Going south to look for E.T. this week on planetary radio. Hi everyone, welcome to Public Radio's travel show that takes you to the final frontier and this week to Argentina. I'm Matt Kaplan. Our guest is the

director of Southern SETI, the only continuous search for extraterrestrial

intelligence in the southern hemisphere.

Guillermo Le Marchan will tell us why his project is uniquely exciting.

Bruce Betz is searching for a unique mineral called Armacholite.

You'll hear what he is dug up in this week's exciting

installment of what's up and Emily Lachto-Wala will be along shortly with a great new

space Q&A segment. We can only spare a few moments for Space News led by the return to Earth of Space Shuttle

Atlantis.

The crew made a safe landing on Friday at Edwards Air Force Base in the Southern California

Desert. Passenger Sunita Williams ended her nearly for space in the Southern California desert.

Passenger Sunita Williams ended her nearly 195 days in space aboard the International Space Station.

How does Space Craft manage to take beautiful pictures in near total darkness?

Emily wants to shed some light on that subject.

Here she is.

I'll be back in aala with questions and answers.

A listener asked,

How can Cassini take good pictures at Saturn when it's so far from the sun? Isn't it too dark?

It's true that a camera optimized for lighting conditions on Earth would have a tough time in the Saturn system.

Saturn is almost 10 times farther from the Sun than Earth is, which means that the Sun is about

a hundred times weaker there.

Fortunately, Cassini's engineers planned for the low light levels at

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