Though today’s political climate is reminiscent of a time when the world’s eyes were on the two sides of the Cold War, the days when space exploration was dominated by the US and the Soviet Union are long gone. In addition to the US’s NASA and what is now Russia’s Rocosmos, several major powers have their own important space agencies. The European Space Agency (ESA), the China National Space Administration (estimated here because of the relative lack of data provided by the Chinese government), the Indian Space Research Organisation (ISRO) and the Japanese Aerospace Exploration Agency (JAXA) make up the rest of the world’s six largest space agencies. Though each have seen projects of importance to humankind’s ascent to the skies, NASA’s budget is by far the largest, outstripping all five others combined. NASA’s funding has always been astronomical, though its current $19bn size is something of a recent feature. It hasn’t had this much to play with since the early 1990s, with a figure of around $16bn (held constant to 2009 prices) the norm for almost two decades after that. Since 2013 though, NASA’s budget has increased by more than $2bn, particularly as it gears up for more pivotal missions to Mars.