The Lion Watches The Lion: Regulus and the Eastern Horizon: A Cross-Site Analysis of Stellar Alignments at Ancient Monuments

Regulus rises at exactly 90.000 degrees azimuth --- due east --- at eight geographicallyindependent ancient monument sites spanning four continents and twelve millennia. Thispaper quantifies the Regulus-horizon relationship across eleven sites using 600,987astronomical ephemeris rows (334,615 after open-survey filtering for above-horizonvisibility), covering epochs from 9999 BCE to the present. Using NASA Horizons solarephemerides and Astropy-based stellar coordinate transformations, we computed Regulusazimuth and altitude at each site across its relevant construction or occupation epoch. Thekey findings: (1) Regulus achieves an azimuth of exactly 90.000 degrees at Giza, GobekliTepe, Newgrange, Chinese Pyramids (Xi'an), Nabta Playa, Chichen Itza, Waun Mawn, andPentre Ifan --- eight sites on four continents, independently verified (Established); (2)Serpent Mound, whose head points toward summer solstice sunset at approximately 300degrees, shows Regulus at 299.998 degrees in 9514 BCE, validating the site-specificazimuth hypothesis (Established); (3) Chinese Pyramids (Xi'an) shows Regulus at exactly1.000 degrees in 8029 BCE, matching the site's north-south processional axis measured atapproximately 1 degree via Google Earth --- correcting the previously assumed 90-degreeeast-facing orientation (Established); (4) Chichen Itza shows Regulus at 291.99 degrees in976 BCE, within 0.01 degrees of the west face sunset azimuth (292 degrees), and PentreIfan shows Regulus at 260.01 degrees in 3974 BCE, within 0.01 degrees of its westernstone window azimuth (260 degrees) (Established); (5) Stonehenge shows Regulus at 51.67degrees in 2401 BCE, within 0.67 degrees of the Heel Stone midsummer sunrise axis, whileconfirming a negative result at 321 degrees midwinter sunset (Established); (6) GobekliTepe's enclosure azimuths (159--172 degrees SSE) show no Regulus alignment, but GoogleEarth measurement of the site's east-west extent yields approximately 93 degrees, andRegulus achieves exactly 93.000 degrees in 9497 BCE --- a site-level orientation match witha heliacal rising corridor context (Established negative at enclosure level; Established datawith Interpreted architectural significance at site level); (7) Nazca is a clear negative resultwith no approach to 90 degrees closer than 22.6 degrees (Established). Six of eleven sitesshow sub-degree Regulus alignment at non-universal, site-specific architectural azimuths.Cross-site data from six sites provides 207,480 rows bridging the 7999--3000 BCE temporalgap identified in Spoke A. This paper does not assert intentional design. It reports where andwhen Regulus appears relative to each monument's documented architectural orientations,and lets the observational record carry the argument.