"I think this is going to raise fears about commercial space flight, but I think they are unjustified," said Howard McCurdy, a professor at American University who specializes in space policy and history. "There's a reason NASA has more than one commercial partner. I think there's a lot of redundancy or slack in the system. It's set up to handle these kinds of issues. You want everything to be perfect but it never is. Since it never is, the goal is to set up a system that can recover. That's what NASA has done."