There’s no shortage of laws governing what one can and cannot do in space (although some believe there should be more). But there’s one little snag that could land the burgeoning space tourism industry in a legal mire unless it is addressed soon – where exactly does ‘the sky’ end, and ‘space’ begin? An Australian professor has expressed his concerns that would-be turistas will want to be able to certify that they have indeed ‘been into space’ and not just ‘very high up in the sky’. Sounds a little specious when you put it like that, but it’s the sort of open question that gets lawyers foaming at the mouth.