A Las Vegas hotel magnate who is hoping to build the world’s first commercial space stations on Tuesday launched a challenge offering $50 million to the creators of the first privately funded spaceship to reach orbit. Robert Bigelow, who owns Budget Suites of America, formally announced the long-rumored prize just a day after the first privately funded spaceship rocketed out of the atmosphere and won the $10 million Ansari X Prize, which was designed to spur commercial spaceflight. To win the contest, which is limited to U.S.-based ventures, a team must build a five-seat spacecraft without government money and send five astronauts into orbit above the Earth twice within 60 days.