The week after Richard Laronde returned home from a 16-day trek to the South Pole in January, he bought a ticket to outer space. For Laronde, who had also journeyed to the North Pole in 2006, making the decision to splurge $200,000 on one of the world's first commercial spaceflights took about as long as it takes to do a Google search for "space tourism." "As soon as I got back from the South Pole, I got on the Internet," said Laronde, 56, who owns a prospering event-planning business in Boston. Within days he had wired a $20,000 deposit to an accredited space travel agent in New York."Astronauts were my heroes growing up," said Laronde, who came of age in the early years of the U.S. space program. "It's always been a childhood dream."