Orion's Belt

This article is about the group of stars within the constellation Orion. For other uses, see Orion's Belt (disambiguation).

Astrophotograph of Orion's Belt.

Orion's Belt or The Belt of Orion is an asterism in the constellation Orion. It consists of the three bright stars: ζ Ori (Alnitak), ε Ori (Alnilam), and δ Ori (Mintaka). Alnitak is approximately 800 light years away from Earth and, taking into consideration ultraviolet radiation, which the human eye cannot see, Alnitak is 100,000 times more luminous than the Sun.^[1] Alnilam is approximately 1340 light years away from earth and shines with magnitude 1.70. Considering ultraviolet light Alnilam is 375,000 times more luminous than the Sun.^[2] Mintaka is 915 light years away and shines with magnitude 2.21. Mintaka is 90,000 times more luminous than the Sun. Mintaka is a double star. Both stars orbit around each other every 5.73 days.^[3] Looking for Orion's Belt in the night sky is the easiest way to locate the constellation Orion in the sky. In the Northern hemisphere, Orion's Belt is best visible in the night sky during the month of January at around 9.00 pm.^[4]

The same three stars are known in Latin America as "The Three Marys".^[5] They also mark the northern night sky when the sun is at its lowest point, and were a clear marker for ancient timekeeping. In Puerto Rico they are called the Three Kings.^[6] The stars start appearing around the holiday of Epiphany, when the Biblical Magi visited the baby Jesus, which falls on January 6.

Richard Hinckley Allen lists many folk names for the Belt of Orion. The English ones include: Jacob's Rod or Staff; Peter's Staff; the Golden Yard-arm; the L, or Ell; the Ell and Yard; the Yard-stick, and the Yard-wand; the Ellwand; Our Lady's Wand; the Magi; the Three Kings; the Three Marys; or simply the Three Stars.

The passage "Canst thou bind the sweet influences of Pleiades, or loose the bands of Orion?" is found in the Bible's Book of Job.

In the Star Trek episode The City on the Edge of Forever, Captain Kirk tells Edith Keeler that a famous poet from "a planet circling the far left star in Orion's Belt" will compose a poem based on the three words "Let Me Help."

Gallery

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  Map of Orion.

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  Amateur astrophotograph of Orion's Belt.

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  Astrophotograph of the region of Orion’s Belt and the Flame Nebula.

See also

• Orion (constellation)
• Orion's Sword
• Thornborough Henges
• Orion Correlation Theory

References

1. ^ http://stars.astro.illinois.edu/sow/alnitak.html
2. ^ http://stars.astro.illinois.edu/sow/alnilam.html
3. ^ http://stars.astro.illinois.edu/sow/mintaka.html
4. ^ http://www.astro.wisc.edu/~dolan/constellations/constellations/Orion.html
5. ^ Lenda de Órion e as Três Marias
6. ^ http://sepiensa.org.mx/contenidos/s_reyes/reyes.htm

• Richard Hinckley Allen: Star Names — Their Lore and Meaning