Xamidimura — さそりの二重星

Xamidimura, Mu1 Scorpii, is a B-type giant of spectral class B1.5 IV about 490 light-years away — a massive, hot, young star in the dense stellar associations of Scorpius-Centaurus. It pairs with Pipirima (Mu2 Sco) to form a naked-eye double. Xamidimura itself is an eclipsing binary, shedding 0.3 magnitudes over a 1.4-day period as a companion B-star transits across its disk. Total combined mass for Xamidimura's binary pair is about 16 solar masses.

Xamidimura and Pipirima form a bright naked-eye pair south of the main Scorpius outline, about 0.3 degrees apart. The two blue-white stars together make a conspicuous double visible even from moderately light-polluted skies. Xamidimura is slightly the brighter of the two. Best observed in the southern hemisphere May through September; challenging from high northern latitudes.

The name Xamidimura comes from the Khoekhoe language of southern Africa, meaning "the eyes of the lion" — paired with Pipirima's Tupi origin, the two stars bear rare non-Eurasian IAU-recognized names. The IAU adopted both names in 2017, in a deliberate effort to include indigenous astronomical traditions in the official nomenclature.