Betelgeuse is an immense red supergiant approximately 548 to 700 light-years from Earth. As the second brightest star in its constellation, Betelgeuse is easily discernible by its distinctive reddish-orange hue, which hints at its final stage of stellar life. The star is also known as Alpha Orionis, but its traditional name is frequently mispronounced and misspelled. This name masks a history rooted in an ancient linguistic error that traces back through centuries of astronomical observation and manuscript transcription.
The Star’s Location in Orion
Betelgeuse holds a prominent visual position within the constellation of Orion, the Hunter. Ancient observers identified the star as marking the eastern or right shoulder of the figure, a placement that helped define the constellation’s shape. This location contrasts sharply with the star’s neighbor, Rigel, which marks the Hunter’s foot or knee.
For early astronomers, the physical location of the star relative to the celestial figure was the most logical way to identify it. They looked to the body of the celestial giant, al-Jawzā’, to anchor their naming convention. The star’s visual role as a shoulder or armpit was the direct inspiration for the original Arabic descriptive name.
Identifying the Original Arabic Phrase
The origin of the name Betelgeuse lies in the specific phrases used by classical Arabic astronomers during the Middle Ages. The most widely accepted original term is Yad al-Jawzā’, which literally translates to “the Hand of al-Jawzā’.” The term al-Jawzā’ refers to the central figure, the giant hunter Orion.
Some sources suggest the original term may have been Ibt al-Jawzā’, meaning “the Armpit of al-Jawzā’.” Both phrases describe the star’s upper placement relative to the torso of the celestial giant. These descriptive names accurately reflected the star’s perceived location before they were corrupted by transliteration.
The Linguistic Error That Created “Betelgeuse”
The modern name Betelgeuse is the result of an enduring scribal error that occurred during the translation of Arabic astronomical texts into Latin. This transcription process often took place in Spain during the medieval period, where Arabic manuscripts were diffused across Europe. The original Arabic word for “hand,” Yad (or Ibt for armpit), begins with the Arabic letter yā’, which is written with two dots beneath it.
The error occurred when the initial letter was misread as bā’, which looks nearly identical but has only a single dot beneath it. This tiny difference in the diacritical mark corrupted the word Yad or Ibt into Bait or Bat. This misreading changed the meaning from “Hand of Orion” to a nonsensical phrase like Bait al-Jawzā’.
This corrupted word, beginning with ‘B-t’, was then Latinized and transcribed into European languages, becoming Bedalgeuze or similar spellings. The final form “Betelgeuse” solidified in the 17th century, notably appearing in the star charts of the German astronomer Johann Bayer. Thus, the star’s current name is the result of a small transcription error made centuries ago.