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Planetary RadioAugust 26, 2014

Alan Stern and a Big Milestone on the Way to Pluto

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Alan Stern
Alan Stern

New Horizons Principal Investigator, Johns Hopkins University Applied Physics Laboratory

New Horizons passed through the orbit of Neptune on August 25th. By cosmic coincidence, this was the 25th anniversary of Voyager 2’s flyby of that big, blue world. We catch Principal Investigator Alan Stern right after a celebration in Washington. Alan also talks about the Rosetta comet mission and a new Uwingu initiative. Emily Lakdawalla shares a gorgeous new image of Neptune based on Voyager data. Bill Nye tells us why a major ground test of the LightSail solar sail was cancelled. Waiting for an easy space trivia contest question? This is your week!

New Horizons at Pluto

NASA / Thierry Lombry

New Horizons at Pluto
Artist's concept of New Horizons as it reaches Pluto.

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Trivia Contest

This week's prize is a Planetary Radio v2.1 T-shirt.

This week's question:

In Earth years, how long is a Pluto year?

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Tuesday, September 2, at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

What were the names of the five pocket mice flown on Apollo 17?


The answer will be revealed next week.

Question from the week before:

What two chemical elements, both discovered in 1803, were named after asteroids?


The two chemical elements discovered in 1803 and named after asteroids are Cerium and Palladium.

Listen more: New Horizons, Rosetta and Philae, Pluto, Planetary Society Projects, Cosmos-1, Planetary Radio, Neptune, Bill Nye

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