Scutum (constellation) explained

Scutum
Abbreviation:Sct
Genitive:Scuti
Pronounce:,
genitive
Symbolism:the Shield of John III Sobieski
Family:Hercules
Quadrant:SQ4
Areatotal:109
Arearank:84th
Numbermainstars:2
Numberbfstars:7
Numberstarsplanets:1
Numberbrightstars:0
Numbernearbystars:0
Brighteststarname:α Scuti
Starmagnitude:3.85
Neareststarname:LHS 3398
Stardistancely:41.54
Stardistancepc:12.74
Numbermessierobjects:2
Meteorshowers:June Scutids
Bordering:Aquila
Sagittarius
Serpens Cauda
Latmax:80
Latmin:90
Month:August

Scutum is a small constellation. Its name is Latin for shield, and it was originally named Scutum Sobiescianum by Johannes Hevelius in 1684. Located just south of the celestial equator, its four brightest stars form a narrow diamond shape. It is one of the 88 IAU designated constellations defined in 1922.

History

Scutum was named in 1684 by Polish astronomer Johannes Hevelius[1] (Jan Heweliusz), who originally named it Scutum Sobiescianum (Shield of Sobieski) to commemorate the victory of the Christian forces led by Polish King John III Sobieski (Jan III Sobieski) in the Battle of Vienna in 1683. Later, the name was shortened to Scutum.

Five bright stars of Scutum (α Sct, β Sct, δ Sct, ε Sct and η Sct) were previously known as 1, 6, 2, 3, and 9 Aquilae respectively.[2]

The constellation of Scutum was adopted by the International Astronomical Union in 1922 as one of the 88 constellations covering the entire sky, with the official abbreviation of "Sct".[3] The constellation boundaries are defined by a quadrilateral. In the equatorial coordinate system, the right ascension coordinates of these borders lie between and, while the declination coordinates are between −3.83° and −15.94°.[4]

Coincidentally, the Chinese also associated these stars with battle armor, incorporating them into the larger asterism known as Tien Pien, i.e., the Heavenly Casque (or Helmet).[5]

Features

Stars

See also: List of stars in Scutum. Scutum is not a bright constellation, with the brightest star, Alpha Scuti, being a K-type giant star[6] at magnitude 3.85. However, some stars are notable in the constellation. Beta Scuti is the second brightest at magnitude 4.22, followed by Delta Scuti at magnitude 4.72. It is also known as 6 Aquilae.[7] Beta Scuti is a binary system,[8] [9] with the primary with a spectral type similar to the Sun, although it is 1,270 times brighter. Delta Scuti is a bluish white giant star, which is now coming at the direction of the Solar System. Within 1.3 million years it will come as close to 10 light years from Earth, and will be much brighter than Sirius by that time.

UY Scuti is a red supergiant and is also one of the largest stars currently known with a radius over 900 times that of the Sun.[10] RSGC1-F01 is another red supergiant whose radius is over 1,450 times that of the Sun.[11] Scutum contains several clusters of supergiant stars, including RSGC1,[12] Stephenson 2[13] [14] and RSGC3.[15]

Deep sky objects

Although not a large constellation, Scutum contains several open clusters, as well as a globular cluster and a planetary nebula. The two best known deep sky objects in Scutum are M11 (the Wild Duck Cluster) and the open cluster M26 (NGC 6694). The globular cluster NGC 6712 and the planetary nebula IC 1295 can be found in the eastern part of the constellation, only 24 arcminutes apart.

The most prominent open cluster in Scutum is the Wild Duck Cluster, M11. It was named by William Henry Smyth in 1844 for its resemblance in the eyepiece to a flock of ducks in flight. The cluster, 6200 light-years from Earth and 20 light-years in diameter, contains approximately 3000 stars, making it a particularly rich cluster. It is around 220 million years old,[16] although some studies give older estimates. Estimates for the mass of the star cluster range from to .

Space exploration

The space probe Pioneer 11 is moving in the direction of this constellation. It will not near the closest star in this constellation for over a million years[17] at its present speed, by which time its batteries will be long dead.

