![]() Different star paths are also used when there are strong currents GLOSSARY currents - the directional flow of the sea or winds Six months later, the same stars are only above the horizon in the day and so can’t be seen. ![]() Any star path can only be used in a particular season. A journey between two islands can have more than one star path. Often, songs or stories are used to remember the star paths GLOSSARY star paths - the sequence of stars to follow from one island to another. There might be up to 10 stars in a star path for one night’s sailing, but only one might have a name. A wayfinder then uses the next star that rises in the same direction, and so on. It moves to the side of the island and soon is no longer a good guide. A rising star, however, doesn’t go straight up from the horizon GLOSSARY horizon - the line where the earth and sky seem to meet (unless you are at the equator). A wayfinder steers towards the star that rises or sets in the direction of the destination island. Some stars are always up and others always down (similar to the situation at the Poles), some are up and down half the time (similar to the situation at the Equator), and others are up more than half the time but not all the time, and others are down more than half the time but not all the time.įor every part of the sky where stars are up more than half the time, there is a symmetrical part where the stars are up less than half the time, so that on the average half of the sky is up at any given time (which should go without saying :-) ).A star that is just rising or setting is a very good guide. Every star is up half the ‘day’ (24-hr on the Earth), and down half the ‘day’.Īt mid-latitudes (such as where we live), things are more complicated. Therefore, at the poles of the planet the Celestial Pole is overhead at the Equator it is on the horizon and at mid-latitudes it is at an angle to the horizon.Īt the Pole(s) the paths of the stars are horizontal, never getting any higher or lower (for a given star), so that if a star is up it is always up, and if it is down it is always down.Īt the Equator the paths of the stars are vertical, are cut exactly in half by the ‘horizon’, and since the motions of the stars are ‘uniform’, each and every star is up half the time and down half the time. The altitude of the Celestial Pole (its height above the horizon) is the same as your latitude. Whatever angle a star rises North or South of East, it sets at that same angle North or South of West. The closer a star is to the Celestial Equator the more nearly it is up half the time and down half the time the closer it is to a Pole, the more nearly it is always up or always down. ![]() Stars following paths 'B' and 'C' are up more than half the time, while stars following paths 'b' and 'c' are down more than half the time. ![]() Stars following path 'a' are always down, even though they get higher and lower, because they are closer to the South Celestial Pole than it is to the Horizon. Stars following path 'A' are always up, even though they get higher and lower, because they are closer to the North Celestial Pole than it is to the Horizon. Half the Celestial Equator is above the Horizon and half is below it, so stars on the Celestial Equator are up half the time, and down half the time, just as at the Equator (where all stars are up half the time, and down half the time). The Celestial Equator rises at the East point at a 35 degree angle to the vertical, crosses the Meridian (the North-South line through the Zenith) 35 degrees south of the Zenith and sets at the West point, at a 35 degree angle to the vertical. The South Celestial Pole is 35 degrees below the South point on the horizon. The North Celestial Pole is 35 degrees above the North point on the horizon. The stars move parallel to each other and the Celestial Equator. ![]()
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