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If we look at the Sun from where it appears in the morning —roughly in the east— we will see that it rises during the morning until reaching its maximum height with the horizon, which we opportunely call midday since as many hours of daylight have passed as those that remain until sunset.
As the afternoon progresses, it descends until reaching the horizon —roughly in the west— and at the end of the day its trajectory has drawn an arc. If we look at the sky late at night and note the position of the brightest stars, we will see that after a few hours they make the same movement as the Sun: some stars will set in the west, other new ones will rise in the east, and all the stars of the firmament will move following this pattern.
All of them? No, all except one: Polaris. Imagine a bicycle wheel, a record player with an old LP or any disc that spins. The trick is to place your finger on the axis of rotation; the speed in the centre is zero and as we move the finger away from the centre the linear speed increases as the radius of rotation increases.
If we locate this star and note its position, we can come back in a few hours, days, or years and we will always find it in the same place. The other stars vary their position and will most likely be in other parts of the sky, but Polaris will not have moved.
The only way to see Polaris move from its spot is to travel. If we head south, the further south we go the lower it will appear —closer to the horizon— until we reach the equator, at which point it will be flush with the horizon. When we travel northward, the opposite happens, and the star rises in the sky. At the North Pole a singular event occurs: the Pole Star is seen right at the highest point in the sky, the zenith, hence its name. It is the star that is located in the centre of the sky.
Asked 5 years, 4 months ago. Active 24 days ago. Viewed 25k times. Improve this question. Add a comment. Active Oldest Votes. Improve this answer. David Hammen David Hammen Which is almost 3 degrees South. The earth's atmosphere also diffracts in another degree or two and if you climb a mountain, you get another degree or three that way, so you can probably see over degrees of the night sky from the south pole at some point in the year. Axial tilt is not a factor over the course of a year.
Over thousands course of hundreds of years, yes, but over a year it's very small. From the south pole you can see half the sky. That makes sense now that you've pointed it out. SE - stop firing the good guys 4, 13 13 silver badges 35 35 bronze badges. James Screech James Screech 1, 6 6 silver badges 15 15 bronze badges. Sign up or log in Sign up using Google.
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