Overwhelmingly huge. Very expensive. No comparison...

Overwhelmingly huge. Very expensive. No comparison with other science museums, it's the archetype for all modern interactive science museums. When it was created by Frank Oppenheimer (J. Robert Oppenheimer's younger brother), it was a participatory, hands-on, hippie kind of thing. Most of the original exhibits were made out of recycled surplus and junk.
Now, a nominal few of those original exhibits are banished to obscure corners of the museum. The space is dominated by expensive corporate-sponsored professional shows that are cold and not-so-interactive.