Full moon reported an improper time

Hi guys,

this looks like it may be related to issue 33? I assumed that dateutil understands proper ISO / RFC3339 dates, since https://pypi.org/project/python-dateutil/ claims "Parsing of RFC strings is supported as well". So I guess the proper UTC time arrives at the code.

```
$ pyphoon 2023-08-01T18:31:34Z # actually the super full moon of August 1st (according to timeanddate.com).
.------------.
.--' o . . `--.
.-' . O . . `-.
.-'@ @@@@@@@ . @@@@@ `-.
/@@@ @@@@@@@@@@@ @@@@@@@ . \
./ o @@@@@@@@@@@ @@@@@@@ . \.
/@@ o @@@@@@@@@@@. @@@@@@@ O \
/@@@@ . @@@@@@@o @@@@@@@@@@ @@@ \
|@@@@@ . @@@@@@@@@@@@@ o @@@@|
/@@@@@ O `.-./ . @@@@@@@@@@@@ @@ \ First Quarter +
| @@@@ --`-' o @@@@@@@@ @@@@ | 6 19:23:21
|@ @@@ ` o . @@ . @@@@@@@ | Full Moon -
| @@ @ .-. @@@ @@@@@@@ | 0 1:01:52
\ . @ @@@ `-' . @@@@ @@@@ o /
| @@ @@@@@ . @@ . |
\ @@@@ @\@@ / . O . o . /
\ o @@ \ \ / . . /
`\ . .\.-.___ . . .-. /'
\ `-' `-' /
`-. o / | o O . .-'
`-. / . . .-'
`--. . .--'
`------------'
```
Applying the delta, I get ;-)
```
$ pyphoon 2023-08-01T19:33:27Z # not a full moon in the sky, but sure a beauty in the console
.------------.
.--' o . . `--.
.-' . O . . `-.
.-'@ @@@@@@@ . @@@@@ `-.
/@@@ @@@@@@@@@@@ @@@@@@@ . \
./ o @@@@@@@@@@@ @@@@@@@ . \.
/@@ o @@@@@@@@@@@. @@@@@@@ O \
/@@@@ . @@@@@@@o @@@@@@@@@@ @@@ \
|@@@@@ . @@@@@@@@@@@@@ o @@@@|
/@@@@@ O `.-./ . @@@@@@@@@@@@ @@ \ Full Moon +
| @@@@ --`-' o @@@@@@@@ @@@@ | 0 0:00:00
|@ @@@ ` o . @@ . @@@@@@@ | Last Quarter -
| @@ @ .-. @@@ @@@@@@@ | 6 15:56:29
\ . @ @@@ `-' . @@@@ @@@@ o /
| @@ @@@@@ . @@ . |
\ @@@@ @\@@ / . O . o . /
\ o @@ \ \ / . . /
`\ . .\.-.___ . . .-. /'
\ `-' `-' /
`-. o / | o O . .-'
`-. / . . .-'
`--. . .--'
`------------'
```
Do you have have a phoon/phoon-c version handy to see if this difference was in there, too?

