Galhafan year

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The Galhafan sidereal year is 259 days, 15 hours, 43 minutes, 18 seconds in Earth time, and in Galhafan time, 240 days, 21 hours, 34 minutes, 31 seconds.

The mean tropical year is 259 d, 15 h, 28 m, 59 s Earth time, 240 d, 21 h, 21 m, 14 s Galhafan time.

Vernal Equinox Year	259 d, 15 h, 29 m, 32 s	240 d, 21 h, 21 m, 45 s	240.8901001 d
Summer Solstice Year	259 d, 15 h, 31 m, 6 s	240 d, 21 h, 23 m, 12 s	240.8911057 d
Autumn Equinox Year	259 d, 15 h, 28 m, 44 s	240 d, 21 h, 21 m, 0 s	240.8895845 d
Winter Solstice Year	259 d, 15 h, 26 m, 35 s	240 d, 21 h, 19 m, 0 s	240.8881990 d

Third-Seasons

The Kasshi traditionally divided the solar year into 12 "third-seasons". The 2nd, 5th, 8th, and 11th half-seasons have the spring equinox, summer solstice, autumnal equinox, and winter solstice at their midpoint, the 1st, 4th, 7th, and 10th half-seasons start with the seasonal midpoints. The Kasshi considered the solstices and equinoxes to be the mid-points of the seasons, and thus, they counted the 1st, 2nd, and 3rd third-seasons as spring, the 4th-6th as summer, and so on.

Because Galhaf's orbit is moderately eccentric, the half-seasons vary in length by several days. The northern hemisphere's summer solstice occurred about 10º after perhelion in classical times.

I	20 d, 23 h, 52 m, 25 s	20.99473 d
II	19 d, 8 h, 17 m, 0 s	19.34514 d
III	18 d, 0 h, 35 m, 38 s	18.02475 d
IV	17 d, 6 h, 19 m, 23 s	17.26346 d
V	17 d, 3 h, 33 m, 12 s	17.14806 d
VI	17 d, 16 h, 31 m, 24 s	17.68847 d
VII	18 d, 19 h, 55 m, 19 s	18.83008 d
VIII	20 d, 9 h, 39 m, 40 s	20.40255 d
IX	22 d, 1 h, 2 m, 57 s	22.04372 d
X	23 d, 5 h, 0 m, 46 s	23.20887 d
XI	23 d, 9 h, 41 m, 19 s	23.40370 d
XII	22 d, 12 h, 52 m, 27 s	22.53643 d

Lunar Months

Galhaf's two moons co-orbit the planet, on average, once every 17 d, 1 h, 35 m, 44 s Galhafan time. The mean synodic month comes out to 18 d, 8 h, 49 m, 33 s, about 13.12 per year.