmosphere of Saturn’s giant moon, Titan.

In this edition of How on earth, we have two scientists from the Cassini mission team.  Dr. Larry Esposito is a Professor at the Astrophysical and Planetary Sciences department at the University of Colorado at Boulder and member of the Laboratory for Atmospheric and Space Physics at CU.  Dr. Carly Howett is a planetary scientist and manager at the Southwest Research Institute in Boulder.  They share with us some of the science from Cassini-Huygens and experiences working on such a long-term and successful space mission.

Host / Producer / Engineer: Joel Parker
Additional Contributions: Beth Bennett, Shelley Schlender
Executive Producer: Alejandro Soto

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Biofuels Tradeoffs

corn-field-farm-vertical-PA
Biofuels Tradeoffs (start time: 8:27): In this week’s show David DeGennaro, an agriculture policy specialist with the National Wildlife Federation and author of a report called “Fueling Destruction,”  talks with host Susan Moran about the environmental consequences of biofuels, and about possible solutions. The Environmental Protection Agency has proposed maintaining record support for biofuels, namely corn. Last week the EPA ended an open public comment period leading up to a decision to maintain, increase or scale back its current support of biofuels as part of the Renewable Fuels Standard, a federal mandate to blend corn-based ethanol and other renewable fuels into conventional gasoline. NWF and some other environmental organizations, along with former California Congressman Henry Waxman, have been urging the EPA and Congress to reduce biofuels mandates. Increased demand for corn has led to the conversion of millions of acres of habitat-rich grasslands and into croplands — all without significantly reducing greenhouse gas emissions.

Hosts: Susan Moran, Joel Parker
Producer: Susan Moran
Engineer: Joel Parker
Executive Producer: Alejandro Soto
Additional contributions: Alejandro Soto

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Climate Change and Extinctions Following an Asteroid Impact

asteroid_impactClimate Change and Extinctions Following an Asteroid Impact (starts at 8:45) It has been hypothesized that the dinosaurs were killed off by a large asteroid that struck the Earth. The details of how the impact of a 10 kilometer diameter asteroid led to global scale extinction have remained elusive. Recently, climate researchers from the Boulder area published new climate model results that show how the asteroid impact ultimately leads to widespread cooling in the atmosphere and increased exposure to ultraviolet radiation. These drastic and rapid changes to the climate due to the asteroid impact may explain the global scale extinction.

Two of the authors join us today to talk about this new research. Dr. Charles Bardeen works as a scientist at the National Center for Atmospheric Research, and is the lead author of the new paper. Joining Dr. Bardeen is Professor Brian Toon, a co-author of the new research and a professor at the University of Colorado, Boulder.

Hosts: Alejandro Soto & Joel Parker
Producer and Engineer: Joel Parker
Additional Contributions: Susan Moran, Beth Bennett, Chip Grandits
Executive Producer: Alejandro Soto

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Stay Young – If You’re a Worm

Age

Age

This week on How on Earth, Beth spoke with Dr Gordon Lithgow, a researcher at the Buck Institute for Aging in California who studies aging in nematode worms. Stress actually keeps us young by activating systems that repair and maintain cells. These stresses can be things like caloric restriction and exercise. Eventually the molecular bases of these stresses will be identified and may lead to interventions to slow aging.

Hosts: Beth Bennett & Joel Parker
Producer: Beth Bennett
Engineer: Joel Parker
Additional Contributions: Beth Bennett
Executive Producer: Alejandro Soto

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Mortality Trends in America // Life Expectancy in America

This week on How on Earth we look at the scientific research into the lifespans of Americans.

Andrea Tilstra

Andrea Tilstra

Mortality trends in America (start time 4:05): We speak with Andrea Tilstra, who co-authored a recent paper on mortality trends in America. Tilstra is a co-author of a recent study published in the International Journal of Epidemiology.  Her team’s paper is titled “Explaining recent mortality trends among younger and middle-aged White Americans.” 

 

 

S. Jay Olshansky, Ph.D., of the School of Public Health at the University of Illinois at Chicago. Photo by Kevin J. Miyazaki/Redux

S. Jay Olshansky, Ph.D.

Life expectancy in America (start time 12:40): Next, we speak with Jay Olshansky, who ten years ago first predicted the recently observed drop in life expectancy in America. Olshansky is a world renowned expert in the Science of Aging.  As for his crystal ball – well, it has little to do with magic, and more to do with his understanding about how our cells work, and how they age.  It also helps that he understands statistics.

