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Re: Lunars at Cusco, Peru
From: Paul Hirose
Date: 2024 Jun 14, 10:49 -0700
From: Paul Hirose
Date: 2024 Jun 14, 10:49 -0700
> *From: *Martin Caminos
> *Date: *2024 Jun 13, 10:55 -0700
>
> In my case, the day of the sight, the pressure at Cusco (that I checked
> online) was 688 and the temperature was 12 C.
But pressure is 668 in your screen shot. That's very close to the 3400 m
pressure in a standard atmosphere (666 mb). What was the correct pressure?
> With that, I calculated the following refraction corrections:
>
> Regulus: -0.45 '
>
> Moon: -1.29 '
Azimuths are almost identical, so the refraction correction to lunar
distance is almost the difference of the altitude refractions.
2024-06-10 00:03:50.00 UTC
2024-06-10 00:03:50.00 UT1
2024-06-10 00:04:59.20 TT
-71°55.00' -13°31.40' east lon, north lat
3400.0 meters (11155 feet) above ellipsoid
12.0 C (53.6 F) at observer
1013.3 mb (29.92″ Hg) altimeter setting
666.3 mb (19.68″ Hg) air pressure
Moon
17°46.67' computed unrefracted center altitude
-15.31' unrefracted semidiameter
1.98' refraction
17°33.34' apparent lower limb altitude
301°49.68' predicted azimuth
Regulus
46°37.90' computed unrefracted center altitude
0.60' refraction
46°38.50' apparent center altitude
304°12.32' predicted azimuth
topocentric apparent Moon to Regulus angle
28°55.24' center to center, unrefracted
1.35' refraction
28°53.89' center to center, refracted
15.28' Moon far limb refracted SD
29°10.00' observed angle
29°09.17' computed Moon to Regulus
+0.83' observed - computed
--
Paul Hirose
sofajpl.com
