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The all-sky charts like in Sky and Telescope magazine can be confusing, so below is what I add to an all-sky chart if I am handing out copies to anyone.
Hope this is helpful.
- Dean
"Star charts are a bit confusing when you first use them! This is because they represent an entire hemisphere (1/2 the Universe!!), compressed into a tiny circle or oval, and they seem to have the East-West directions reversed.
You can get an idea of how they work by lying down, and holding the chart above you with North-South correctly oriented. You will notice that when you do this, East and West are also correct. The centre of the chart represents the zenith (straight up).
However, the easiest way (standing up) is to hold the chart vertically in front of you, with the direction you are facing at the bottom (twist the chart around).
E.g.: look for "Crux" (the Southern Cross) on the chart. Now face south with "South" at the bottom of the chart, at around the time given on the chart. You should see the Southern Cross in front of you.
Anything that is above the centre on the chart will be over your head and behind you: so just use the bottom 1/2 of the chart. As you turn to different directions, turn the chart as well so the direction you are looking is always at the bottom.
Because the earth moves around the sun in 12 months, every month the star chart is different for the same time of night (ie: we are looking out at a different angle to a different part of the universe). Eg: Orion is visible during the summer months in the evening, but as we head towards winter it gets closer to the sun, and eventually is only visible in the very early morning. "
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