Welcome

The Horwitz - DeRemer Planetarium

  • From our Director:
    Well, it is official. We will be opening on Wednesday, July 8th for our Wild Wednesdays. We will plan on running Wild Wednesdays for the rest of the summer. A few differences, though, will be that it will only be pre-registration. Pre-registration must take place through the County website. Show size will be maxed out at 22 individuals. This is the number that we believe we can support and still adhere to the CDC guidelines set forth at the point of this newsletter article. I can’t say for sure that things won’t change as one thing that we have learned for sure is that these last few months have caused everyone to be very fluid with their planning. Our first priority is the safety and wellness of our guests. Seats will be assigned to ensure social distancing the best way possible. Masks are highly recommended.    See calendar for Wacky Wednesday Schedule.


    The original School District of Waukesha Charles Horwitz Planetarium opened in January 1978 and named after Mr. Charles Z. Horwitz, a well-respected Science Teacher, Principal, and Science Director for the School District of Waukesha.

    A new planetarium was built in 2005 to replace the original facility and is located in Waukesha County’s Retzer Nature Center. In the Spring of 2018, the planetarium was renamed. David A. DeRemer was director of the planetarium from 1978 to 2018. In 2005, Dave received the Lifetime Excellence in Education Award from the Waukesha Education Foundation and was instrumental in fund-raising, planning, and building the new planetarium. To honor Dave’s commitment to the success of the planetarium and to recognize his dedication to the students and community of Waukesha, the “Friends of the Planetarium” and School Board of Waukesha voted to rename the planetarium the Horwitz – DeRemer Planetarium.

    The planetarium is not only an accurate day and night sky projection system, but the program serves as a district and community science resource center. School and community programs are designed to meet state and national astronomy standards, but these programs also present fundamental science concepts of weather, climate, chemistry, physics, and earth science.

    A Community Resource (Retzer Nature Center)
    The planetarium shares a cooperative agreement with the Waukesha County Park System to serve the community as a local earth and space science resource. With the emphasis on family programming, the planetarium presents daily and weekend astronomy shows to the public. The planetarium is also available for private groups such as scouts, church groups, birthday parties, science clubs, senior citizens, or daycare centers. Regular public sky-watching sessions are provided by the planetarium, providing members of the community opportunities to observe sky objects through telescopes and binoculars.

    To visit their website CLICK HERE.

Retzer building
  •  Where is the Planetarium?

    We are located within the
    Retzer Nature Center
    S14 W28167 Madison St.
    Waukesha, WI 53188
    Horwitz DeRemer
    Planetarium
    Phone: 262-970-4139

    The Planetarium has a maximum seating capacity of 90 chairs, plus up to 10 wheelchair accessibility. Advance purchase tickets are capped at 60 seats, with up to 30 seats available on a first-come, first-served basis payable at the door.

Upcoming Events

View Calendar