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TQL: Navigating with Scorpius

Navigating with Scorpius 

(The "Today QiYun Learnt" Digest: Celestial Navigation Series)


On the way back from my run, I stared into the night sky and saw a couple of stars that looked like Orion's Belt (belonging to the constellation Orion) at first, but found that it was a bit dim. So I used the app Sky Map to search it up, and found that it was Scorpius, and what I saw was Scorpius' tail, not Orion's belt. In fact, Orion and Scorpius will never appear in the night sky together as they are opposite sides of the sun. As the myth goes, Scorpius will eternally chase Orion around the Earth but will never catch him. In the Summer night sky, in the Northern Hemisphere, you will see Scorpius, and in Winter, you will see Orion. 

I searched it up a bit more and today I learnt how to use the Scorpius constellation to navigate and find one's direction. 
Finding South with Scorpius
To find South, there are two conditions/scenarios to consider:

1. When the head is more or less vertical with the horizon: find south by way of an imaginary straight line from Scorpius' head (marked by the star Antares), to the kink in Scorpius' tail (where the tail suddenly kinks and changes direction from its original gentle curve), and then down to the horizon. 

2. When the tail is more or less vertical with the horizon, find south by way of an imaginary line drawn as straight as possible through the head (marked by the star Antares), and down to the horizon.

These imaginary lines may not intersect with the horizon at exactly due south, buy they'll be plenty close enough to help you find your way to a lengthy baseline.


Scorpius is located at a latitude of 26 degrees South, so when you are at that latitude, Antares passes straight overhead. My guess is that this is useful for determining your position when using a sextant be it a proper one or a makeshift one.



As for Orion, that's a story for another time. Orion has a story of his own, and he is plenty helpful in celestial navigation, especially near the equator in the northern hemisphere, where Polaris (the North Star) may not always be clearly visible.



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