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On 3/20/2022 5:45 AM, David C wrote:
> Lat 41S
>
> Long 175° E
>
> An extra question is when will the equinox be at 0027 UT allowing me to
> take a noon sight at the equinix?

You can get pretty close on 2026 September 23, when the equinox occurs
at 00:06 UT1. At your local noon,

2026-09-23 12:00:00.00 LAT
2026-09-23 00:12:32.72 UT1
2026-09-23 00:13:42.96 TT

Sun topocentric apparent place
  49°00.02' unrefracted center altitude
   0°00.00' azimuth

Sun geocentric apparent place
180°00.27'  -0°00.12' equinox RA, dec
180°00.30'  -0°00.00' ecliptic true lon, lat


My solstice and equinox page has a table of the phenomena for the next
10 years. You can find that everywhere, but I also discuss related
matters. Any of four different angles could plausibly define a solstice
or equinox. Which is the formally correct angle to use? Difficulties
with the UT1 and UTC time scales. Why give long term predictions in TAI?
Attainable accuracy in predictions. Example calculation.

http://sofajpl.com/solstice/

I believe minor discrepancies in solstice and equinox times are usually
due to differences in computation of Earth orientation: precession,
nutation, and obliquity. The Sun ephemeris has less effect. At a
precision of one second of time, the late 1990s JPL DE406 gives results
virtually identical to recent ephemerides at epochs not far from the
present.

--
Paul Hirose
sofajpl.com

   

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