Three sisters in the sky – the truth and the myth

If you look up at the night sky, especially between November to February, there are three stars that catches the eye of anyone – you don’t need to be a star gazer to notice this. Orion’s Belt or the Belt of Orion, also known as the Three Kings or Three Sisters. Alnitak, Alnilam and Mintaka – the bright stars located in the Orion Constellation is an asterism. Although these three stars look in line, they are actually millions miles apart.

According to an astronomer with the National Radio Astronomy Observatory, Ronald Maddlaena, these are the meanings of the three stars: Mintaka (on the west) means “belt”, Alnilam (in center) means “belt of pearls” or “string of pearls”and Altnitak (right) means “girdle.”

Few deets about the stars:

• Alnitak(Zeta Orionis): A triple star system, which means three other stars orbit around each other. It’s a blue supergiant that is located 1,260 light years from the Earth. It is 28 times as massive as our own Sun.
  • Constellation: Orion
  • Coordinates: RA 05h 40m 45.52666s |Dec. -01° 56′ 34.2649″
  • Distance: 1,260 light years
  • Star Type: O9.5Iab
  • Mass: 33 sol
  • Radius: 20 sol
  • Apparent Magnitude: +2.08
  • Luminosity: 250,000 sol
  • Surface Temperature: 29,500K
  • Rotational Velocity: 110 km/sec
  • Age: ± 6.4 million years
  • Other Designations: Zeta Orionis, 50 Orionis, 126 G. Orionis, BD-02°1338, SAO 132444, HIP 26727, TD1 5127, WDS J05407-0157

• Alnilam(Epsilon Orionis): This one is also a blue supergiant, approximately 2,000 light years away from Earth. Known 29th brightest star in the night sky and is 375,000 times more luminous than the Sun.
  • Constellation: Orion
  • Coordinates: RA 05h 36m 12.8s |Dec. -01° 12′ 06.9″
  • Distance: 2,000 light years
  • Star Type: B0 Ia
  • Mass: 30-64.5 sol
  • Radius: 42 sol
  • Apparent Magnitude: Variable between +1.64 and +1.74
  • Luminosity: 275,000 – 832,000 sol
  • Surface Temperature: 27,000K
  • Rotational Velocity: 40-70 km/sec
  • Age: 5.7 million years
  • Other Designations: e Ori, 46 Orionis, 112 G Orionis, HR 1903, BD -01°969, HD 37128, SAO 132346, FK5 210, HIP 26311, TD1 4963

• Mintaka(Delta Orionis): The west most end of the Orion’s belt, its about 1,200 light years away from Earth. It is 90,000 times more luminous than the Sun. It is a double (binary) star system, the two stars orbit around each other every 5.73 days.
  • Constellation: Orion
  • Coordinates d Ori A (Aa1 + Aa2 + Ab)): RA 05h 32m 00.40009s|Dec. -00° 17′ 56.7424″
  • Distance: ± 1,200 light years
  • Apparent Magnitude (d Ori A (Aa1 + Aa2 + Ab)): 2.23 (2.50 + 3.90)
  • Luminosity (d Ori A (Aa1 + Aa2 + Ab)): 190,000 sol

Fun facts and beliefs:

• Constellations and asterisms change over time as a result of stars moving throughout space (rotation & revolution). However, these three stars in the Orion’s belt share the same origin and have been in the same motion over centuries. This means, this is how they looked during ancient times as it does now.
• The famous three Egyptians pyramids perfectly align with the Orion’s belt and the air shafts inside the pyramid point directly towards the Orion’s constellation. They believed that it is set that way to project Pharaoh’s soul towards Orion. Theory or not, but the alignment between the stars and the pyramids are quite exceptional. Orion’s orientation to the Milky Way matches the pyramids’ orientation to the river Nile.

• The pyramid of the Moon and the Sun located in the city of Teotihuacán, Mexico is said to have built and point directly to Orion’s belt.

If you want to study the night sky, personally I would recommend to identify these three in the night sky. The space where they are located is the Orion’s constellation (the Hunter) with other stars such as Betelgeuse, Bellatrix, Saiph, Rigel . More on that later.