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    Re: 1901 May, 22 Lunar example by French Navy Captain Arago
    From: Antoine Couëtte
    Date: 2010 Jan 21, 23:56 -0800

    COMPLEMENTARY INFORMATION : The Moon Center height is laso quoted as being 53°24' (This forgotten data can be easily reconstructed)

    IN Navlist g11495 " cfuhb-acdgw---net " wrote :

    > One question though : are short limb distances still a limitation
    > nowadays with the powerful computation software available on line ?

    I have never tested my program with such an observation. If you have
    one, I'll try it.


    Sorry to reply quite late. My reply to-day will be just short (lack of time).

    In the quoted example (1901 May,22 Lunar example) F.N. Captain Arago gives an example of an occultation.

    Here are his data and results : (I have translated them into Greenwich time and Longitude).

    From position N48°23'30" W004°29'31.18" (Brest military harbourg) he observes an occultation of the star Khi Can by the Moon.

    Actually, given the star coordinates he uses, I rather think that this star nowadays is kappa Can (change of name in between ??? ). This star is listed as follows in the following star catalogs : BSC #3623 / FK5 # 1238 / SAO # 98378 / HD 78136. Its 2000.0 Mean elements are as follows : R.A.=09h07m44.819s *** µRA=-0.0014s/y *** Delta=N10°40'05.44" *** µDelta -0.01 "/y no parallax quoted.

    Here are the data Capt. Arago uses from CT :

    Moon equatorial Parallax : 55'33.1" , Moon SD 15'11.3" , Moon RA 9h01m45.58s , Moon Dec 11°14'05.4"

    For this position, and given the data he uses,he finds an occultation (immersion) time equal to 10h53m17.3s Paris time, which in to-day time reckoning is equal to 22h43m56.379S UT.

    That could be a starting point to check your own software.

    Time permitting I will dig out in my files an example of occultation of a "bright" body so that we can also check it on-line, with Frank's Software for example.

    Best Regards

    Antoine M. "Kermit" Couëtte
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