See also

Sources

External links

Notes and References

  1. http://www.ianridpath.com/startales/scutum.html Star Tales ― Scutum
  2. Wagman . M. . Flamsteed's Missing Stars . Journal for the History of Astronomy . 3 . 18 . 212–213 . August 1987 . 1987JHA....18..209W . 10.1177/002182868701800305. 118445625 .
  3. Russell . Henry Norris . Henry Norris Russell . The New International Symbols for the Constellations . . 30 . 469 . 1922PA.....30..469R . 1922.
  4. Scutum, Constellation Boundary . The Constellations . . 3 September 2020 .
  5. Richard H. Allen (1899) Star Names and Their Meanings, p. 363
  6. 1989ApJS...71..245K . 10.1086/191373. The Perkins catalog of revised MK types for the cooler stars. The Astrophysical Journal Supplement Series. 71. 245. 1989. Keenan. Philip C.. McNeil. Raymond C..
  7. Wagman . M. . Flamsteed's Missing Stars . Journal for the History of Astronomy . 18 . 3 . 212 . August 1987 . 1987JHA....18..209W . 10.1177/002182868701800305. 118445625 .
  8. 2016ApJS..227....4H . Surveying the Bright Stars by Optical Interferometry. I. A Search for Multiplicity among Stars of Spectral Types F-K . Astrophysical Journal Supplement Series . 227 . 4 . 1 . Hutter . D. J.. Zavala . R. T. . Tycner . C. . Benson . J. A. . Hummel . C. A. . Sanborn . J. . Franz . O. G. . Johnston . K. J. . 2016 . 10.3847/0067-0049/227/1/4 . 1609.05254 . 118803592 . free .
  9. 2005AJ....129.1700P . The Fine Guidance Sensor Orbit of the G4 Bright Giant HD 173764 . Astronomical Journal . 129 . 3 . 1700 . Parsons . S. B.. Franz . O. G. . Wassermann . L. H.. 2005 . 10.1086/427853 . free .
  10. Healy . Sarah . Horiuchi . Shunsaku . Molla . Marta Colomer . Milisavljevic . Dan . Tseng . Jeff . Bergin . Faith . Weil . Kathryn . Tanaka . Masaomi . 2024-03-23 . Red Supergiant Candidates for Multimessenger Monitoring of the Next Galactic Supernova . Monthly Notices of the Royal Astronomical Society . 529 . 4 . 3630–3650 . 10.1093/mnras/stae738 . free . 2307.08785 . 2024MNRAS.529.3630H . 0035-8711.
  11. Decin . Leen . Richards . Anita M. S. . Marchant . Pablo . Sana . Hugues . January 2024 . ALMA detection of CO rotational line emission in red supergiant stars of the massive young star cluster RSGC1 -- Determination of a new mass-loss rate prescription for red supergiants . Astronomy & Astrophysics . 681 . A17 . 10.1051/0004-6361/202244635 . 2303.09385 . 2024A&A...681A..17D . 0004-6361.
  12. Figer . D. F. . MacKenty . J. W. . Robberto . M. . Smith . K. . Najarro . F. . Kudritzki . R. P. . Herrero . A. . 10.1086/503275 . Discovery of an Extraordinarily Massive Cluster of Red Supergiants . The Astrophysical Journal . 643 . 2 . 1166–1179 . 2006 . astro-ph/0602146 . 2006ApJ...643.1166F . 18241900 .
  13. Davies . B. . Figer . D. F. . Kudritzki . R. P. . MacKenty . J. . Najarro . F. . Herrero . A. . 10.1086/522224 . A Massive Cluster of Red Supergiants at the Base of the Scutum-Crux Arm . The Astrophysical Journal . 671 . 1 . 781–801 . 2007 . 2007ApJ...671..781D. 0708.0821. 1447781 .
  14. 1990 . 1990AJ.....99.1867S . 1867 . 99 . 10.1086/115464 . A possible new and very remote galactic cluster . The Astronomical Journal . Stephenson . C. B..
  15. 513 . Astronomy and Astrophysics . Another cluster of red supergiants close to RSGC1 . A74 . 2010. 2010A&A...513A..74N . 10.1051/0004-6361/200913373 . S. . Martínez-Núñez . C. . González-Fernández . I. . Marco . A. . J. S. . Clark . Negueruela. 1002.1823 . 118531372 .
  16. So, Where Are the Wild Ducks?! . MacRobert . Alan . Sky and Telescope . September 2012.
  17. Pioneer 11 is travelling at ~2.4 au/yr, 41.54 ly ≈ 2.627x106au.