Investors eager to own a piece of Space Exploration Technologies Corp. (SpaceX) could face a very long wait. According to a recent tweet from the Hawthorne, Calif.-based company’s founder and chief executive, Elon Musk, there will be no initial public offering (IPO) of SpaceX stock before humans have begun to settle Mars. “No near term plans to IPO SpaceX,” Musk wrote in a short message posted to Twitter June 6. “Only possible in very long term when Mars Colonial Transporter is flying regularly.” The Mars Colonial Transporter is a conceptual vehicle that Musk has discussed as part of his company’s stated long-term goal: sending human settlers to Mars. This is a change in tone for Musk, who up until the June 6 tweet had said that SpaceX would go public in the near-term, as his other two companies, Solar City and Tesla Motors, have. As recently as February 2012, Musk told Bloomberg News that he might take SpaceX public in 2013.