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Tweefo
2006-Sep-24, 06:08 PM
How did the first people to reach the poles new they were there and not a few meters or kilometers from it? They had no GPS's and a magnetic compass would be useless that close to the pole. It was day time so the stars was out. Something to do with the sun but that precise?

Ronald Brak
2006-Sep-24, 06:59 PM
They stood there for a long time and checked if the sun remained the same distance from the horizon.

astromark
2006-Sep-24, 07:29 PM
" They looked for the barbers pole" That red and white pole with the stripes.
They asked a Penguin, or polar bear.
Used Google Earth,
followed a map.

None of the above.
Used direct observation of star trails above pole.
and the winner is... By tracking the suns path.

GOURDHEAD
2006-Sep-24, 07:31 PM
Knowing that they had reached the pole is trivial compared to knowing where their destination is for those who wish to use wormholes to navigate the universe.

grant hutchison
2006-Sep-24, 08:21 PM
If you know the date, you know how high the sun should be above the horizon at any given time when seen from the pole, so you don't need to hang around for a long time to check that the sun's elevation doesn't change.
At the south pole, Amundsen did stayed in the vicinity for more than a day, which allowed careful checking of his location, but also allowed him to compensate for the irreducible error in his sextants and clocks. He sent out skiers in four directions to make sure that his polar team circled the entire error box for his location.

Grant Hutchison

01101001
2006-Sep-24, 08:22 PM
How did the first people to reach the poles new they were there and not a few meters or kilometers from it?

What was it that led you to believe they knew they were there?

Straight Dope: Who was the first to reach the north pole? (http://www.straightdope.com/columns/060609.html)


Explorer Sir Wally Herbert estimates Peary never got closer to the pole than 30 to 60 miles. A 1990 National Geographic article, on the other hand, places him within five miles (his instruments' margin of error) based on analysis of his photos and depth soundings. NatGeo's photo evidence is questionable, but the soundings show Peary headed roughly the right way. The celestial observations he made near his last camp are correct; for confirmation, he marched five to seven miles in all directions and made more sightings. Even if he was off initially, surely at some point during these peregrinations he got pretty close.

Wikipedia: Robert Peary (http://en.wikipedia.org/wiki/Robert_E._Peary)

Controversy


Some polar historians believe that Peary honestly thought he had reached the pole. Others have suggested that he was guilty of deliberately exaggerating his accomplishments. Still others have suggested that any hint that Peary did not reach the pole must be the work of pro-Cook conspirators who are simply out to discredit Peary. In 1989, the National Geographic Society concluded based on the shadows in photographs and ocean depth measures taken by Peary that he was no more than five miles away from the pole.

Ken G
2006-Sep-24, 08:24 PM
Interesting. And given the size of Amundsen's error box, it seems likely that no one in his party was ever actually at the South pole. Still, close enough is close enough.

(added in edit: and the north pole business suggests that just what is "close enough" is itself controversial!)