Lambda Orionis
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| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Orion |
| Right ascension | 05h35m08.28s |
| Declination | +09°56′02.96″ |
| Apparent magnitude (V) | 3.39 / 5.61 |
| Characteristics | |
| Spectral type | O8III / B0.5V |
| U−B color index | −1.03 / −0.77 |
| B−V color index | 0.18 / 0.04 |
| Variable type | none |
| Astrometry | |
| Radial velocity (Rv) | +33.5 km/s |
| Proper motion (μ) | RA: −2.1 mas/yr Dec.: −2.9 mas/yr |
| Parallax (π) | 3.09 ± 0.78 mas |
| Distance | approx. 1100 ly (approx. 320 pc) |
| Absolute magnitude (MV) | −4.25 / -1.94 |
| Details | |
| Mass | 16 / 4 M☉ |
| Luminosity | 63,000 / 7,500 L☉ |
| Temperature | ~33,000 / ~31,000 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
Lambda Orionis (λ Ori, λ Orionis) is a star in the constellation Orion. It has the traditional names Meissa or Heka. "Meissa" derives from the Arabic "Al-Maisan" which means "The Shining One". This term was used for Gamma Gemini (Alhena), but was somehow also mistakenly applied to λ Orionis and the name stuck. The original Arabic name for this star, "Al Hakah", the source for "Heka", refere to the Arabic lunar mansion include this star and the both of φ Ori (Al Haḳʽah, "a White Spot").[1]
In Chinese, 觜宿 (Zī Sù), meaning Turtle Beak (asterism), refers to an asterism consisting of λ Orionis and both of φ Ori[2] Consequently, λ Orionis itself is known as 觜宿一 (Zī Sù yī, English: the First Star of Turtle Beak.)[3]
Meissa is a blue spectral type O giant star and is part of the Collinder 69 star cluster. It has an apparent visible magnitude 3.39.
Meissa is actually a binary star system. The fainter star is of magnitude 6 and is 4.4 seconds of arc away from the brighter. It is a hot blue-white dwarf of spectral type B0.5 V.
[edit] References
- ^ Allen, R. H. (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York, NY: Dover Publications Inc. p. 318. ISBN 0486210790. http://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Orion*.html. Retrieved 2011-07-16.
- ^ (Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 9789867332257.
- ^ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 24 日
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