When kids ask Dan Tani what it takes to be an astronaut, he smiles and says good grades are a plus, but even more important, "you have to be nice enough that someone would want to live with you in a tin can for six months."

Speaking Friday to a roomful of children at the Salt Lake City Library, Tani described his latest mission to space — a four month stay on the International Space Station.

"You can tell which one I am in space, because I am the one with a big smile on my face," he said.

Tani was speaking as part of his attendance of the 2008 Japanese American Citizens League national convention. Tani is set to deliver the keynote address at the downtown Marriott for the civil rights organization.

Tani, whose parents were both interred at Topaz near Delta during World War II, told the Deseret News that JACL is active today in ensuring "we've learned our lesson as a nation," so the suffering that interred Japanese Americans suffered more than half a century ago isn't repeated.

In particular, today, Tani said, JACL is outspoken against the prevalent anti-Muslim attitude.

Tani, who has been an astronaut since 1996, has flown in space twice. He returned from his most recent mission in February. On that trip, he was part of a team that installed a node on the International Space Station, to which research labs will be attached.

On Friday he fielded questions from kids, ranging from how he sleeps in space and if they ever worry about the shuttle running out of gas.

Since it goes from daylight to darkness every 45 minutes, Tani said, you have to close the shutter to keep it dark, and you sleep in a sleeping bag that's clipped to a wall so you don't float off.

As for fuel, he said, the goal of landing a space craft is actually to burn off the fuel before it lands.

Kids giggled as he described the few times when weightlessness is difficult, such as when bumping against things while learning to "superman" through the shuttle. And, Tani, described the process of anchoring down for tasks as simple as using a screw driver.

"Space is unbelievably fun," he said. "Seventy-five percent of the time weightlessness is fantastic. And 25 percent of the time, weightlessness is a pain in the neck."

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