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Key Facts & Information
- Bellatrix is considered as the third-brightest star in the constellation of Orion. It is a slightly variable star between the first and second magnitude.
- In the night sky, it varies as the 25th and 27th brightest star.
- Bellatrix can be seen by the naked eye and was known to humanity throughout the ages.
- One of the first accounts that mentioned Bellatrix was in the works of Persian astronomer, Abu Ma’shar, in the 9th century. He used the name Bellatrix for the star Capella, but it was switched to Gamma Orionis by the Vienna school of astronomers in the 15th century.
- The works of Abu Ma’shar were later on translated from Arabic into Castilian by John Seville in the 12th century.
- Bellatrix is Latin for “female warrior”. It was also called Amazon Star, which comes from the Arabic name, Al Najid. This means “The Conqueror”. An even older Arabic name was used, which was “The Lion”.
- It has an estimated age of around 25 million years old.
- Bellatrix formed from a nebula of gas and dust around 25 million years ago. The swirling gas and dust were pulled together by gravity into becoming Bellatrix.
- It is enveloped in a growing outer shell of gaseous matter and it has started to evolve off the main-sequence star, and is on its way to becoming a true giant.
Distance, Size & Mass
- Bellatrix is the closest star to us compared to the other stars in the constellation. It is 250 light-years / 77 parsecs away from the Sun.
- It has 5.75 solar radii, which is 6 times that of the Sun’s radius and almost 12 times its diameter. It has 8.6 times more mass than our Sun.
- The star has a blue-white hue that typically occurs with B-type stars because of its high temperature, which is 4 times as hot as the Sun, or 22,000 K.
- It also emits light at a whopping 9.211 times the light of our Sun. It has a virtual magnitude between 1.59 and 1.64, and an absolute magnitude of -2.78.
- It could dominate the night sky if it was closer to us. Studies suggest that it is a binary star system with similar properties, but less luminous than a B2-type giant would be.
- It is a little fainter than Shaula in the Scorpius Constellation and Gacrux in Crux. It outshines Elnath in the Taurus Constellation, the same as Miaplacidus of Carina, and Alnilam.
- Bellatrix is located in the Orion Constellation, the celestial hunter. It is the third-brightest star next to Rigel and Betelgeuse.
- It marks the left shoulder of Orion, while Betelgeuse marks the right shoulder. It is one of the seven brightest stars that outline the hourglass figure.
- Since Bellatrix has started its transition into a true giant, it is expected to become an orange giant within a few million years. Since it has more than 8 times the Sun’s mass, it is also close to being considered a supernova candidate.
Did You Know?
- Bellatrix, Betelgeuse, and Meissa mark the head of Orion. They are considered as the Euphratean Constellation of the King, Kabbab Sar, and were believed to bring good fortune, wealth, and military honors.
- The Iniut knew Bellatrix and Betelgeuse as Akuttujuuk, which translates to “those two placed far apart”.
- In the Northern Territory of Australia, the Wardaman people called the star Banjan.
- To the Chinese, Bellatrix was the Fifth Star of the Three Stars asterism which originally included Orion’s Belt stars, Alnilam, Alnitak and Mintaka.
- Bellatrix and the other stars of Orion can be best seen when the constellation dominates the evening sky in January.