'Facing Mars' exhibit tests your readiness for space

"Earth or Mars?"

That's the question posed to visitors as they enter Pacific Science Center's new exhibit, "Facing Mars," a question that has two sides to it.

The first involves personal inclination: Which planet would you rather be on? Visitors vote their preference by choosing between "Earth" and "Mars" gates as they enter the exhibit. (At the exit, after you've seen the displays, you can vote on the question again.)

The second concerns powers of perception: A widescreen TV flashes image after image of arid terrain. The photographs are captionless for 8 seconds, allowing visitors to guess whether it's Earth or Mars they're seeing. The answer, when given, is almost always a surprise. The Atacama Desert, sand dunes of the Sahara and McMurdo Dry Valley of Antarctica can look awfully Mars-like to the untrained eye.

Fine presentation and an innovative approach to visitor participation distinguish "Facing Mars," created by Canada's Ontario Science Centre and on tour throughout the United States through 2012. There's plenty to attract curious kids — and a lot for adults to learn, too, if you haven't been keeping up with your Mars facts and figures or the practicalities of space travel.

Toilets, for instance: "There's nothing simple," we're told, "about going to the bathroom in space."

I guess we knew that, but Canadian astronaut Chris Hadfield, with a light, personable touch, explains just what the complications are. One fact new to me was that water vapor from astronauts' breath and sweat constitutes as much of a disposal problem as urine, feces and, ahem, gas.

Facts about Martian weather, the Martian atmosphere and Martian gravity are all clearly presented. The geological history of Mars — what we know of it — is outlined, including the reason it's home to the tallest mountain in the solar system. The correct color of the planet — more a "butterscotch hue" than the proverbial red — is also given.

Interactive exhibits include simulations of what it would be like to walk on Mars or glide over the planet in search of evidence of water. And the challenges of getting there and back are also addressed.

Food, of course — how much you can bring with you, how much you can grow there in greenhouses — would be a problem. (The vacuum-sealed packets of scrambled eggs, chicken salad and creamed spinach on display look far from appetizing.) Difficulties with face recognition in zero gravity are a more unexpected wrinkle. Apparently it's tough for humans to recognize a face that's floating upside down: a fact vividly demonstrated with a startlingly grotesque graphic.

The "primary physical obstacle" preventing humans from going to Mars, however, is the debilitating bone loss induced by long stints in microgravity conditions. The accidental fracturing of a limb would put an astronaut in a real fix: "Currently scientists don't know if broken bones can heal in reduced gravity."

And there's the cost. Getting humans to Mars would run roughly $50 billion. One skeptic, shown on video in the exhibit, wonders why you'd spend so much money going to a dead planet when you could be trying to fix the planet we're ruining here.

Michael Upchurch: mupchurch@seattletimes.com