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I read that there is less atmospheric interference for the telescope at the South Pole because the atmosphere is thin and there is less water vapor in the air. However this seems to be true for many locations on Antarctica? Are there any other reasons that this telescope is located at exactly the South Pole?

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    $\begingroup$ Because you need a supporting infrastructure, and there is already a scientific base at the south pole. $\endgroup$ – Rob Jeffries Apr 17 '17 at 16:46
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    $\begingroup$ ps. I have used (remotely) a telescope at the south pole, so this is hardly a new idea. arcticphoto.co.uk/gallery2/antarctic/antpeople/antscience/… $\endgroup$ – Rob Jeffries Apr 17 '17 at 16:51
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    $\begingroup$ It's also not quite exact. The ice moves by some amount (tens of meters per year, I think), and they're on the ice. I don't know if they can move the telescope, but I doubt that they do. $\endgroup$ – Sean E. Lake Apr 17 '17 at 16:52
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    $\begingroup$ ...well, when they tried to locate the South Pole Telescope at the North pole, everyone got confused... $\endgroup$ – HopelessN00b Apr 17 '17 at 21:07
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    $\begingroup$ @RobJeffries wow.... $\endgroup$ – Anubhav Goel Apr 18 '17 at 1:33
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Here are extra reasons to the dry air :

During the winter, sunshine does not reach the South Pole; nighttime (or daytime in the summer) extends for months. The lack of daily sunsets and sunrises makes the atmosphere extremely stable. Conducting observations in the winter also removes another contaminant to millimeter/sub-millimeter observations - the sun. All these factors conspire to make the South Pole the perfect place for the South Pole Telescope.

The further north these extra reasons for choosing the South Pole plateau become important, there will be increasing presence of the sun.

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    $\begingroup$ I think, on symmetry grounds, that the pole must be the place that maximises the continuously-dark (and similarly continuously-light in fact) intervals, so this smells like a good reason to me. $\endgroup$ – tfb Apr 17 '17 at 21:58
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    $\begingroup$ I disagree - the reasons are much more likely logistical, as described by dmckee. If the Amundsen-Scott station was at 85° S, you can bet that the 'scope would have gone there as well. The station was installed at the pole back in 1956, when none of this was a consideration; putting it at the pole was exclusively about bragging rights at the height of Cold-War competitiveness. $\endgroup$ – Emilio Pisanty Apr 18 '17 at 8:56
  • $\begingroup$ @EmilioPisanty They did have a choice between one of the coastal stations, which would have been easier on the personnel, or the one on the pole, after all. These are the reasons they give for choosing the pole. They would have been better supplied on the coast after all. $\endgroup$ – anna v Apr 18 '17 at 9:09
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    $\begingroup$ @annav Those are reasons to choose the central plateau. The question asks why the telescope is precisely at the pole itself. $\endgroup$ – Emilio Pisanty Apr 18 '17 at 10:00
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Just guessing here, but ...

Compare the regions with really good skies with the places that have infrastructure and people present. Most of the installations are coastal, right? Are those good places to put a telescope? And while the whole inland plateau has good skies, it has few occupied site, and only one operated by the US.

So what is the case for putting up some other (very expensive to build and maintain) installation, when you could just drop it by South Pole Station where they already maintain a year-round presence.

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    $\begingroup$ That then brings up the question of why the station was set up precisely at the pole, if it wasn't for astronomic reasons. But then again, if you just need to set up shop somewhere within a featureless plain of ice and any spot is as good as any other, you might as well go for the spot with the most cred, I guess. $\endgroup$ – Emilio Pisanty Apr 17 '17 at 17:02
  • $\begingroup$ @EmilioPisanty the name "South Pole Region Telescope" would be severely unwerwhelming, indeed. $\endgroup$ – Kroltan Apr 17 '17 at 18:22
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    $\begingroup$ @EmilioPisanty: The Amundsen-Scott Station was built back in the mid-50s as part of the International Geophysical Year (which had a particular focus on the Antarctic); astronomy wasn't a big concern until the early '90s. There does appear to have been a bit of East/West competition for the bragging rights as well; see this article. $\endgroup$ – Michael Seifert Apr 17 '17 at 18:27
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    $\begingroup$ There's a number of research bases in Antarctica, and more than just the Amundsen-Scott station are "inland". However, Amundsen-Scott is the only US station which is inland, which may be a consideration for a (US) NSF-funded telescope. $\endgroup$ – R.M. Apr 17 '17 at 19:13
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If the telescope was situated directly on the southern axis of the earth's rotation, the telescope's declination axis would be at zenith. The base for the axis would be level to the ground. In theory you could compensate for the earth's rotation with only one motion of the telescope. Also, its the only place on earth where the entire southern celestial hemisphere is visible. Now, are these the reasons it is built there, probably not but they would be advantages.

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protected by Qmechanic Apr 17 '17 at 20:32

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