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NASA’s New Planetary Defense Office

Artist's concept of near-Earth asteroids

Air Date: 02/02/2016
Run Time: 50:35

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  • Lindley Johnson, Planetary Defense Officer, NASA
  • Kelly Fast, Astronomer and Manager of the Near Earth Object Observation Program, NASA

Topics: Voyager 1 and 2, Pioneer 10 and 11, Dawn, asteroid 1 Ceres, near-Earth asteroids, Mars Odyssey, Earth impact hazard, asteroids, Planetary Radio, Earth, International Space Station, Mars, Bill Nye

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Lindley Johnson has just been named NASA's first Planetary Defense Officer. He's joined on this week's PlanRad by astronomer Kelly Fast, the new manager of the Near Earth Object Observation Program. Emily Lakdawalla presents her “What’s Up in the Solar System” mission review for February. Bill Nye has birthday greetings for Voyager’s Ed Stone. Bruce and Mat learn that finding your way across the galaxy with pulsars can be very entertaining.

Planet 9

Caltech / R. Hurt (IPAC)

Planet 9
Artistic rendering of Planet 9 with the distant Sun in the background.

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Trivia Contest

This week's prizes are a lovely Planetary Radio t-shirt, a 200-point astronomy account AND a set of Year In Space wall and desk calendars.

This week's question:

In Earth days, how long is a Pluto day (as well as a Charon day)?

To submit your answer:

Complete the contest entry form at or write to us at no later than Tuesday, February 9th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

Where in the solar system is Anthony Patera?


The answer will be revealed next week.

Question from the week before:

On plaques carried by the Pioneer 10 and 11 probes, Earth’s position in shown in relation to 14 what?


The 14 objects on the Pioneer 10 and 11 plaques that indicate the location of our solar system are pulsars.


No trivia contest spoilers please!

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