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Countdown to Jupiter

Jupiter & Io from Cassini

Air Date: 06/28/2016
Run Time: 40:14

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Topics: mission status, Planetary Radio, the Moon, Chang'E program, Juno, Bill Nye, Jupiter

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Juno will enter Jupiter orbit on July 4th. Mat Kaplan talks with the mission’s Principal Investigator, Scott Bolton at the Jet Propulsion Laboratory. Bill Nye helps prepare us for this exciting encounter and the science that will follow. Emily Lakdawalla has the scoop on China’s next lunar mission—a rover on the Moon’s mysterious farside. And a Chinese mission from the past is at the core of this week’s space trivia contest on What’s Up.

Juno close to Jupiter

NASA / JPL-Caltech

Juno close to Jupiter

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Trivia Contest

This week's prizes are a Planetary Radio t-shirt, a Planetary Society rubber asteroid and a 200-point astronomy account.

This week's question:

What is the ratio of the equatorial surface gravity of the Sun to the force or pull of gravity at the surface of the Earth? (We’ll define the “surface” of the Sun as the edge of the photosphere or visible surface.)

To submit your answer:

Complete the contest entry form at or write to us at no later than Tuesday, July 5th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

What is the approximate ratio of the mass of Earth’s Moon to the mass of Pluto?


The answer will be revealed next week.

Question from the week before:

What was the name of the first human spaceflight of the Chinese space program? (In English, please.)


The first human spaceflight mission by China was Shenzhou 5 in 2003.


No trivia contest spoilers please!

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