There is a North polar star, is there a South polar star?
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answers:
Athena say: Nope, not really.
In fact the North polar star is just the current one and not anything special. 2000 years ago there was a different star within the north celestial axis. 2000 years from now Polaris will no longer be the "North Star. "
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goring say: At one time the scientists believed the Earth was a circular Disk with a certain thickness.Hence two types of people the opposite of the disk was the Anti Podients which saw the Southern Cross.The others saw the Polaris which did not appear to change position on the celestial sphere ,and was used for navigation.
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Clive say: No. It's also only coincidence that there is a North Pole Star that is easy to see.
It won't be the Pole Star forever, either. The Earth precesses with a period of about 26,000 years - that is to say, it has a very slow wobble, like a spinning top wobbles round and round as it slows down. (Just as well there is the Moon - the gravity of our unusually big Moon helps stop it wobbling more than it does! All good for life on Earth - it keeps the climate stable.) One effect of this is to make the North Pole trace out a circle in the sky over 26,000 years, so it won't always be pointing at Polaris. If you were around when the Egyptian pyramids were being built, there wouldn't have been an obvious pole star. So it's only being around here and now in 2019 that could even lead you to ask the question.
Just for fun, this is evidence that astrology is complete crap. "Western" astrologers ignore the real sky, ignore precession, and are still using planet positions where they would have been 2,000 years ago - when nobody knew about precession. And another effect of precession is to make what constellation the Sun is in at any particular time move round, going right round the zodiac every 26,000 years, so by now they're about one constellation out.
We just got lucky, really, that as civilisations developed and started sailing the world, there WAS a handy Pole Star sailors could use to navigate with.
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Tom say: by coincidence, Polaris seems to line up pretty well much with the north polar axis.---So we call it "The North Star" Not particularly bright either. Unfortunately, no visible stars line up with the South polar axis, so there is NO "South star" The universe doesn't even think about little old Earth down here and could care less.
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Ronald 7 say: There is a Circumpolar Constellation called Octanis
Named as such by Seafarers for resembling an Octant
Like many other Southern Hemisphere Constellations, they had not really been mapped until World Sea trade had taken off
Northern ones had been known since Antiquity
Anyway, there is a faint, distant Star called Sigma Octanis that lies right at the Southern Celestial Pole
It was picked out in the Dark Winter Skies of the Southern Ocean
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Raymond say: Certainly not in the same context. There is a very faint star (Sigma octantis) that is too faint to be used in navigation (by the time it becomes visible, the horizon has disappeared).
Navigators need (or needed, back before the invention of GPS) to see both the horizon and the star through the small 3x telescope of the sextant. In the old days, they used a quadrant that had no telescope at all. The idea is to measure the angle between the star and the horizon (to find your latitude) and to point a compass to a point on the horizon directly below the pole star (to determine the compass error). This must be done during Nautical Twilight (the sky is still bright enough to make the horizon visible, yet dark enough for some stars to be visible).
In the North, you can use various "pointers" to help you find Polaris (the "Pole Star") -- it is barely bright enough to be found during Nautical Twilight... if you know where to look. The two bright stars at the pouring end of the Big Dipper are the best known pointers (there are others). You take the distance between them, multiply it by 5 (or a bit more) and measure that off along the line joining these two stars.
In the South, the most popular pointer is the Southern Cross. The long axis of the cross points directly south, and the pole is 4-and-a-half times the distance away. However, there is nothing there that is useful during Nautical Twilight. By the time Sigma Octantis becomes visible, everything around you is pitch black; no horizon.
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nineteenthly say: Kind of. Sigma Octantis, but it's quite faint and "off-centre" compared to Polaris.
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tham153 say: There is nothing brighter than fifth magnitude near the south celestial pole, which falls in the rather dim constellation of Octans
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YKhan say: No, but there is a constellation of 4 stars that form a cross through the southern pole, called the Southern Cross.
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JetDoc say: No.
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Athena say: Nope, not really.
In fact the North polar star is just the current one and not anything special. 2000 years ago there was a different star within the north celestial axis. 2000 years from now Polaris will no longer be the "North Star. "
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The_Doc_Man say: The star Polaris is the current "North Star" but the wobble of the Earth on its axis means that in a few thousand years the honor will belong to Vega.
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vikas say: No... never...
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Vaman say: There is no south pole star. Therefore, sea travelers were finding it difficult to travel. Often they missed the destinations.
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Lizzie say: No. I don't think so.
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TedEx say: https://www.space.com/29445-southern-cro...
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Tom S say: Not currently a very bright one, no.
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Jim say: There is, but it is very faint.
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MARK say: Yes, there is a southern pole star. It is called Sigma Octantis. Unlike Polaris (the northern pole star) it is not suitable for navigation. Its apparent magnitude is 5.45 and can barely be seen on a clear night.
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Iridflare say: No! In fact this was a problem for theists when European sailors first explored the southern hemisphere - how could God have neglected to provide a southern polar star to help them?
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quantumclaustrophobe say: Not really... there's a dim star very close, but it's not anywhere near as bright (or as centered) as Polaris is over the north pole.
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Athena say: Nope, not really.
In fact the North polar star is just the current one and not anything special. 2000 years ago there was a different star within the north celestial axis. 2000 years from now Polaris will no longer be the "North Star. "
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oneofmagi@rocketmail.com say: In earth only.
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say: Southern Cross
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Funnelweb say: As others have said, the star Polaris Australis (Sigma Octans) is the closest visible star to the celestial south pole. It is very faint (apparent magnitude ~ 5.5) and at a declination of 88.57° it isn't quite as close to the south pole as Polaris is to the north pole.
Australian naked eye astronomers can use the Southern Cross and Alpha and Beta Centauri to locate the south pole, and all these stars are readily visible even in the Australian cities. The method:
- imagine a line connecting Alpha Centauria and Beta Centauri;
- imagine a perpendicular line bisecting the line described above: this perpendicular line goes through the south pole;
- then follow the line of the long axis of the Southern Cross: this line also goes through the south pole;
- so the intersection of these two lines is the south pole (or very close indeed to it).
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crion87 say: No.
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poldi2 say: There is no star near to the south celestial pole, the closest is Sigma Octantis but its not very bright and not very close.
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