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Planetary RadioMay 12, 2015

Alan Stern and the Rise of Pluto

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On This Episode
Alan Stern head shot
Alan Stern

New Horizons Principal Investigator, Johns Hopkins University Applied Physics Laboratory

Humankind’s arrival at Pluto is barely two months away. The science and images have already started to flow from New Horizons, according to the mission’s Principal Investigator, Alan Stern. Alan returns to Planetary Radio this week. Curiosity has been busy on Mars, and Emily Lakdawalla has the complete story. Bill Nye is counting down to the May 20 launch of the LightSail solar sail, and Bruce Betts has the absolute truth about the absolute magnitude of our friendly, neighborhood star.

New Horizons Over Pluto

NASA / JHU-APL / SwRI / Steve Gribben

New Horizons Over Pluto
Artist's concept of the New Horizons spacecraft encountering Pluto and its largest moon, Charon (foreground) in July 2015.

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Trivia Contest

This week's prizes are a 200-point account worth $200 AND a stylish Planetary Radio t-shirt!

This week's question:

What galaxy was named after the larval stage of an amphibian?

To submit your answer:

Complete the contest entry form at or write to us at no later than Tuesday, May 19th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

In microns, how thick are LightSail’s sails?


The answer will be revealed next week.

Question from the week before:

What is the absolute magnitude of our sun?


The absolute magnitude of our sun is roughly +4.83. Use your sunscreen!

Listen more: New Horizons, Pluto, Planetary Society Projects, Charon, mission status, LightSail, Mars, Curiosity (Mars Science Laboratory)

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