Mount San Antonio College Randall Planetarium

1100 North Grand Avenue
Walnut, CA 91789


The Randall Planetarium at Mt. SAC has been serving the community for nearly 40 years since opening its doors in 1968. The facility is used as an instructional facility (astronomy classes, presentations to local schools) and for public productions that open our remarkable galaxy to the community at large. The Randall Planetarium facility has a 35-foot-diameter hemispherical dome and seats up to 75 persons.

More than 1,500 astronomy students per year use the facility as a learning lab, and over 6,000 school children per year come to explore the stars and planets.

Thanks to donations from The Foundation, individuals, students, and the community, the planetarium was renovated and re-opened in December 2010 with a new Digistar 4 digital star projector to explore the solar system, and view brilliant nebulas as well as a Zeiss SKYMASTER ZKP 4 for focused stunning star-lit skies. Enhanced with surround sound the newly Mt. SAC Planetarium now provides a truly immersive planetarium experience.

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