2011 January 31 at 09:53 SAST

ConCards teach constellations and show best deep sky targets

Novice deep sky observers are faced with at least two challenges: learning the constellations, and finding the best deep sky views. A new set of charts, called "ConCards" (for 'constellation cards'), aims to help the beginner overcome these two hurdles.

The first goal of the ConCards are to help the beginner identify the constellations. Each Card shows a single constellation, illustrated by plotting the most prominent naked-eye stars it contains. Cues describing the prominence of the star pattern, and its period of visibility, help observers to decide when to explore a constellation.

A set of five finder charts helps the observer to orient each ConCard in the night sky. These finder charts take a slightly different approach to the usual: instead of trying to show as many stars as possible (causing clutter), the finder charts show only the brighter stars in the sky, as well as the emphasizing the official boundaries of each constellation.

To find a particular constellation, the observer would use the appropriate finder chart to locate the approximate position in the sky, and then note the orientation of the constellation's boundary lines. It is then a simple matter to turn and orient the detailed constellation chart so that the boundary lines match the orientation the finder chart shows.

The second goal of the ConCards is to highlight some of the cool deep sky objects in the sky. All to often, novice observers end up looking at the same objects again and again because they don't know about the other deep sky delights nearby. In Carina, for example, folk may turn to the gorgeous eta Carinae Nebula again and again, and not realize that a lovely globular cluster, NGC 2808, is just a stone's throw away.

The ConCards thus show a (subjective) selection of other highlights visible in the constellation being studied. Most of these objects can be picked up readily in binoculars, using basic star-hopping skills from the stars plotted on the Card. From time to time, however, the target object may not be a winner in binoculars, so a slightly more detailed map, for telescopic use, is shown.

The present version of the ConCards (pre-release, 0.53) shows all the constellations at least partially visible from mid-southern latitudes, so if you're a northern-hemisphere observer planning a trip to the south, these Cards are you "must see" list for southern gems.

The ConCards can be downloaded here:

ConCards (version 0.53, charts only)

Footnote: Another driver in the design of the ConCards was to assist the presenter/telescope operator during an outreach event by providing a summary of the basic data about each object plotted on the chart. I certainly can never remember how far the Jewel Box is, at what speed the Crab Nebula is expanding, or how old IC 2602 is.

In a future update of the ConCards, a compilation of this kind of information will appear on the reverse side of each Card, so that the present can use the Card as a finding aid, a suggestion of what to look at next, and as a reminder of the interesting factoids about each object. Collecting this information is taking a bit longer than I expected, so if you're keen to help, please get in touch!

ConCards (version 0.53)