Beta Andromedae

This article is about the star. For the target drones, see Galileo Mirach 150 and Galileo Mirach 26.

β Andromedae

β Andromedae is left of center
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Andromeda
Right ascension	01h 09m 43.9236s[1]
Declination	+35° 37′ 14.008″[1]
Apparent magnitude (V)	2.01 to 2.10[2]
Characteristics
Spectral type	M0III[1]
U−B color index	+1.96[3]
B−V color index	+1.58[3]
V−R color index	0.9[1]
R−I color index	+1.00[3]
Variable type	Semiregular[2]
Astrometry
Radial velocity (Rv)	0.3 ± 0.9[1] km/s
Proper motion (μ)	RA: 175.59[1] mas/yr Dec.: −112.23[1] mas/yr
Parallax (π)	16.36 ± 0.76[1] mas
Distance	199 ± 9 ly (61 ± 3 pc)
Absolute magnitude (MV)	−1.9[4]
Details
Mass	3–4[5] M☉
Radius	90[5] R☉
Luminosity	1,900[5] L☉
Temperature	3,800[5] K
Other designations
Mirach, Merach, Mirac, Mizar, β And, Beta Andromedae, Beta And, 43 Andromedae, 43 And, BD+34°198, FK5 42, GJ 53.3, GJ 9044, HD 6860, HIP 5447, HR 337, LTT 10420, NLTT 3848, SAO 54471, WDS 01097+3537A.[1][6]
Database references
SIMBAD	data

Beta Andromedae (Beta And, β And, β Andromedae) is a red giant star in the constellation of Andromeda. It has the traditional name Mirach (also spelled Merach, Mirac, Mirak).^[6] It has spectral class M0, and is approximately 200 light years away.^[1] It is classified as a suspected semiregular variable star whose apparent visual magnitude varies from +2.01 to +2.10.^[2]

Observation

β Andromedae is located northeast of the Great Square of Pegasus and is theoretically visible to all observers north of 54° S. Its location in the sky is shown on the left. The galaxy NGC 404, also known as Mirach's Ghost, is visible seven arc-minutes away.^[7]

Naming and etymology

The name Mirach, and its variations, such as Mirac, Mirar, Mirath, Mirax, etc. (the name is spelled Merach in Burritt's The Geography of the Heavens)^[8] come from the star's description in the Alfonsine Tables of 1521 as super mizar.^[6] Here, mirat is a corruption of the Arabic ميزر mīzar "girdle", which appeared in a Latin translation of the Almagest.^[6] This word refers to Mirach's position at the left hip of the princess Andromeda.^[9]

Medieval astronomers writing in Arabic called β Andromedae Janb al-Musalsalah (English: The Side of the Chained (Lady)); it was part of the 26th manzil (Arabian lunar mansion) Batn al-Hũt, the Belly of the Fish, or Qalb al-Hũt, the Heart of the Fish.^[6][10] The star has also been called Cingulum and Ventrale.^[6]

This al-Hũt was an indigenous Arabic constellation, not the Western "Northern Fish" part of the constellation Pisces.^[10]

These names are not from the Arabic marãqq, loins, because it was never called al-Marãqq in Arabian astronomy.^[10]

Al Rishã', the Cord (of the well-bucket), on al-Sũfĩ's star map. It is origin of the proper name Alrescha for Alpha Piscium.^[6][11][12]

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism consisting of β Andromedae, η Andromedae, ζ Andromedae, ε Andromedae, δ Andromedae, π Andromedae, ν Andromedae, μ Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and Micronesia named this star as Kyyw "The Porpoise", and become once of Micronesian month name.^[15]

Mirach is listed in MUL.APIN as KA.MUSH.I.KU.E, meaning "the Deleter" (the alternative star is α Cas).^[16].

Notes and references

1. ^ ^{a b c d e f g h i j} NAME MIRACH -- Variable Star, database entry, SIMBAD. Accessed on line August 12, 2008.
2. ^ ^{a b c} NSV 414, database entry, table of suspected variable stars, Combined General Catalog of Variable Stars (GCVS4.2, 2004 Ed.), N. N. Samus, O. V. Durlevich, et al., CDS ID II/250.
3. ^ ^{a b c} HR 337, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line August 12, 2008.
4. ^ From apparent magnitude and parallax.
5. ^ ^{a b c d} Mirach, Stars, Jim Kaler. Accessed on line August 13, 2008.
6. ^ ^{a b c d e f g} Richard Hinckley Allen (1899) Star-names and Their Meanings, p. 36.
7. ^ Mirach's Ghost (NGC 404), The Internet Encyclopedia of Science, David Darling. Accessed on line August 15, 2008.
8. ^ p. 18, The Geography of the Heavens, Elijah Hinsdale Burritt, Hiram Mattison, and Henry Whitall, New York: Sheldon & Company, 1856.
9. ^ Mirach, MSN Encarta. Accessed on line August 19, 2008. Archived 2009-10-31.
10. ^ ^{a b c} George A.Davis Jr. (1971) Selected List of Star Names, p. 5.
11. ^ ibid. p. 19.
12. ^ Kunitsch, P., Smart, T., (2006) A Dictionary of Modern Star names: A Shoert Guide to 254 Star Names and Their Derivations, Cambridge, Sky Publishing Corp., p. 50.
13. ^ (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 978-986-7332-25-7.
14. ^ (Chinese) 香港太空館 - 研究資源 - 亮星中英對照表, Hong Kong Space Museum. Accessed on line November 23, 2010.
15. ^ p. 345, Exploring Ancient Skies: A Survey of Ancient and Cultural Astronomy, David H. Kelley, Eugene F. Milone, Anthony F. (FRW) Aveni, Berlin, Springer, 2011.
16. ^ Rogers, J. H. (February 1998). "Origins of the ancient constellations: I. The Mesopotamian traditions". Journal of the British Astronomical Association, no.1 108: 9–28. Bibcode 1998JBAA..108....9R. 

Further reading and external links

• Allen, R. H., (1899) Star Names and Their Meanings, New York: G. E. Stechert
• Davis Jr., G. A., (1971) Pronunciations, Derivations, and Meanings of a Selected List of Star Names, (rep.) Cambridge, Sky Publishing Corp.
• Kunitzsch, P., (1959) Arabische Sternnamen in Europa
• Kunitzsch. P., (ed.) (1990) Der Sternkatalog des Almagest, Band II
• http://www.astro.uiuc.edu/~kaler/sow/andromeda-p.html
• Image MIRACH
• Beta Andromedae on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

Coordinates: 01^h 09^m 43.9236^s, +35° 37′ 14.008″