The Planetary Report • September/October 2004

A Halo of Moons

On the Cover: Saturn wears a halo of four moons in this Wide-Angle Camera image taken by Cassini on August 18, 2004. The satellites visible in this picture are (clockwise from upper left): Tethys, Dione, Enceladus, and Mimas. This portrait was captured in visible red light at a distance of 8.9 million kilometers (5.5 million miles) from the planet. This black and white image was colored blue and gold. To view the original image, go to


7 Robots, Not Humans, on Mars: Andy Ingersoll urges The Planetary Society to prioritize scientific exploration over human exploration of Mars.

8 Out of This World Books: Planetary Society books reviews are back by popular demand, just in time for the holiday season!

12 Cassini Captain's Log: 2004.184: Carolyn Porco, the Cassini Imaging Team leader, shares her personal account of how it felt to finally reach the lord of the rings and shows off some of the best images so far of the awe-inspiring ringed planet.


3 Members' Dialogue Robots or humans?

4 We Make it Happen! An update on SETI

6 Society News International Space University fellowships, Planetary Radio, and volunteer efforts

19 World Watch The future of the space shuttle and the International Space Station

20 Q&A How did the scarp around Olympus Mons form? How do the MER soil tests compare to Viking's results?

The Planetary Report • September/October 2004

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