Editing Astronomy (section)

==The Sun and Moon==
[[File:House Tarth.svg|right|thumb|350px|The [[sigil]] of [[House Tarth]] depicts the [[sun]] and [[moon]].]]
In the known world, a year is the length of a solar cycle, how long it takes the earth to make one complete revolution around the [[sun]].{{Ref|SSM|2997}}{{Ref|SSM|1034}} The world is also orbited by a [[moon]], in a similar fashion to Earth's, which revolves around the world twelve times a year.{{Ref|SSM|2997}} As on Earth, a year is measured by determining the position of the sun, moon, and stars.{{Ref|SSM|1034}}

The known world experiences extremely long [[seasons]] of varying length, usually lasting at least a couple of years each. It is known that the [[Measurement|daytime period]] is correlated with the seasons. Towards the end of [[Summer (season)|summer]], the days start to grow shorter,{{Ref|AGOT|21}} a trend which continues through [[autumn]].{{Ref|AFFC|20}}{{Ref|ADWD|21}} The end of a season is determined by the [[Conclave]] of the [[Citadel]], who base their conclusion on the measurements and reports of maesters all over the [[Seven Kingdoms]].{{Ref|ACOK|0}}

In his ''[[The Measure of the Days]]'', Maester [[Nicol]] argues, based upon his studies on the movement of stars, that the seasons possibly were once of a regular length, determined by the way in which the globe faces the sun. According to Maester [[Yandel]], however, although the notion appears to be true, Nicol has not been able to find any evidence that regular seasons were once the case, beyond the most ancient of tales.{{Ref|TWOIAF|Ancient History: The Long Night}}

The [[Qartheen]] believe that there were once two moons in the sky. This second moon supposedly came too close to the sun and cracked like an egg hatching, releasing a million [[dragon]]s.{{Ref|AGOT|23}}{{Ref|TWOIAF|Ancient History: The Rise of Valyria}} The [[Dothraki]] believe that the moon is a goddess, wife to the sun.{{Ref|AGOT|23}} A Dothraki husband may refer to his wife as "moon of my life", to which she responds, calling him "my sun-and-stars".{{Ref|AGOT|46}}

In the faith of [[R'hllor]], the Lord of Light, the [[red priest]]s and other followers pray before a nightfire, thanking R'hllor for ending the day, while beseeching him to bring the dawn and banish the darkness.{{Ref|ASOS|63}} The nightfires are lit at sunset.{{Ref|ASOS|63}}{{Ref|AGOT|3}} Fires are also lit each morning at first light, where the red priests welcome the sun.{{Ref|AFFC|0}} Other red priests might attend to their fires during the entire night.{{Ref|ADWD|33}} A common phrase in this faith is "the night is dark and full of terrors".{{Ref|ACOK|0}}{{Ref|AFFC|0}} A typical prayer includes the sequence,
{{lyrics|
Yours is the sun that warms our days, yours the stars that guard us in the dark of night.
:(Lord of Light, defend us. The night is dark and full of terrors. Lord of Light, protect us.) 
R'hllor who gave us breath, we thank you. R'hllor who gave us day, we thank you. 
:(We thank you for the sun that warms us. We thank you for the stars that watch us. 
:We thank you for our hearths and for our torches, that keep the savage dark at bay.){{Ref|ASOS|63}}<ref group="N">The sentences in parentheses are responses from worshippers present at the nightfire.</ref>}}