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Coordinates menu, under the Go To menu. The Coordinates menu also has an "Opposition Point" option, to find the point directly opposite the sun. When entering an alt/az position, you will be asked to enter the altitude first. This can range from -90 (straight down, the "nadir") to zero (a point on the horizon) to 90 (straight up, the zenith). Next, you will be asked to enter an azimuth, or "bearing". This can range from zero (due north) to 90 (due east) to 180 (south) to 270 (west) to 360 (north again). Guide will then recenter on the position given. A description of alt/az is given in the Appendices, on page 75. If the coordinates aren't being shown in the Legend, you can toggle them on quite easily. This is described on page 24. A comment on entering RA/dec positions. Guide is quite willing to accept the many forms of RA/dec coordinates; for example, 10h42m36.00s N41.69 10h 42m 36s N41 41' 24" 10 42 36 +41 41 24 10h 42.6m N41 41.6' 10.71h +41 41' 24" all refer to the same position in the sky, and all will be correctly understood by Guide. You can leave out minutes or seconds, put spaces between fields, use +/- in place of N/S, and use decimal amounts. If Guide can't figure out what you meant, it will tell you so with an error message, and will give you a chance to try again. If you want to reset the format or epoch Guide uses for showing RA/dec values, use the "RA/dec Format" option described on page 30. There will be edit boxes for the RA and declination, plus one for the epoch. The default value for this is J2000.0. "Epoch J2000.0" tells you that, by default, all positions are shown and are expected to be entered in the J2000.0 epoch. (The "epoch" is explained in the Appendices, page 73.) This epoch is used throughout Guide. Not only is it the epoch used when you enter a position; it is also the epoch in which your current position is shown, and in which all positions are shown in ephemeris and "more info" data. (There are a few exceptions to this in the "more info" section. They are all given labels such as "J2000", "B1950", "coordinates of date", and so forth, so that you can clearly distinguish them.) For your own purposes it is not likely that you will disturb this, because J2000 is in almost universal use today. But in older literature and many catalogs, the position of an object is often given in B1950 (or other) coordinates. Before entering such
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