What organization is credited with building the Spacelab?

The European Space Agency (ESA) is credited with building the Spacelab, which was a reusable laboratory designed to be carried on the Space Shuttle. Spacelab was pivotal in enabling scientific experiments in a microgravity environment, significantly contributing to our understanding of various fields such as biology, materials science, and astronomy.

ESA's involvement in the development of Spacelab showcased international collaboration in space exploration, as it was constructed in partnership with NASA but ultimately designed and built by ESA. This collaboration allowed astronauts from different countries to conduct research in a unique orbital laboratory.

NASA played a crucial role in operating and deploying Spacelab aboard the Space Shuttle missions; however, the agency did not build Spacelab itself. Other organizations mentioned, like Roscosmos and Northrop Grumman, were not involved in the Spacelab project, as they focused on different space exploration initiatives.