### Ephem / XEphem / PyEphem comparison

Apparently [ephem](https://www.clearskyinstitute.com/ephem/) by [Elwood Charles Downey](http://www.clearskyinstitute.com/resumes/ecdowney/resume.html) on which [XEphem](http://www.clearskyinstitute.com/xephem/), ([nowadays](https://xephem.github.io/XEphem/Site/xephem.html)) and [PyEphem](https://rhodesmill.org/pyephem/tutorial.html) was based, produces output that looks suspiciously similar to pyphoon's (some whitespace omitted):
```
Select: Sky dome, Alt/az sky, Solar system, Earth, Moon, No trails
CET 20:31:34 8/01/2023
LST 11:59:16
.--------------.
.----' o . `----.
.-' . O . . `-.
.-' @@@@@@ . `-.
.'@ @@@@@@@@@@@ @@@@@@@@ . `.
.'@@ @@@@@@@@@@@@@@ @@@@@@@@@@ `.
.'@@@ o @@@@@@@@@@@@@@ @@@@@@@@@@ o `.
/@@@ @@@@@@@@@@@@@@ @ @@@@@@@@@@ @@ . \
/ @@@@@@@@@@@ . @@ @@@@@@@@@@@@ @@ \
/@ o . @@@@@@ o @ @@@@@@@@@@@@@@ o @@@@ \
/@@@ . @@@@@@@@@@@@@@@ @@@@@ \
/@@@@@ @ . @@@@@@@@@@@@@@ @@@ \
|@@@@@ o `.-./ . @@@@@@@@@@@@ @@@ . |
/ @@@@@ __`-' o @@ . @@@@@@ \
|@ @@@@ . @ ` @ @@ . @@@@@@ | First Quarter +
| @@ @ o @@@ o @@@@@@. | 6 20:23:21
| @ @@@@@ @@@ | Full Moon -
| . . @ @ @ o @@@@@ . . | 0 0:01:52
\ @ .-. . @@@ . . /
| @ @ @ @ `-' . /
\ . @ @ . o /
\ o @@@@ . . /
\ @@@ @@@@@@ . o /
\ @@@@@ @@\@@ / o . /
\ o @@@ \ \ / ___ . . .--. /
`. . \.-.--- `--' .'
`. `-' . .'
`. o / | O . .'
`-. / | o .-'
`-. . . .-'
`----. . .----'
`--------------'
```
```
Select: Sky dome, Alt/az sky, Solar system, Earth, Moon, No trails
CET 20:33:26 8/01/2023
LST 12:01:09
.--------------.
.----' o . `----.
.-' . O . . `-.
.-' @@@@@@ . `-.
.'@ @@@@@@@@@@@ @@@@@@@@ . `.
.'@@ @@@@@@@@@@@@@@ @@@@@@@@@@ `.
.'@@@ o @@@@@@@@@@@@@@ @@@@@@@@@@ o `.
/@@@ @@@@@@@@@@@@@@ @ @@@@@@@@@@ @@ . \
/ @@@@@@@@@@@ . @@ @@@@@@@@@@@@ @@ \
/@ o . @@@@@@ o @ @@@@@@@@@@@@@@ o @@@@ \
/@@@ . @@@@@@@@@@@@@@@ @@@@@ \
/@@@@@ @ . @@@@@@@@@@@@@@ @@@ \
|@@@@@ o `.-./ . @@@@@@@@@@@@ @@@ . |
/ @@@@@ __`-' o @@ . @@@@@@ \
|@ @@@@ . @ ` @ @@ . @@@@@@ | First Quarter +
| @@ @ o @@@ o @@@@@@. | 6 20:25:13
| @ @@@@@ @@@ | Full Moon -
| . . @ @ @ o @@@@@ . . | 0 0:00:00
\ @ .-. . @@@ . . /
| @ @ @ @ `-' . /
\ . @ @ . o /
\ o @@@@ . . /
\ @@@ @@@@@@ . o /
\ @@@@@ @@\@@ / o . /
\ o @@@ \ \ / ___ . . .--. /
`. . \.-.--- `--' .'
`. `-' . .'
`. o / | O . .'
`-. / | o .-'
`-. . . .-'
`----. . .----'
`--------------'

```

My guess was: Some messup with daylight saving time being applied (to UTC dates) when it shouldn't (would explain the extra hour), plus some outdated ephemerides for the remaining 00:01:52. But when I researched further, things get confusing...

Current XEphem 4.1 has full moon occur on 2023-08-01T18:33:44Z. Different sources give the times as 18:31Z or 18:33Z, depending on the website one checks.

