What do does it mean to have a commercial market for space travel and what benefits could come from having one?

The commercial market for space travel have generated multiple benefits for scientific experiments.

Explanation:

The flight of NASA astronauts onboard commercial spaceships to the International Space Station may be at risk, but the payoffs from low-cost flights to the orbital station and the increased experimental use of the microgravity environment are expected to be significant. Scientific studies, such as the production of vaccines, are now taking place onboard the space station, so providing more cost-effective means of entering earth orbit could fundamentally change other industries, such as medicinal and materials engineering.

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