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A lot of people join the Montreal Centre eager to go out and observe. But once under a dark sky, a lot of them are left wondering what they should be looking for and how they should go about finding it. Here's an observing project to help our members learn their way around the night sky and discover some of its hidden treasures with little more than a pair of binoculars.

Why binoculars? For one thing you can get a good pair of binoculars for a lot less than a telescope. In fact, some of you might already own a pair. If you don't and you would like to try before you buy, you can rent a pair from the center for a few dollars a week. Best of all, binoculars are light, portable and their wide field of view makes it a lot easier to move around the sky and find things without getting lost. What's more, with a star chart they'll get you used to star-hopping from one object to the next.

The Binocular Challenge consists of 40 objects spread out over the sky. You'll see that it's split into seasons and a map is provided to help you get started. However, given that the maps are rather small you may have an easier time finding some of the more elusive objects if you go out and obtain a set of star charts. Some of the objects are easy to find and some are a little more difficult. However, all of them are visible in a pair of 7x35 binoculars. In fact, a lot of them are naked-eye objects under a dark sky if you know where to look.

What you'll need BEFORE you go out

The first thing you'll need of course is a pair of binoculars. As I mentioned, all of these objects are visible in a pair of 7x35 binoculars. However, if you're planning on buying a pair of binoculars, I would suggest a pair of 10x50. Their greater light-gathering ability will make objects brighter and their higher magnification will enable you to see more detail.

The second thing I would recommend is a dim red flashlight to help you read your charts. I've found those with an adjustable l.e.d. not only last longer but can also be better adjusted so that the intensity doesn't affect your night vision.

Third, a good reclining lawn chair is a must. Not only will it enable you to lie back and avoid straining your neck, the elbow rests will help enable you to keep your arms steady.

Last of all, if it's cold, dress warmly. Try sandwiching yourself between a couple of sleeping bags, it really works! In the summer don't forget to bring bug repellent before the bugs decide to turn you into a late night snack.

Getting Started

Before you can use the accompanying charts, you'll first need to measure the field of view of your binoculars. Trust me, this sounds a lot more complicated than it really is.

Start by locating any bright constellation in the sky that you're familiar with, like the Big Dipper or Orion for example. Now scan it closely with your binoculars and find two bright stars that you can just fit inside the edges of the field. Next, locate those same two stars on your chart and make a mental note of their separation. Better yet, measure it with a ruler and then draw a circle of the same size on a clear piece of plastic. Now every time you'll move your binoculars one field in any given direction you'll have moved one diameter of your circle in the same direction on your star chart.

If you star-hop one field at a time like this you won't get lost. Also, you'll be able to count how many fields you have to move your binoculars to find any given object on your map. If you want you can also compare your measurement to the scale on the edge of the chart to get a rough idea of the field size of your binoculars in degrees. When I observed the objects on this list, I used a pair of 10x50 binoculars that have a 7 degree field. Or to put it another way, when I look at Orion I can just squeeze in both of his shoulders in the edges of the field.

Recording Your Observations

Once you've located what you're looking for you'll need to record your observations either in the space provided on the form or in a separate log-book if you need more room. This may sound straightforward but you may find it harder than you think to describe the little fuzzy patch you see in your binoculars. Especially if it looks a lot like the one you found a few minutes earlier.

One way around this is to make a drawing: start with the brighter stars first and slowly start filling in the fainter ones. If the field is crowded you can try one of Fr. Lucian Kemble's tricks. First, de-focus your binoculars slightly so that only the brighter stars are visible. Once you've drawn them, re-focus your binoculars and fill in the rest. Don't be afraid to experiment with different pencils. I like using a white Conté crayon on black cardboard, but it can be difficult to see what you're doing at times. Others prefer a 2B or HB lead pencil. If you need to add a little nebulosity try rubbing lightly with your finger or if you prefer you can use an artists blending stump. Although you may be disappointed with your first couple of drawings, if you keep at it you'll improve and more importantly you'll start to discern details that will escape most of your fellow observers.

If drawing is not for you and you're having difficulty finding the right words to describe what you see, try answering the following questions:

* What shape is it (round, oval) ?
* How big is it (how much of the field of view does it take up) ?
* How many stars can you see ?
* Do any recognizable patterns stand out (chains, circles, etc...) ?
* Are there any double stars ?
* What colours do you see ?
* Can you resolve most/some/any of the stars imbedded in it?
* How bright is it (how well does it stand out from the background sky)?
* How does it compare to a similar object you've observed?
* What does the rest of the field look like?

If you're having a little difficulty with a particular object don't be afraid to ask your fellow observers for a little help the next time you come to one of our outings or at the next Observer's Group meeting.

When you've observed all 40 objects on the list bring your descriptions to a board member and we'll prepare a certificate with your name on it. It is sure to make you the envy of all your fellow observers !

Clear Skies,
Marc Ricard

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