In his book "Roving Mars, " Squyres recalls the first time he saw Pancam pictures on Mars.

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" Nobel Laureate Steven Weinberg calls manned missions "an incredible waste of money" and argues that "for the cost of putting a few people on a very limited set of locations on Mars we could have dozens of unmanned, robotic missions roving all over Mars.

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Even if the delicate digital hardware running these machines keeps going, and even if they are the smartest roving robots this side of Mars, navigating through the scrub, dust and rock of the Mojave desert represents a complex challenge.

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Ira Flatow will be here to talk about a new study about life expectancy in the U.S. And the Mars rovers are still roving nearly three years into what was supposed to be a three-month mission.

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It's supposed to go into orbit for a couple of years, taking these incredible close-up pictures, and you probably remember, Madeleine, that there's two little rovers that are still roving around on the surface of Mars, and they're still working great and sending back pictures.

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