Re: Equinox – lygiadienis

On Sep 21, 11:16 pm, tadas.bli...@xxxxxxxx wrote:
On 22 Rugs, 09:03, Pēteris Cedriņš (Peteris Cedrins)





<cedr...@xxxxxxxxx> wrote:
tadas.bli...@xxxxxxxx rakstīja:

There is either an equinox (autumn and spring) or a solstice (summer
and winter) on approximately the 21st day of the last month of every
quarter of the calendar year. On a day which has an equinox, the
centre of the Sun will spend a nearly equal amount of time above and
below the horizon at every location on Earth and night and day will be
of nearly the same length. The word equinox derives from the Latin
words aequus (equal) and nox (night). In reality, the day is longer
than the night at an equinox. Commonly, the day is defined as the
period that sunlight reaches the ground in the absence of local
obstacles. From Earth, the Sun appears as a disc and not a single
point of light; so, when the centre of the Sun is below the horizon,
the upper edge is visible. Furthermore, the atmosphere refracts light;
so, even when the upper limb of the Sun is below the horizon, its rays
reach over the horizon to the ground. In sunrise/sunset tables, the
assumed semidiameter (apparent radius) of the sun is 16 minutes of arc
and the atmospheric refraction is assumed to be 34 minutes of arc.
Their combination means that when the upper limb of Sun is on the
visible horizon its centre is 50 minutes of arc below the geometric
horizon, which is the intersection with the celestial sphere of a
horizontal plane through the eye of the observer. These effects
together make the day about 14 minutes longer than the night at the
equator, and longer still at sites toward the poles. The real equality
of day and night only happens at places far enough from the equator to
have at least a seasonal difference in daylength of 7 minutes, and
occurs a few days towards the winter side of each equinox.

~~~~~~~~~~~~~~~~~~

Lygiadienis (ankstesn je literat roje galima rasti pavadinim
ekvinokcija) tai momentas ruden ir pavasar kai Saul , slinkdama
ekliptika, atsiduria dangaus pusiaujo ir ekliptikos susikirtimo
ta kuose. Tuo metu diena ir naktis susilygina visose em s platumose.

Tai atsitinka tada, kai emei skriejant aplink Saul , steb tojui Saul
atsiduria dangaus pusiaujyje.

Lygiadieni ta kai ymimi tais pat enklais, kuriuose jie buvo prie
2000 met . Dabar pavasario lygiadienio ta kas yra uv vaig dyne, o
rudens lygiadienio ta kas - Mergel s vaig dyne.

iaurinio pusrutulio gyventojams pavasario lygiadienis (kovo 20) yra
astronominio pavasario prad ia, o rudens lygiadienis (rugs jo 22) -
astronominio rudens prad ia. Piet pusrutulio gyventojams -
atvirk iai, kovo 20 yra j astronominio rudens prad ia.

Per 90 laipsni nuo lygiadienio ta k yra nutol saul gr os ta kai.
Pavasario lygiadienio ta ke ( ymimas Avino enklu) Saul pereina i
pietinio dangaus iaurin (dangaus pusiaujo at vilgiu), rudens
lygiadienio ta ke ( ymimas Svarstykli enklu) Saul pereina i
iaurinio dangaus pietin .

    * Pavasario lygiadienis b na kovo 20 arba kovo 21 dien (Balt
vent - Pavasario lyg ).
    * Rudens lygiadienis b na rugs jo 22 arba rugs jo 23 dien (Balt
vent - Dagos (arba Rudens lyg ).

Labas rytas,

What's the etymology of "lygiadienis"? In Latvian, the equinox is
saulstāvji -- ("stāvēt" -- to stand; "stāvs" -- your "stovus"). The
autumnal equinox is also Apjumības, the catching of Jumis, though this
shifts to Michaelmas --

http://en.wikipedia.org/wiki/Mikeli

http://www.liis.lv/folklora/gadsk/origin/mikeli.htm

Geriausio,
/P

http://lettonica.blogspot.com/

Labrît

Lygus = equal; diena...  it's staring you in the face.  :-)

Too bad about the diacritics.  

It might mean 'equal' in Lithuanian now.. and it might be a related
form of Latv. 'liidziigs (meaning 'similar'); but I believe I have
discovered the Latv. 'liiks'/'liigs' had a original meaning of
'turning' or 'bending'... ie.. when the earth 'turns' in its orbit.

The implication of arcane knowledge of orbital mechanics is possible.

The Latv. midsummer festival is called 'Ligo'.. and midsummer is not
associated with equal days and nights.






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