Photo by Barb

Star parties (observing sessions) for the public are regularly scheduled in the summer at our Hidden Valley Observatory, and sometimes for private groups as needed.  Also, star parties are sometimes held for members only at various dark-sky locations, and, if conditions warrant, the public might be invited to one of these.


Summer (May or June through August or early September) star party workshops (observing sessions) for the public are scheduled on Friday nights dependent on the phase of the Moon.  Please note that these are held "weather permitting", i.e. the event is cancelled if the weather is rainy, cloudy, or excessively windy. We usually begin each observing session starting at about 9:00 P.M.  Cancellations and postponements due to weather are posted on our homepage.

Private star party workshops may be arranged for private groups, summer or winter, by contacting our Observatory Director (see our home page).  However, before requesting a private workshop, please review the section titled REQUESTING A PRIVATE STAR PARTY WORKSHOP posted below.

The public star party workshops are normally announced well in advance on our calendar of events open to the public which is posted here.  However, they may be announced at any time with short notice on our home page.

Getting the Most out of the Workshop

In order to provide everyone with the best possible experience at an observing session, please take a moment to review the following guidelines.

Flashlights: If you wish to use a flashlight, please cover the end with a red balloon or a red filter. You may not realize it, but after you have spent about 20 minutes in the dark your eyes adjust to the darkness allowing you to see much fainter light. It only takes a fraction of a second of looking at a bright light, especially if it's not a red light, to destroy the dark adaptation and you will then need to wait before you can again see clearly in the dark.

Food and drink: "Sticky fingers", (Rolling Stones album) crumbs, and liquids can damage equipment. If you need to eat or drink while at a star party, please keep a short distance away from the telescopes, and clean your hands when you are done. Alcoholic beverages are NOT PERMITTED at our workshops. Please deposit your trash in a waste bin, or take it with you.

Look With Your Eyes and Not With Your Hands:  Do not place your hands on the telescope. This will cause the telescope to move and the object you should be viewing will move out of the field of view.

Parents, please mind your children: The safety of your children is important to us. Running around in the dark is not safe: it's easy to trip on things. We don't want anyone to be injured, or any equipment to be damaged.

Vehicle Headlights: Please turn off your headlights when arriving at the workshop so you will not temporarily blind someone. The best practice is to arrive before twilight ends, and park your car so that it will be facing away from the telescopes and other people when you leave.


Cell phones: Please keep in mind that you will need to avoid exposing other people to the bright screen that most cell phones have - that light will be enough to deprive other people of their night vision adaptation for many minutes.  Also, please be considerate of other people not wanting to overhear your conversation.

Photography:  Flash photography is NOT allowed until after all observing has ended.  Keep in mind that most point-and-shoot cameras and cell phones will respond to darkness by using flash.  Even one flash can rob others of their visual adaptation to the dark.



The Black Hills Astronomical Society has, as one of its missions, the dissemination of scientific knowledge concerning astronomy. To further this mission, BHAS offers "star party workshops" (observing sessions) at our Hidden Valley Observatory on selected Friday nights in the summer to which the public is invited. In addition, we may have a public session for a special astronomical event.  A private workshop for a group may be possible at our observatory or another location with the following considerations in mind.

Locations other than our observatory should not be exposed to nearby lighting unless the lights can be, and will be, turned off. This also means that a location swept by the headlights of passing vehicles is not acceptable. The selected location must have a clear view of the sky, and an adequate area of flat ground to accommodate the participants and the required telescopes. Liability for any injuries or property damage at a location not under the control of the Society cannot be assumed by the Society. If young children will be present there must be enough adults present for their supervision to insure their safety.

The proposed date and time of the workshop should be selected with the reality of astronomical observations in mind. Nights when the Moon is full, or near full, are to be avoided since moonlight will wash out objects of interest. Outdoor activities are always subject to the possibility of adverse weather. Having  an alternative date or program in your plan is a good idea.

Please note that our workshops rely on BHAS members donating their time, expertise, and the use of their expensive and delicate instruments in addition to any BHAS equipment that may be used.

The Society charges a modest support fee for private workshops in order to offset our costs and to support our activities.  No compensation, however, is given to any individual. Any additional donation to the Society is gratefully accepted as is any form of public acknowledgement of our efforts.

Support Fee schedule:
Fewer than 7 people -     $35.00
Seven to 14 people -       $50.00
Fifteen to 25 people -      $75.00
26 to 50 people -           $100.00
51+ people -                  please contact us
If at a location other than HVO, an additional charge will be applied.

Payment and cancellation: The fee is due at the start of the workshop. However, if the requesting party cancels the workshop with less than 24 hours notice the fee is still due. After receiving a confirmation email from the Observatory Director a $5.00 non refundable reservation fee is required to secure the requested date.  This fee is applied to the total cost for the event, it is not ‘in addition to’. In the event the workshop is canceled due to weather, rescheduling may or may not be possible and will have no priority.

To request a private workshop, please contact our Observatory Director (click here to send an email)
Scheduling is done only by the Observatory Director, and requests are considered on a first come first served basis. Please understand that the number of workshops we can schedule in a given period of time is limited.