The 20th-century was marked by competition between two Cold War adversaries, the Soviet Union (USSR) and the United States, to achieve superior spaceflight capability.

The space race led to great technological advances, but these innovations came at a high cost. For instance, during the 1960s NASA spent $28 billion to land astronauts on the moon, a cost today equating to about $288 billion in inflation-adjusted dollars.

In the last two decades, space startup companies have demonstrated they can compete against heavyweight aerospace contractors as Boeing and Lockheed Martin. Today, a SpaceX rocket launching can be 97% cheaper than a Russian Soyuz ride cost in the ’60s.

The key to increasing cost efficiency?

SpaceX rocket boosters usually return to Earth in good enough condition that they’re able to be refurbished, which saves money and helps the company undercut competitors’ prices.