Minnesota Astronomical Society

A nonprofit organization

16 donors

Since 1972, the Minnesota Astronomical Society (MAS) has been making the wonders of the cosmos available to the public.

The Minnesota Astronomical Society

From its humble beginnings in 1972, Outreach has been a cornerstone of the Minnesota Astronomical Society’s activities. Society volunteers have introduced the wonders of our universe to citizens of Minnesota numbering in the tens of thousand. Outreach events and activities over the years have included:

This society is organized exclusively for charitable, educational, and scientific purposes, to create good fellowship among all classes of people through mutual interest in astronomy. To promote membership and community knowledge about and involvement in astronomy through lectures, celestial observing sessions, classes and other appropriate means as well as establish and maintain observational and informational facilities for the benefit of the membership and the community.

The MAS currently has five Observing Facilities with dozens of scopes available for use by our more than 450 members and public outreach. 

Eagle Lake Observatory

The Eagle Lake Observatory is the main public outreach facility for the MAS.  Located just north of Norwood - Young America in Baylor Regional Park, the site consists of the Onan Observatory, the Sylvia A. Casby Observatory and the HotSpot Classroom.. The Sylvia A. Casby Observatory and the HotSpot Classroom became operational in the 2013 observing season and accompany the existing Onan Observatory which held its first public star party on April 28, 2000.

The Onan Observatory, has large assortment of reflecting and refracting telescopes as well as binoculars and solar viewing instruments.  The observatory is open to the public and MAS members at scheduled times during the year.

The Sylvia A. Casby Observatory houses an 8" TMB design refractor, a Takahashi Mewlon 300 Dall-Kirkham and a SV102 refractor. These telescopes set on an Astro Physics 3600 GTO mount, under a 12.5 foot Ash-Dome. Each observatory has the capability to display live video images of what the telescopes are viewing. These images are shown on monitors in each observatory as well as in the HotSpot Classroom.

The HotSpot classroom provides a much needed building to conduct our presentations as well as a warming room for our guests to relax throughout the night.

The MAS can boast of being one of the premier amateur astronomical organizations in the country, if not the world.  Along with the Eagle Lake facilities, The MAS has four additional observing sites available: Cherry Grove Observatory (CGO),  Metcalf Observing FieldJoseph J. Casby Observatory within the

Organization Data


Organization name

Minnesota Astronomical Society

Tax id (EIN)



Education Science, Tech & Business


PO BOX 14931