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- Cut out the two central circles of stars.
- Paste the two circles together, back to back, keeping the months aligned.
- Study for a moment how the SHA labels correspond to the right ascension labels in the pictures below. (Sidereal Hour Angle is the angular distance of a star west of Aries on the star globe. Right Ascension is the hourly distance of a star east of Aries. Navigators use the former, astronomers the latter. See discussion in the Star Finder Book.)
- Put one of the yellow stickers (provided) over each of the right ascension hour labels as shown and label each side of the map with the SHA.
- Optional: have the map then laminated or cover it with clear contact paper. (This is optional as it will likely last just about as long without this extra protection, and it folds better without it.)
section of the map showing SHA labels
Below is what the corresponding map section looks like in the Nautical Almanac maps.
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