This week's question:

What was the first Japanese lunar orbiter? Careful, this is tricky.

To submit your answer:

Complete the contest entry form at http://planetary.org/radiocontest or write to us at [email protected] no later than Tuesday, December 15th at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

What was the seventh moon discovered in our solar system? (After our Moon, the four Galilean moons, and Titan?)

Answer:

The answer will be revealed next week.

Question from the week before:

What was the only time a launch escape system was fired with a crew aboard while the rocket was still on the pad?

Answer:

Soyuz T-10a (or T-10-1 or 7K-ST No.16L) Cosmonauts Vladimir Titov and Gennady Strekalov were saved in 1983 from the explosion of their rocket by the launch escape system.