Observatory Rules

(adapted from Observing Field Etiquette, composed by Jay McNeil)

This article may seem detailed, but it essentially focuses on two things: dark adaptation, and respect for observing equipment. Remember this as you read these Observatory Rules.

First, do no harm.  Our use of the old Muscle Shoals Astronomical Society observatory is both an in-kind civic project and a partnership with LaGrange Living Historical Association. Our first goal is to respect and steward the LaGrange College Historic Site, and to maintain close contact with its Board of Directors.

Do you have a telescope or binoculars? Bring them! No matter if they are unfamiliar, unknown or complex, you will definitely find help with our group.


In the absence of white light, the human eye takes roughly 45 minutes to fully dilate the pupil to a diameter of 6 and 7 millimeters.  This dilation is lost instantly in the presence of white light, so all light sources should be covered with a red filter, or hidden completely. Red is the only color that preserves the eye’s dark adaptation. To navigate at night, prepare a flashlight with a red filter or lens, and always point it toward the ground.  Filters can be purchased at hobby stores or in the automotive section of many retailers.

Vehicle lights may start automatically when the car is started. Some vehicles can bypass this feature, others cannot. Please park your vehicle with headlights pointing away from the field or observatory. Also consider the glow from interior dome lights.

Smartphones can take great pictures at the eyepiece, but only when dark-adapted vision isn’t required, like during sidewalk astronomy.  Smartphone displays in “red light” mode still phosphoresce in the full visible spectrum. When “red light rules” are in effect, please keep phones hidden at all times.

If you absolutely must bring out your phone, or turn on a white light, call out “White Light!” to warn other astronomers, then wait fifteen seconds before switching on the light source.


No flash photography! The bright strobe of a camera flash will instantly ruin dark-adaptation, This includes flash reflection, because white light is white light. Take a moment to turn off your smartphone’s camera flash as a precaution. Natural light photos are welcome, as is all astrophotography, of course!

Aerosol Sprays

Do not bring aerosol sprays to the observing area. Both the chemicals and propellants can permanently damage telescope optics. If insect repellents are necessary, please only use lotions or wipes.

Food and Drinks

Food and drink must only be consumed at the Pavilion. No food or drink is permitted in the Observatory. Alcohol is strictly prohibited in the LaGrange College Historic Site.


Do not smoke on or near any observing area. Smoke will damage telescope optics by settling on and soiling the coatings. Telescope mirrors and optics represent an investment on the part of the owner.  Regardless of cost, owners hate to see their telescope optics dirtied by tar from cigarette smoke.

If you must smoke, please move to an area away from the observing field and downwind of the telescopes (at least 50 feet). Please respect the facility, and only discard butts in proper containers.

Don’t spark a lighter near observers.  If you must light up, go behind a large vehicle or otherwise thoroughly shield your flame. A lighter is just as luminous as a white flashlight.

Smokeless tobacco is also prohibited. Astronomers may need to get on their hands and knees to service equipment (even in the dark!), and no one deserves to encounter tobacco spit this way.


Some observers enjoy playing music while looking through their scopes. This is acceptable under certain circumstances. Please respect your neighbors by asking before turning on any music. If they agree, please keep the volume low. Not everyone enjoys music while observing, so respect when you are politely told “No.” Also, consider playback that is pleasing to others. When in doubt, use headphones.


If you make a mess, clean it up. Help us keep LaGrange looking nice and presentable.  This facility is privately managed, and ultimately we are all guests who should not wear out our welcome.

Quiet Mornings

Observers may pull an all-nighter. Please respect the serenity of a morning with quiet.


Children are the future of amateur astronomy and we encourage parents to bring them along to the party. Observing can be a very exciting time for most everyone, kids included.

Please keep an eye on your children. No scope owner should endure an accidental (and fully preventable) destruction of an expensive instrument. Instruct children to never run or play near equipment — and especially never after twilight! Children should ask an owner’s permission before touching any equipment.

Observatory officials will issue only one warning if your child or children are breaking these rules. After that, you will be asked to leave the premises. Telescopes are investments, and damage can be prevented. We want to provide optimal circumstances for observing and that means keeping equipment free from harm.


Equipment is not the only thing that deserves consideration. At every opportunity, please provide respect to, and preserve the dignity of, all your fellow observers.


Do not touch a telescope without permission from its owner, and never touch the optical glass of a telescope or eyepiece. The oils on your skin can ruin the coatings.


If an observer brings a large telescope, a ladder may be required to observe. It may be a small stepladder, or a noticeable climb to reach the eyepiece. Please count steps as you ascend. If need be, ask the owner to count you down. It’s better to be safe than sorry. And whatever you do, DON’T BREAK YOUR FALL ON THE TELESCOPE!

Scope owners will not be held responsible if you are injured climbing their ladders. You will be held responsible for any damage you cause to a scope. By climbing the ladder, you assume the responsibility of getting up and down safely. If you’re unsure whether you can ascend and descend safely, don’t climb.


It’s fun to walk around the observing field during daylight hours, checking out all the scopes that are set up. You can see everything in great detail. But when walking a dark field, always use a red filtered flashlight, and keep it pointed toward the ground. Watch for power cords and tripod legs. Once your eyes become dark-adapted, it will be much easier to walk around the field.


Check weather forecasts before observing. Astronomy isn’t much fun if you’re not comfortable. Standing in night air can get quite cold, even in summertime. Bring layers and a cap. You can always shed layers.

Be Inquisitive. Have Fun!

If you’re concerned that your question sounds silly, don’t. Most of us asked the same questions when we began this hobby. Observing sessions are the best places to learn about the hobby. You will learn more in two days by asking questions and listening to discussions than you will in a year on your own.

The experience of celestial observation is indescribable. New friends will be made. You will look through a variety of different telescopes, and create a sense of fulfillment as you leave. Observers will often plan their next session while still observing in this session.

We hope you will enjoy observing with Shoals Astronomy Club at LaGrange College Historic Site. Questions, comments and concerns are welcome, so please let us know. We will try our best to make your visit an enjoyable one.

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