Historic Las Vegas moments are usually wrapped in media-frenzied groundbreakings, landmark-dedication speeches or celebrity-filled casino openings. The fact that next week’s historic moment comes only with the ringing of telephones or the typing of credit card numbers makes it no less momentous. At 10 a.m. July 26, tickets for the Broadway Las Vegas series go on sale (starting at $99) for the Smith Center for the Performing Arts, which opens April 3, 2012, with The Color Purple, followed by Mary Poppins, Million Dollar Quartet and Memphis. No limos, no dignitaries with shovels, just a sign of progress in a city getting its first performing arts center.