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Halley's lunars, back in 1698-1700 (corrected)

From: George Huxtable (no email)
Date: Wed May 05 2004 - 14:34:23 EDT

  • Next message: Rodney Myrvaagnes: "Re: Halley's lunars, back in 1698-1700"

    Sorry to say that I've detected a couple of careless errors in my posting
    about Halley's lunars earlier today. So I had better correct them before
    someone else does. There may of course by further errors, as yet
    undiscovered.

    In the first paragraph was a mention of-

    "his two voyages around the Atlantic, in the British Navy 89-ton pink
    "Paramore", as early as 1698-69 and 1699-70." The date of the first voyage
    should, of course, have been 1698-99, not 1698-69.

    After quoting a passage from Halley's log, I added-

    "Note that Halley makes a step-change in his presumed long. at noon, from
    his DR value of W 31deg 13' to a new value, based on his lunar, of W 36deg
    35', a change of 5deg 20' or nearly 500 miles!

    That change in longitude should have been 5deg 22', not 5deg 20', which
    corresponds to 300 miles, not "nearly 500 miles".

    Sorry about that,

    George.

    ================================================================
    contact George Huxtable by email at , by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ================================================================


  • Next message: Rodney Myrvaagnes: "Re: Halley's lunars, back in 1698-1700"



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