Archaeoastronomy and Cultural Astronomy - the Astronomy of Skyscapes
Arising and Laying Hidden Stars: their celestial dynamics and role in Neolithic Iberian Cosmology
Fabio Silva
Institut Català de Palaeocologia Humana i Evolución Social (IPHES)
Based on their nightly dynamics throughout the year, there are four distinct stellar phase-types: the circumpolar stars, the curtailed passage (CP) stars, the Arising and Laying Hidden stars (ALH), and the invisible stars (eg. Brady 2015). This paper will focus on the ALH-type stars, whose dynamics are the most recognizable. ALH-type stars go through a period where they rise and set during the daytime and, therefore, remain absent from the night-sky. Many cultures, both historical and traditional (eg Hugh-Jones 2015), recognized this period portraying it (eg. the Roman ‘dog days’ corresponding to Sirius’ period of invisibility), lent meaning to this period, and weight to the stars’ first appearance, at dawn, just before sunrise – what is known as the heliacal rising.

This paper will describe the dynamics of this stellar phase-type and discuss a few well-known historical and ethnographic examples of societies that recognized, lent meaning to, and used ALH-stars for cultural purposes. It will then detail current work done among the western Iberian passage graves from the Middle Neolithic period (4,300 to 3,700 BCE) whose entrances aligned to bright stars of the (modern) constellations of Taurus and Orion. These essentially pastoral communities used the dynamics of these stars to mark their seasonal activities, including the transhumant motion between high pastures in the summer and lower valleys in the winter (eg Silva 2015).
16:30 - 18:00
EX - C3 (150)