((This Jan. 10 story has been corrected to rectify the payload capacities of SpaceX’s Falcon 9 and Falcon Heavy rockets in paragraph 12. A previous version erroneously stated the two rockets have ident) By Joey Roulette WASHINGTON (Reuters) – A Boeing-Lockheed joint venture’s launch of a new Vulcan rocket this week inaugurated a formidable rival to Elon Musk’s SpaceX, a milestone long sought by the U.S. government as it seeks to build a list of launch suppliers for its satellites. Boeing and Lockheed Martin’s United Launch Alliance sent Vulcan into space for the first time on Monday, a first s…