Crossing over, but distinct from the communications segment, is the satellite segment. Satellites are often used for commercial communications, but can also relate non-commercial purposes such as military use or scientific research. Global revenue from satellites totaled 269 billion U.S. dollars in 2017, with 91 new satellites launched in that year. In recent times, the number of satellite launches has declined from the industry’s peak between the mid-1960s and late 1970’s, when an average of 128 satellites were launched per year. In 2017, there were 1,900 satellites in orbit, of which 859 belong to the United States.
Another third way to divide the space industry for analysis is by contrasting private and government spending. In 2016, government spending comprised around 25 percent of the total global space economy, amounting to some 84 billion U.S. dollars. The United States government is the largest contributor, with NASA’s budget being over 19 billion dollars in that year. Other major government players are the European Space Agency and China, however their combined spending in 2017 was only 10.7 billion dollars – just over half of NASA’s spending for the same period. Of NASA’s budget, around half is spent on space exploration, with the remainder being spent on a variety of scientific, educational, engineering and administrative functions. However, public opinion is that NASA should focus more on research, technological development and threat prevention than space exploration. In a 2018 survey, only 18 percent of U.S. adults believe that sending astronauts to Mars should be a top priority.