A "pacy, smartly reported" (Financial Times) account of the historic quest to rekindle the human exploration and colonization of space led by two rival billionaires The Space Barons is the story of a group of billionaire entrepreneurs who are pouring their fortunes into the epic resurrection of the American space program. Nearly a half-century after Neil Armstrong walked on the moon, these Space Barons - Elon Musk, Jeff Bezos, Richard Branson, and Paul Allen - have founded some of the biggest brands in the world - Amazon, Microsoft, Virgin, Tesla, PayPal - and upended industry after industry. Now they are pursuing the biggest disruption of all: space. Based on years of reporting and exclusive interviews with all four billionaires, this authoritative account is a dramatic tale of the birth of a new Space Age. Detailing the rivalry between hard-charging startups and established contractors, The Space Barons traces the personal clashes of the leaders of this new space movement, particularly Musk and Bezos, as they aim for the moon and Mars and beyond.