Virgin Galactic

As the space industry celebrates the 50th anniversary of Sputnik, the private sector is laying the groundwork for a new era of space exploration. Entrepreneurs expect the market will one day be worth trillions of dollars; that is, when space tourism is in full swing and people are mining other planets for minerals. For now, the primary market in space is in launching and operating communication satellites. And according to nonprofit space advocacy group the Space Foundation, space tourism could be worth between $600 million and $700 million in revenue by 2014.

Many companies hope to take the lead in the burgeoning market. From tourist trips to the International Space Station to erecting space hotels, these are some of the companies to watch.

Richard Branson, the billionaire behind the Virgin Group, is one of the more high-profile entrepreneurs in the commercial space market. Already selling $200,000 tickets to sports stars and royalty, his company Virgin Galactic isn't scheduled to launch its first trip until 2009.

Though the dates for Virgin Galactic's launch have slipped before and could again, Branson said earlier this year that timing matters little next to ensuring the safety and reliability of flights. Burt Rutan's Scaled Composites--which is under contract with Virgin Galactic to design and build its capsule and rocket--suffered a setback this summer when it lost several employees in a rocket-test accident.

When the operation is up and running, SpaceShipTwo, the design for which is shown here, will be launched from its mother ship, WhiteKnightTwo. After the mothership releases SpaceShipTwo at 50,000 feet, the craft will rocket to an altitude of 360,000 feet in about 90 seconds. At that height, passengers will experience weightlessness. The rocket's wings will then fold in preparation for re-entry into the Earth's atmosphere. The entire flight will take about two and a half hours.