The Two Sky-Raisers (as-simakan)
In ancient Arabic, the term simak indicated something that was used to raise something else high up. When the Two Sky-Raisers reached the midpoint of their travels across the night sky, the uppermost one was almost at the zenith, right over your head, and the lower Sky-Raiser was almost directly below it, about halfway up the sky. The Two Sky-Raisers were the pillars that held up the canopy of the heavens.
A pair of very bright stars that are spaced widely apart.
α VIR (Spica), blue-white star, magnitude 1.0
α BOO (Arcturus), red giant star, magnitude 0.0
The Two Sky-Raisers set about 40 days apart but rise within a week of each other. Ibn Qutayba (d. 879 CE) reported that the Unarmed Sky-Raiser (the first of the pair to set and the second to rise) was said to rise on the morning of October 6 and set on the morning of April 5. On account of the precession of the equinoxes, today we can expect to observe the Two Sky-Raisers setting in late April and early June, and rising in late October, as seen from the latitude of Tucson. (See How to Observe on the About page for more on this topic.)
In the calendars of Qushayr and Qays, the morning settings of the Two Sky-Raisers defined the start and end of the short rainy season of summer (as-sayf).
Because the ecliptic (the path of the Moon against the stellar background) passes through the Unarmed Sky-Raiser, within the context of the lunar stations only it, and not the Spear-Bearing Sky-Raiser, had the honor of being a lunar station. In early listings of the lunar stations, the Unarmed Sky-Raiser is the 16th station of the year. This was later changed to the 14th lunar station after the stations were adjusted to begin with the vernal equinox.
Related Stars and Celestial Complexes
The Two Sky-Raisers are the primary stars of the Sky-Raisers (as-simakan, السماكان) folkloric celestial complex.
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