Somewhere between ambition and orbit, AST SpaceMobile is buying itself time. The company has raised $1.15 billion in convertible bonds, bringing its total liquidity to $3.7 billion — enough, by management's reckoning, to carry a 45-satellite constellation from construction floor to commercial sky by 2027. In the long arc of the space economy, this is the familiar story of a challenger marshaling capital against the clock, betting that pre-arranged partnerships with major cellphone carriers will matter more than being first.