### NASA JPL Horizons

NASA JPL Horizons with geocentric, airless gives the greatest illumination around 1841Z, which lasts for 3 minutes at the given precision. That may explain why most sources disagree about 3 minutes.

```
*******************************************************************************
Ephemeris / PORT_LOGIN Tue Aug 8 14:22:20 2023 Pasadena, USA / Horizons
*******************************************************************************
Target body name: Moon (301) {source: DE441}
Center body name: Earth (399) {source: DE441}
Center-site name: GEOCENTRIC
*******************************************************************************
Start time : A.D. 2023-Aug-01 18:30:00.0000 UT
Stop time : A.D. 2023-Aug-01 19:00:00.0000 UT
Step-size : 1 minutes
*******************************************************************************
Target pole/equ : MOON_ME {East-longitude positive}
Target radii : 1737.4, 1737.4, 1737.4 km {Equator_a, b, pole_c}
Center geodetic : 0.0, 0.0, -6378.137 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 0.0, 0.0, 0.0 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : ITRF93 {East-longitude positive}
Center radii : 6378.137, 6378.137, 6356.752 km {Equator_a, b, pole_c}
Target primary : Earth
Vis. interferer : MOON (R_eq= 1737.400) km {source: DE441}
Rel. light bend : Sun {source: DE441}
Rel. lght bnd GM: 1.3271E+11 km^3/s^2
Atmos refraction: NO (AIRLESS)
RA format : HMS
Time format : CAL
Calendar mode : Mixed Julian/Gregorian
EOP file : eop.230806.p231030
EOP coverage : DATA-BASED 1962-JAN-20 TO 2023-AUG-06. PREDICTS-> 2023-OCT-29
Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO )
Table cut-offs 2: Solar elongation ( 0.0,180.0=NO ),Local Hour Angle( 0.0=NO )
Table cut-offs 3: RA/DEC angular rate ( 0.0=NO )
******************************************************************************************************************
Date__(UT)__HR:MN phi PAB-LON PAB-LAT Illu% Def_illu ang-sep/v SN.ang SN.dist TDB-UT
******************************************************************************************************************
$$SOE
2023-Aug-01 18:30 4.9116 308.9234 -2.4651 99.81640 3.6807 0.0/* 164.36 85.82 69.183292
2023-Aug-01 18:31 4.9114 308.9291 -2.4650 99.81641 3.6803 0.0/* 164.24 85.82 69.183292
2023-Aug-01 18:32 4.9112 308.9347 -2.4649 99.81643 3.6801 0.0/* 164.13 85.81 69.183292
2023-Aug-01 18:33 4.9111 308.9403 -2.4648 99.81644 3.6798 0.0/* 164.01 85.81 69.183292
2023-Aug-01 18:34 4.9109 308.9460 -2.4647 99.81645 3.6796 0.0/* 163.89 85.81 69.183292
2023-Aug-01 18:35 4.9108 308.9516 -2.4646 99.81646 3.6794 0.0/* 163.77 85.81 69.183292
2023-Aug-01 18:36 4.9107 308.9573 -2.4645 99.81647 3.6793 0.0/* 163.65 85.80 69.183292
2023-Aug-01 18:37 4.9106 308.9629 -2.4644 99.81647 3.6791 0.0/* 163.53 85.80 69.183292
2023-Aug-01 18:38 4.9105 308.9686 -2.4644 99.81648 3.6790 0.0/* 163.41 85.80 69.183292
2023-Aug-01 18:39 4.9105 308.9742 -2.4643 99.81648 3.6790 0.0/* 163.29 85.80 69.183292

2023-Aug-01 18:40 4.9104 308.9799 -2.4642 99.81649 3.6789 0.0/* 163.17 85.80 69.183292
2023-Aug-01 18:41 4.9104 308.9855 -2.4641 99.81649 3.6789 0.0/* 163.05 85.80 69.183292
2023-Aug-01 18:42 4.9104 308.9912 -2.4640 99.81649 3.6790 0.0/* 162.93 85.80 69.183292

2023-Aug-01 18:43 4.9105 308.9968 -2.4639 99.81648 3.6790 0.0/* 162.81 85.80 69.183292
2023-Aug-01 18:44 4.9105 309.0024 -2.4638 99.81648 3.6791 0.0/* 162.69 85.80 69.183292
2023-Aug-01 18:45 4.9106 309.0081 -2.4637 99.81647 3.6792 0.0/* 162.57 85.80 69.183292
2023-Aug-01 18:46 4.9107 309.0137 -2.4637 99.81647 3.6793 0.0/* 162.45 85.81 69.183292
2023-Aug-01 18:47 4.9108 309.0194 -2.4636 99.81646 3.6795 0.0/* 162.33 85.81 69.183292
2023-Aug-01 18:48 4.9109 309.0250 -2.4635 99.81645 3.6797 0.0/* 162.21 85.81 69.183292
2023-Aug-01 18:49 4.9111 309.0307 -2.4634 99.81644 3.6800 0.0/* 162.10 85.81 69.183292
2023-Aug-01 18:50 4.9112 309.0363 -2.4633 99.81643 3.6802 0.0/* 161.98 85.82 69.183292
2023-Aug-01 18:51 4.9114 309.0420 -2.4632 99.81641 3.6805 0.0/* 161.86 85.82 69.183292
2023-Aug-01 18:52 4.9116 309.0476 -2.4631 99.81640 3.6808 0.0/* 161.74 85.82 69.183292
2023-Aug-01 18:53 4.9119 309.0533 -2.4630 99.81638 3.6812 0.0/* 161.62 85.83 69.183292
2023-Aug-01 18:54 4.9121 309.0589 -2.4629 99.81636 3.6816 0.0/* 161.50 85.83 69.183292
2023-Aug-01 18:55 4.9124 309.0646 -2.4629 99.81634 3.6820 0.0/* 161.38 85.84 69.183292
2023-Aug-01 18:56 4.9127 309.0702 -2.4628 99.81632 3.6824 0.0/* 161.26 85.84 69.183292
2023-Aug-01 18:57 4.9130 309.0758 -2.4627 99.81630 3.6829 0.0/* 161.14 85.85 69.183292
2023-Aug-01 18:58 4.9133 309.0815 -2.4626 99.81627 3.6834 0.0/* 161.02 85.85 69.183291
2023-Aug-01 18:59 4.9137 309.0871 -2.4625 99.81624 3.6839 0.0/* 160.90 85.86 69.183291
2023-Aug-01 19:00 4.9140 309.0928 -2.4624 99.81622 3.6845 0.0/* 160.78 85.87 69.183291
$$EOE
******************************************************************************************************************
```
Hmm, today I learned that there is no single answer to when a full moon occurs, evidently, so maybe the only fix you could reasonably make is about the DST being applied incorrectly.

Cheers!