structural:summarization
Nomenclature

In 2016, the International Astronomical Union (IAU) included the name "Rigel" in the IAU Catalog of Star Names. According to the IAU, this proper name applies only to the primary component A of the Rigel system. The system is listed variously in historical astronomical catalogs as H II 33, Σ 668, β 555, or ADS 3823. For simplicity, Rigel's companions are referred to as Rigel B, C, and D; the IAU describes such names as "useful nicknames" that are "unofficial". In modern comprehensive catalogs, the whole multiple star system is known as WDS 05145-0812 or CCDM 05145–0812.

The designation of Rigel as β Orionis (Latinized to Beta Orionis) was made by Johann Bayer in 1603. The "beta" designation is commonly given to the second-brightest star in each constellation, but Rigel is almost always brighter than α Orionis (Betelgeuse). Astronomer James B. Kaler has speculated that Rigel was designated by Bayer during a rare period when it was outshone by the variable star Betelgeuse, resulting in the latter star being designated "alpha" and Rigel designated "beta". Bayer did not strictly order the stars by brightness, instead grouping them by magnitude. Rigel and Betelgeuse were both considered to be of the first magnitude class, and in Orion the stars of each class are thought to have been ordered north to south. Rigel is included in the General Catalogue of Variable Stars, but since it already has a Bayer designation it has no separate variable star designation.

Rigel has many other stellar designations taken from various catalogs, including the Flamsteed designation 19 Orionis (19 Ori), the Bright Star Catalogue entry HR 1713, and the Henry Draper Catalogue number HD 34085. These designations frequently appear in the scientific literature, but rarely in popular writing.