MarkWhittington writes "Neil deGrasse Tyson, the famous astrophysicist and media personality, offered something of a reality check on the potential of commercial enterprises to open the space frontier without the aid of government. Specifically referencing SpaceX's CEO Elon Musk's boast that he would establish a Mars colony, Tyson said on a recent video podcast, 'It's not possible. Space is dangerous. It's expensive. There are unquantified risks. Combine all of those under one umbrella; you cannot establish a free market capitalization of that enterprise.'"