Why was the space station built in orbit instead of on the Moon?

Answer 1

Low earth orbit is closer, can be reached more efficiently (less expensively) and meets mission objectives of performing scientific experiments and observations in microgravity. A moon orbiting station would be more expensive to maintain, increase risk to the crew aboard and crews servicing it, without added benefit to the mission of the station.

To date there have been 6 manned missions to the moon, and 20 missions to the International Space Station which has included numerous Space Shuttle and Soyuz missions providing crew, supplies and segments of the station.

Answer 2

Building a space station in Earth's orbit was more practical due to proximity to Earth for supply missions, lower gravity for easier construction, and easier crew rotations. Building on the Moon would have been more challenging and expensive due to the Moon's distance, lack of atmosphere, and the need for more advanced technology and infrastructure.