Broadcast 3417 Dr. Kirby Runyon

The Space Foundation Conference

22 Nov 2019 Dr. Kirby Runyon
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Guest:  Dr. Kirby Runyon;  Topics:  Planetary nomenclature, taxonomy, the IAU and Pluto, the NASA-APL Interstellar Probe Concept Mission and much more.

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We welcomed to the show Dr. Kirby Runyon of APL to discuss two main topics, planet nomenclature and taxonomy then later the proposed NASA-APL Interstellar Probe Concept Mission.  We started this one segment 66 minute discussion with our guest introducing us to the topic of planetary nomenclature and the overall subject of taxonomy, the science of naming things, in this case, planets.  Our guest talked about planet history and the IAU Pluto controversy and why it was so important, especially for teaching science and in text books.  Dr. Runyon talked about why the IAU was not even qualified to hold a vote let alone thinking that science was based on democracy. This was a detailed discussion on the topic with multiple listener email questions.  In addition, our guest introduced us to the geophysical planet definition so don't miss it.  Part of our discussion zeroed in on the fact that planets were and are defined by intrinsic properties, not where they are or what they orbit.  Don't miss what our guest had to say about planet shape, why they are typically round plus the role gravity plays with planets. 

Exoplanets were brought into the discussion and as you will hear, were and are an important part of planet identity.  We talked about the first exoplanet discovery and the field through the current time.  Dwarf planets were another major part of our discussion as were the surprising number of planets our guest mentioned in the solar system.  If you think nine, guess again.  Later near the end of the planet part of our discussion, listen to what Kirby said about a Planet 9 and also Planet 5. 

After spending about 75% of our program time on planetary nomenclature issues, we turned to the concept mission, the NASA-APL Interstellar Probe.  Check out the website for the proposed concept mission here:  After describing what a NASA Concept mission was, Kirby went into detail about this mission, its capabilities, technical specs, flying beyond the heliosphere, speeds, distances measured in AU and what that means, possible study targets beyond the heliosphere, travel times, even a comparison with the proposed Breakthrough Starshot project.  This concept mission would eventually need to be selected as part of the Decadal Survey in order to become a NASA mission so the verdict is out on it at this time.  Don't miss what our guest said when I asked if there was something interested people could do to help the mission get accepted as a real mission. Near the end of the discussion, I asked about mission costs which he said might be between $1-4 billion.

Please post your comments/questions about this program on our blog.  You can reach Dr. Runyon through me or his APL and NASA information pages. 




planetary definition, dwarf planets interstellar, lot's more

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