Calvin Observatory

Basic information


  • Calvin Observatory
  • Grand Rapids, MI 49546
42.931015 -85.58867
View on campus map Get directions

Calvin boasts access to two fully-equipped observatories, one on Calvin's campus and a robotically-operated telescope in Rehoboth, New Mexico. The central mission of the Calvin College Observatory is educational, and the telescopes are used by students at all levels from first year non-science majors to fourth year physics majors.

The laboratory portion of most Calvin astronomy classes contains some "new science" project. Dedicated telescopes of modest aperture are especially well suited to contribute to the study of objects that vary in position or brightness with time.

Observatory equipment

Both sites

Telescope: Optical Guidance Systems RC16-75F with carbon fiber tube
Guidescope: Takahashi refractor FS-78, 3" diameter
Guide camera: ST-237
Slide Mirror: Van Slyke Engineering Versaport Slider
Dome automation:
Meridian controls solar powered, computer controlled dome motors
Power automation: X10
Telescope control software: Comsoft PC-TCS
Planetarium software:
Software Bisque TheSkyX
Camera control and image processing software: Diffraction Limited Maxim DL
Astrometry software: PinPoint (from DC-3)
User interface: ACP ASCOM DC-3 Dreams (Astronomy software)
Remote operation: RealVNC
Rack to support camera: custom built

Calvin-Rehoboth Telescope near Gallup, NM

Dome: Ash Manufacturing Company 10'6" diameter REB dome
Camera: Santa Barbara Instrument Group ST-10XE
Filter Wheel: Two Optec IFW wheels with 2" filters (UBVRI, H-alpha and red continuum)
Focal Reducer: Optec WideField 0.62X Telecompressor
Web cam:
TRENDnet TV-IP612P (installed May 2011)

Calvin Observatory in Grand Rapids, MI

Dome: Astro-Tec 15' diameter
Video Camera: Astrovid StellaCam3
Camera: Santa Barbara Instrument Group ST-8XE
Filter Wheel: Santa Barbara Instrument Group CFW-8 with 1.25" filters (UBVRI, H-alpha and red continuum, O III and green continuum)
Focal Reducer: Optical Guidance Systems 0.63x
Spectroscope: Santa Barbara Instrument Group Self-Guided Spectrograph, mounted with SBIG ST-7E camera

Also used in the Calvin Observatory:

Two Meade LX-90 telescopes 8" f/10 x2
Binoculars: A Celestron 7x50 and an Orion 10x70.


Calvin Observatory is open to the public on clear Wednesday evenings throughout the year (excepting only the last two weeks of December). All are welcome. Larger groups should call the observatory director (Prof. Larry Molnar, 526-6341) in advance. If in doubt about the weather, you may call the telescope dome at 526-6435.

Summer hours
During the summer, the observatory is only open on clear Wednesday evenings, and all are welcome. The dome opens one hour after sunset, and remains open until midnight. See the calendars below for sunset times.

Fall and spring semesters
During the fall and spring semesters, the Observatory is open to Calvin students clear evenings Monday through Thursday, and to the general public on Wednesday nights. The dome opens at 7:30 pm or one half hour after sunset (whichever comes later), and remains open until 11 pm. See the calendars below for sunset times.

Christmas break
The observatory is closed over Christmas break: the last two weeks of December

During January interim, the observatory is only open on clear Wednesday nights, and all are welcome. The dome is open from 7:30 to 11 pm.


Wheelchair access: Although the Calvin dome, constructed in 1969, is not accessible by wheelchair, we have portable telescopes. Viewing sessions will be arranged on request. Call the observatory director (Larry Molar, 526-6341) to arrange time and place

Starting at west parking lot crosswalk near the large yellow and orange sculpture (see the “DeVries Hall” label on the map), take the paved walk between DeVries Hall and the Spoelhof College Center. Rather than taking the long ramp directly up to the DeVries Hall / Science Building entrance, stay on ground level by taking the right fork and continue walking around the Science Building’s south and east sides until reaching a sign saying "North Hall." Enter the first double set of double glass doors (red arrow on map). Don't enter North Hall, but enter the stairwell door bearing a sign “Observatory, 4th Floor” immediately to your left. (GPS coordinates: approximately 85.58861 degrees west and 42.93126 degrees north, WGS84 map datum.) Then climb the stairway three flights to the roof level.

There is an elevator from the ground floor to the third floor, leaving just the final flight of steps to the roof level. Until 10 PM it may be reached by going forty feet down the hall to the left, and turning right at the overhead sign "elevator". Exit the elevator corridor on 3rd floor, turning left to the stairwell door. Proceed up the final staircase to the observatory. The other doors should be open until 11 PM. If outer or lower stairwell door is locked, call 526-6435 or 526-8847 to speak to the observers on duty.



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