Astronomy Picture of the Day . Orion over El Castillo . ... Astronomia UNAM ), P. S nchez and R. Nafate ( INAH ) Explanation: Welcome to the December solstice , a day the world does not end ... even according to the Mayan Calendar. To celebrate, consider this dramatic picture of Orion rising over El Castillo , the central pyramid at Chich n Itz , one of the great Mayan centers on the Yucat n peninsula. ... Publications with keywords: solstice . ... Equinox: The Sun from Solstice to Solstice . ...