Observing Tips

Planning

Planning can enhance the success of an observing session immeasurably. It begins indoors in good light. The planisphere (pictured right) provides a year-round 24-hour map of the sky. A window opens onto the part of the sky visible for the time of year and time of night. Use it to survey the possibilities. Objects set in the west, so you would often make a west to east plan to catch those objects for which there is less time. 

 

The window at the right is for late February about 8 pm. The North Star is at the brass rivet. The south edge is up. You hold the planisphere overhead, and whichever way you face, make that be the forward edge. Orion is near the south edge. You see Big Dipper rising bucket first in the northeast.

Select a site away from outdoor lighting if possible. Align your finder scope which is a small scope that rides on the larger scope’s tube. Be precise about sighting and centering a distant treetop or other object, first in your scope and then in the finder. At night if you center an object in the finder, that object should appear somewhere in the scope’s field of view.
 

planisphere.jpg

Have a table near the scope to set things on. Make a recipe for how you will use the sky neighborhood to find your object, making a trail from one star to the next. A red light helps to read charts and preserve night vision (more below). Red plastic covering an ordinary flashlight will work.

Solar Observing – Caution

 

Use an approved filter. Permanent eye damage can result from looking directly at the Sun, especially if the light is magnified. It is also not safe to view a partial eclipse directly. A reflector telescope, with its internal reflections could be destroyed. Reflectors must have an astronomical solar filter – don’t try to rig something. Refractor telescopes (with lenses, not mirrors) can be pointed at the Sun and will project an image at the back onto white paper. 

 

Lunar Observing

 

The moon’s brightness can cause much eye strain. Neutral density and dark color filters for telescopes help solve this problem. If you are using binoculars, plan to take frequents breaks from the Moon. 

Dressing. Observing burns calories but creates little heat. You should dress as if it is 20 degrees colder than the forecast temperature, and be sure to factor in wind chill. For cold nights, a ski mask and ski pants might be called for. Heavy socks will help, as well as scraps of old carpet on the ground where you will stand. A deck chair or a hammock and a sleeping bag can add warmth and reduce neck strain. You do not want to be cold, hungry, tired, or tense when trying to find faint objects. 

Telescope Cleaning. It’s best not to. If it’s necessary, swab with camelhair brush and household alcohol. Don’t rub.

 

Location

 

Atmospheric conditions can greatly affect your limiting magnitude – the dimmest objects you can see. Getting even three blocks away from the center of town can bring a comet into view. Rural sites are naturally the best – pun intended – but local lights such as road traffic and streetlights, because they are nearer, can be even more of a problem. Find a spot where tree trunks and branches block light. Create a shadowy site by using old cloths or blankets for screening. 

 

Consider portability when making site plans. You will not want to reposition a telescope, so find an open area or limit your goals. Binoculars and a deck chair rate high in portability. 

 

Technique

 

As with the weather in general, there is no controlling sky conditions at night. Partly cloudy can mean a sky mostly indiscernible to a beginner. Perfectly clear skies can be problematic: if the day has been warm, convection currents can make your seeing wobbly. 

 

Get the big picture first. Use your eyes to spot binocular candidates. Use binoculars to find telescope candidates. 
Be patient while you develop your night vision which can take up to 20 minutes. Keep one or both eyes closed if white light should enter your view. If an object seems to peek at you and then hide, try using averted vision. Look slightly to one side of the suspected location.

 

Give Back

 

Invite the neighbors and especially any children to have a look. They want to know what you’re up to out there. Host a party for events like eclipses and comets. Invite others to bring their equipment and share stories.

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