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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Pluto Flyby // Case of the Rickety Cossack

PlutoPluto Flyby  (start time 1:00): Joel Parker discusses the New Horizons mission from the command center live!

Case of the Rickety Cossack (start time 25:00): Beth Bennett talks to Ian Tattersall about his new book,  a fascinating précis of the study of human evolution and some startling new findings showing that our species is one of many hominids in which natural selection mixed and matched various characteristics and abilities.

Host: Beth Bennett
Show Producer: Beth Bennett
Board Engineer: Maeve Conran
Executive Producer: Susan Moran
Additional Contributions: Susan Moran

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Distributed Energy // Pluto’s Occultation

In today’s How On Earth we have two features:
Distributed Energy (start time 5:46): Enjoying the twinkling stars without nighttime light pollution is a luxury for many of us. We can flick on the switch when we return home, after all. But think what would it be like if you were among the 1.5 billion people around the world who lack to centralized electricity. Having no lights at night keeps many of them  poor and illiterate, and it can create a public health and national security crisis. How On Earth co-host Susan Moran interviews two experts in the field of distributed and decentralized energy.  Rachel Kleinfeld is co-author (along with Drew Sloan) of a new book called Let There Be Light: Electrifying the Developing World with Markets and Distributed Energy.” She is CEO of the Truman National Security Project. Stephen Katsaros is  founder of Nokero, a Denver-based startup company that makes solar LED light bulbs.

Marc Buie of SWRI in Chile, photo courtesy of Sky and Telescope

Pluto’s Occultation (start time 16:31): It is a good time these days for watching solar system. Last week there was a solar eclipse, next week is a lunar eclipse and a transit of Venus (where Venus can be seen moving across the disk of the Sun).  Next week there is yet another solar system event of one object moving in front of another, though it’s not visible without the aid of a telescope. On June 4th Pluto will pass in front of a relatively bright star, an “occultation” event that will send teams of astronomers scrambling around the world to observe.  One team member is How on Earth’s own Joel Parker, an astrophysicist with the Boulder office of the Southwest Research Institute. He’ll be deployed to an observatory in New Zealand to observe the occultation.  Joel talks with How On Earth co-host Tom McKinnon on the eve of his adventure about the occultation and why scientists are interested in observing it. (Here’s an article and video about last year’s occulting Pluto.

Hosts: Tom McKinnon, Susan Moran
Engineer: Jim Pullen
Producer: Susan Moran
Executive Producer: Joel Parker

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Pluto’s Moons // Wildlife Preservation

(credit: NASA, ESA, M. Showalter, Z. Levay)”]Pluto and its moons [click to enlarge] (credit: NASA, ESA, M. Showalter, Z. Levay)Feature #1:
Last month, astronomers working on the Hubble Space Telescope announced the discovery of another, fourth moon around Pluto; this moon is so small that it could fit easily inside Boulder County (a pretty tricky thing to find at a distance of three and a half billion miles). The researchers who found the new moon were making observations in support of NASA’s New Horizons spacecraft, which is en route to fly by and study Pluto in 2015, and continue onward to explore the mysterious region beyond Pluto’s orbit known as the Kuiper Belt. How On Earth’s Ted Burnham recently met with Alan Stern, principal investigator on New Horizons, to talk about what the discovery means for that mission. [An extended version of the interview also is available.]

Harvey Locke  in Jasper National Park, Canada.  Jasper is part of the Yellowstone to Yukon corridor (Photo credit: Marie-eve Marchand)

Harvey Locke in Jasper National Park, Canada. Jasper is part of the Yellowstone to Yukon corridor (Photo credit: Marie-eve Marchand)

Feature #2:
The significant loss of species on Earth is primarily due to human destruction of habitats, forests and other wild nature, to make room for new development and agriculture. Climate change is also accelerating the rate of species extinction. Among the efforts worldwide to protect wilderness and nature so wild animals can survive is a Boulder-based nonprofit called The WILD Foundation. Harvey Locke is the organization’s vice president for conservation strategy and he helped launch the Yellowstone to Yukon Conservation Initiative (Y2Y) several years ago and oversees a global campaign called Nature Needs Half. Y2Y’s goal is to create a continuous 2,000-mile corridor for wildlife from Yellowstone National Park in the U.S. to the Yukon in Northern Canada. Harvey joins us in the studio to talk about that campaign and the science behind wildlife preservation targets.

Co-hosts: Susan Moran and Joel Parker
Engineer: Joel Parker
Executive Producer: Susan Moran
Show Producer: Joel Parker

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Extended interview with Alan Stern

On today’s show we featured an interview with Alan Stern of the Southwest Research Institute, who is principal investigator on NASA’s New Horizons mission. He told us about a fourth, tiny moon orbiting Pluto—found last month by his team during observations in support of New Horizons, which will arrive at Pluto in 2015. Here’s an extended version of that interview.

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