The mythological association between Venus and the sun has an astronomical foundation.
Aveni suggests that it reflects Venus' "unique visual relationship to the sun".
Kukulkan was a post-Classical deity, perhaps introduced to the Maya by the Toltecs, who were influential at Chichen Itza and other centres in the northern Yucatan. Kukulkan is illustrated in the Venus pages of the Dresden Codex, which was compiled in the post-Classical period, probably after 1200 AD.
These divisions in the synodic period are almost certainly intended to mark the four principal apparitions of Venus - visibility as morning star, invisibility at superior conjunction, visibility as evening star, and invisibility at inferior conjunction.
Venus' period of visibility as morning star begins with its heliacal rise--- the date on which it rises with the sun.
Although the earliest representation of the Tlaloc warrior costume in the Mayan area (memorializing the conquest of Uaxactun by Tikal on 18.104.22.168.12 11, 16 January 378 AD) has has no astronomical significance, most inscriptions illustrating the Tlaloc costume do.
The astonishing murals at Bonampak illustrate a victory on 22.214.171.124.15 (16 August 792 AD), within a day or two of the heliacal rise of Venus.
When it rises at sunset once again, it is lost behind the earth's shadow at inferior conjunction before re-appearing again as morning star.
Above the red numbers (separated from them by a block of text) are black numbers that record a running total from page 46 to page 50.
The timing of wars to coincide with the rise of Venus was adopted in the Maya area in the Classical period, and is associated with "Tlaloc war cult", which seems to have originated at Teotihaucan in Central Mexico.
Tlaloc is the Aztec name of the central Mexican rain god, who, like his Maya counterpart Chac, has Venus associations.
Cosmical rise, when Venus rises at sunset in the west, is associated with evening and death.