 

Hosts: Alejandro Soto, Joel Parker, Shelley Schlender
Additional Contributions: Beth Bennett
Producer: Alejandro Soto
Engineer: Joel Parker
Executive Producer: Alejandro Soto

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Chasing Shadows – Stellar Occultations and the Outer Solar System

Shadow Chasers (Photo: Jack Jewell)

Shadow Chasers
(Photo: Jack Jewell)

Chasing Shadows [starts at 9:40]  Astronomy is a science that depends on watching things happen in the universe that we don’t have control over: supernovae, formation of stars, orbits of planets, and the spectacle of solar eclipses.  You can’t grab a distant galaxy and bring it into the lab for experiments, so astronomers have to depend on studying the light that fortuitously comes to them from distant objects.  However, by studying just that light, we can learn much about the objects in the universe and how they formed and evolved.  For example, studying solar eclipses have taught us about the corona of the sun and about general relativity.   To make those observations and measurements, scientists have to chase the shadow and set up their laboratory in remote places to catch it.  In this edition of How on Earth we talk with one such shadow-chaser: astronomer Dr. Marc Buie from the Boulder office of the Southwest Research Institute.  Marc organized a set of expeditions around the Earth to observe occultations of the Kuiper belt object 2014 MU69, which is is the next flyby target of the New Horizons space mission that flew past Pluto in July 2015.  He explains the science of occultations, what can be gleaned from these shadowy observations of 2014 MU69, and talks about planning for observation expeditions to remote places around the world.

Hosts: Joel Parker, Chip Grandits
Producer / Engineer: Joel Parker
Executive Producer: Alejandro Soto

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The Alien Hunter & SETI

Contact cover-lrgToday’s show offers the following feature:
Extraterrestrial intelligence? (start time: 6:30): It’s mid-summer, a time when many of us like to spend leisurely time outside at night, gazing at the stars and planets, and asking the big existential questions, such as, Are we alone? Is there intelligent life waaay out there? Our guest today, science writer Sarah Scoles, has pondered these questions for several years. She discusses with hosts Susan Moran and Joel Parker her just-published biography, Making Contact: Jill Tarter and the Search for Extraterrestrial Intelligence. Tarter, an astronomer, directed the Center for SETI (Search for Extraterrestrial Intelligence) Research. Carl Sagan’s 1985 novel Contact” illustrates Tarter’s astronomical work. In the 1997 movie Contact (stemming from Sagan’s novel) actor Jodi Foster played a character  who was loosely based on Tarter.

Hosts: Susan Moran, Joel Parker
Producer: Susan Moran
Engineer: Joel Parker
Executive Producer: Alejandro Soto

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Is Your Oral Microbiome Affected by Your Genes?

Twins face to face

Twins face to face

On the first day of the summer pledge drive, Beth interviews Dr Brittany Demmitt, a behavioral molecular geneticist. Her recent study used a powerful genetic tool, identical twins, to show that the micro biome in the mouth is influenced by both genes and environment.

Hosts:Beth Bennett, Chip Grantis, Joel Parker
Producer:Beth Bennett
Engineer:Joel Parker
Additional Contributions:Beth Bennett
Executive Producer:Alejandro Soto

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The American Eclipse of 1878

Cover-300-wideThis August 21st, some parts of the Earth will be plunged into darkness in the middle of the day.  It will be a solar eclipse; the moon’s shadow will cross the United States from Oregon to South Carolina, with the path closest to Colorado passing through Wyoming and Nebraska.

There have been many eclipses across the US, but there was a particularly special one nearly 140 years ago on July 29th, 1878.  That eclipse came at a time in American history of western expansion, industrial growth, new inventions and World’s Fairs, and a young country wanting to establish itself on the international stage of science and technology.

Our guest today is David Baron, author of a book about that eclipse.  The book is “American Eclipse: A Nation’s Epic Race to Catch the Shadow of the Moon and Win the Glory of the World”.  David joins us to talk about that eclipse, the people involved in observing it, and its part in Colorado history.

Hosts: Joel Parker, Susan Moran
Producer / Engineer : Joel Parker
Executive Producer: Susan Moran

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2017 Graduation Special (part 2)

diploma-and-graduation-hatWith graduation season is upon us, or in many cases in the rearview mirror, today’s edition of How on Earth is the second of a two-part “Graduation Special”. Our guests in the studio today are scientists who recently graduated with – or soon will receive – their Ph.D.  They talk about their thesis research, their grad school experiences, and what they have planned next.

abbyAbby Koss – CU Boulder, Chemistry and Biochemistry
Topic: New Insights into Fossil Fuel Volatile Organic Compound Emissions and Chemistry using H3O+ and NO+ Chemical Ionization Mass Spectrometry

 
matteoMatteo Crismani – CU Boulder, Department of Astrophysical and Planetary Sciences
Topic: Cometary Gas and Dust Delivered to Mars

 

Version 2Callie Fiedler – CU Boulder, Electrical Engineering
Topic: Characterizing the Properties of 3D Printed Hydrogels for Regenerative Medicine

 

 

Host / Producer / Engineer : Joel Parker
Executive Producer: Susan Moran

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