Mars One, the non-profit group planning a one-way trip to the red planet in 2025, got lots of media attention this week when it announced it had narrowed its pool of potential astronauts to 100 candidates from around the world. But there are 6 billion reasons to believe they won’t make it. I refer, of course, to the $6 billion budget Mars One says will be required to lay the ground work for and launch its first manned mission. We’ll assume that $6 billion is enough money to meet its goals, although space projects are notorious for cost overruns and delays. Even then, it’s not clear that Mars One will be able to collect close to that amount and meet the mission goals. “We do not disclose these numbers at this time,” Bas Lansdorp, the CEO of Mars One, said in an e-mail. Start with what’s expected in the near term: Per Mars One’s timeline, it plans to open a simulation colony here on Earth this year, so their astronauts can begin training for the mission. While the organization announced plans to start building, it has yet to reveal the location or any further details on construction. “We’re still on track to have that ready after the summer,” is all Lansdorp would say. More reasons via Quartz.