Length of the Night
as an interval between the PM and AM moments
of Sun passing a given angular height (default -6°, for the ``civil night''):
The centre of Sun is at a place with coordinates [Lambda=16.6°, Phi=49.2°]
in an angular height of h =-6.0°
in the following morning and evening moments (given in UTC+ 2h):
year-month-day morning evening twilight decl. >mean night A-W
h:min / 1 min /1° /1min /1h /1°
2024- 4-26 Friday 5: 5 20:38 35.4 13.75 2.2 8.45 29.2
27 Saturda 5: 3 20:40 35.5 14.07 2.4 8.39 29.7
28 Sunday 5: 1 20:41 35.7 14.39 2.5 8.33 30.3
Average for 3 days
from 3 values is 5: 3 20:40 35.5 14.07 2.4 8.39 29.7
Meaning of remaining columns:
Twilight is an interval to/from h=-0.8°
Declination of Sun is given for the moment of local mean noon,
>Mean says how much is the Sun ahead of the mean time,
Night is the time the Sun travels below h,
A-W is departure of solar azimuth from the west when at h afternoon.
This is a result of the programme
nights (available as a part of a package
pas_jh.zip (1.2 MB) --
the needed Pascal units themselves are unzipped within
this directory, the whole tree of my programmes within
this directory)
with a command line:
nights d26.04.2024 t09:16 l16.6 f49.2 ut2 h-6 n2 i1