Ground control to Dr. Dave

DANIEL McCABE | The way kids were swarming around him after his lecture to get his autograph, you'd think Dafydd Williams had set a new record for home runs. Of course, Williams does have some impressive items listed on his resumé -- like travelling far higher than Mark McGwire could ever hope to hit a baseball. The Canadian astronaut and new director of the Space and Life Sciences Directorate at NASA's Johnson Space Center visited McGill, his alma mater, for a couple of days last week. Williams, who flew into space earlier this year as part of the crew of the space shuttle Columbia, met with medical students, visited with scientists at the Montreal Neurological Institute and presented a slide show about his adventures to an appreciative young audience on Saturday. Though he was born in Saskatoon, Williams grew up in Pointe-Claire, officially qualifying as "local boy makes good." He earned several degrees at McGill, a BSc, a master's in physiology, a medical degree and a master's in surgery. As a medical student, Williams won the Woods Gold Medal for outstanding clinical skills. The astronaut took along several tokens from McGill on his space voyage -- the Woods Medal, a Montreal Neurological Institute symbol and a McGill crest. "I spent a lot of time here, from 1971 to 1983. McGill is very much a part of my family and I cherished taking this out to space," said Williams as he displayed the University crest that orbited the Earth with him. Williams gave his audience a glimpse of life aboard the space shuttle. For one thing, weightlessness isn't very flattering for an astronaut's appearance -- they experience "puffy-face syndrome" as bodily fluids rush to their head in zero gravity. "When you eat in space, you can really play with your food," recounted Williams. "We could squeeze a blob of orange juice out of its container and watch it float around. Then you puncture the blob with a straw and just suck it up." One of his fellow astronauts, standing yards away, once tossed some M & Ms towards Williams. "They just keep floating in a straight line." And for those of you who wonder what astronauts eat in space, the menu includes shrimp cocktail, peach ambrosia and beef tips with mushrooms. Blasting off was an uncomfortable experience. During the launch the astronauts contended with tremendous pressure that was up to three times the force of gravity. "A tight turn on a roller coaster is two times the force of gravity," Williams related as a point of comparison. "You feel like there is an elephant sitting on your chest." The sleep stations look like small closets -- long and narrow. According to Williams, even in a weightless environment, astronauts still feel the compulsion to move about from side to side as they float in their sleep. The natural sleeping position in space involves having your hands float in front of you -- which results in astronauts often waking up from dreams in which they're fending off someone trying to grab them. There was a serious side to Williams's time in space, of course. The theme of the mission was neuroscience and Williams engaged in several studies. One, which used baby rats, looked at sensory adaptability, posing the question: Could baby rats learn how to walk in a weightless environment? The answer was yes -- by gripping tightly to a narrow walkway, and using their limbs to push themselves forward. Back on Earth, after an initial spell of awkwardness, the young rodents learned to grapple with gravity fairly easily. "The mechanisms in the nervous system that are responsible for this can re-adapt to a totally unique environment," said Williams. The data from the experiments is still being analyzed. The first presentation of the results of the studies should take place in the spring. How do astronauts go to the bathroom? queried one young audience member. "Very carefully," quipped Williams. "While they're training to go into space, astronauts spend time with something called, believe it or not, a toilet training simulator." When an astronaut needs to use the facilities in outer space, "a vacuum makes sure that everything goes in the right direction," said Williams. "Nobody wants to be the astronaut who breaks the toilet in space. The back-up plan involves little baggies. You just don't want to do that. "Often people ask me, 'What can top that?'" Williams says of his space adventure. "I think it's important to keep dreaming." Williams's dreams are now tied to the future of the space program. Scanning the roomful of seven- and eight-year-olds, Williams said, "That's the age I was when I first started thinking about being an astronaut." Work will begin on the International Space Station later this year, Williams related. "We'll go back to the moon, this time for a much longer period of time. We'll build lunar outposts. We'll send a crew to Mars. There are no ifs around it. It's going to happen." In his new position, Williams will help plan for such a trip. "It would take six months to get there and six months to come back. It raises all kinds of questions for us. What do we do if an astronaut has appendicitis on Mars?" Williams has a more immediate assignment to contend with. Later this month, another space shuttle mission will begin -- one with historic significance. Seventy-seven-year-old U.S. senator John Glenn, one of the first astronauts ever to venture into outer space, returns to the cosmos. Some of the research planned for the trip will focus on the effects of weightlessness on old age. "I'm in awe," said Williams. "I grew up watching John Glenn on TV. He was one of my heroes. And now here I am, responsible for the life sciences experiments that will be taking place when he goes back up." Williams's presentation on Saturday was sponsored by the McGill Society of Montreal.