The planetarium (which serves the entire district) opened in 1974 and in 1978, the west wing opened, which was similar to the east wing, but had two levels.
The planetarium (which serves the entire district) opened in 1974. The west wing opened. This was in 1978. The west wing had two levels. This was in 1978.1978 was similar to the east wing.1978 was the west wing. This west wing was opened.