Uploaded image for project: 'Lucene - Core'
  1. Lucene - Core
  2. LUCENE-7158

Haversin should use the earth's mean radius, not its max (equitorial)?

    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 6.0, 6.1, 7.0
    • Component/s: None
    • Labels:
      None
    • Lucene Fields:
      New

      Description

      Across our spatial modules we seem to disagree about the earth's radius when we model it as a sphere.

      I think in our haversin implementation we use equitorial (maximum) radius, but maybe in spatial3d we use the earth's mean radius.

      I think mean makes more sense: the earth is actually a squashed sphere, so it's polar radius is shorter than its equitorial radius.

      I think it's important, when we model the earth as a sphere, that we pick one radius and try to use that one consistently?

        Attachments

        1. LUCENE-7158.patch
          14 kB
          Michael McCandless
        2. LUCENE-7158.patch
          17 kB
          Karl Wright

          Activity

            People

            • Assignee:
              Unassigned
              Reporter:
              mikemccand Michael McCandless
            • Votes:
              0 Vote for this issue
              Watchers:
              5 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: