I recently saw some comments under a YouTube video asking why we don’t postpone going into space until we’ve solved our problems on Earth (which would be a pretty long postponement). This is a question people have asked for decades, and it arises in part from an inaccurate notion of the cost, just as many people incorrectly assume that a high percentage of the U.S, budget goes to foreign aid. It also overlooks the important role of space research in dealing with the problems we have on Earth, but for the moment let's focus on the cost question, starting with a couple of examples.
New Horizons is the space probe that flew past Pluto and its moons in 2015 and later visited on object in the Kuiper Belt. Building and launching the spacecraft cost $565 million, with operations through the Pluto flyby and subsequent collection and analysis of the data by teams of scientists adding another $215.6 million.
This means that over the 17 years of the primary mission, the total cost of New Horizons—a little less than $800 million—averaged less than $47 million per year, or 0.0000015% of U.S. federal spending over those years. That’s 15 ten-millionths of one percent. This is roughly the median cost for a U.S. robotic space mission.
Mars Global Surveyor was an orbiter launched in 1996 that operated for 10 years and was one of the most successful missions of its type. At the time, someone at NASA created a poster showing a series of comparisons between Mars Global Surveyer and the 1995 movie Waterworld. For example, a major goal of Mars Global Surveyor was looking for water, while people in Waterworld would have liked some dry land. The main expense of the former was scientific instrumentation, and of the latter, Kevin Costner. I forget the rest, but the bottom line was a comparison of costs: $154 million for Mars Global Surveyor versus $172 million for Waterworld (actually closer to $235 million for the latter if you include prints and advertising).
Sending humans into space is much more expensive than sending robots. A single launch of the new Space Launch System rocket, under development for NASA’s Artemis project to return astronauts to the Moon, is likely to run nearly a billion dollars, at least initially. A SpaceX Crew Dragon launch carrying astronauts and cargo to the International Space Station (and ultimately back) runs about $400 million.
For comparison, the major video streaming services are spending about $30 billion per year on producing films and series. (That doesn’t count production costs for theatrical movies, broadcast and cable television, etc.)
NASA accounts for less than half of one percent of current federal spending. If you compute the grand total of NASA’s budget for every year from its founding in 1958 through the present, adjusted for inflation, the sum is not much more than U.S. defense-related spending for a single year. (See this earlier post for a graphic illustrating this.)