Talk:Analemmatic sundial

Latest comment: 12 years ago by Johnmahorney in topic reliable sources

Possible sources for expansion

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reliable sources

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Reference number 2 is not a reliable source.

It is a link to "Sunclocks - Human Sundials, using your own shadow to tell correct time" which is a commercial web site that sells sundial designs.

Johnmahorney (talk) 19:23, 22 August 2012 (UTC)Reply

incorrect statement

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This article has an incorrect statement:

"Accurate dials of this type are popular in public places, using a ball at the tip of a flagpole as the nodus, with the sundial face painted on or inlaid in the pavement."

Analemmatic sundials have a movable gnomon - therefore a fixed flagpole cannot be used as the gnomon.

Johnmahorney (talk) 18:58, 22 August 2012 (UTC)Reply


Confusion of definitions

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This article confuses two separate concepts:

  • An analemmatic sundial, in which a shadow of a vertical gnomon falls on hour markers placed on an ellipse. The position of the vertical gnomon changes during the year according to the sun's declination.
  • A sundial in which a ray of the sun, or a shadow point of the sun, falls on an analemma marked on a dial or other surface.

These are two different things, and the article needs to be improved to clearly distinguish between them.

Cmcqueen1975 (talk) 03:16, 15 June 2010 (UTC)Reply