Trumpler 16 (Tr 16) is a massive open cluster that is home to some of the most luminous stars in the Milky Way galaxy. It is situated within the Carina Nebula complex in the Carina–Sagittarius Arm, located approximately 9,270 ly (2,842 pc) from Earth.[1] The cluster has one star visible to the naked eye from the tropics southward, Eta Carinae.

Trumpler 16
The inner region of the Carina Nebula as seen in near-infrared. Trumpler 16 is the cluster of stars at the left, around Eta Carinae (the brightest star in the image).
Observation data (J2000 epoch)
Right ascension10h 45m 10s[1]
Declination−59° 43′ 00″[1]
Distance9,270 ly (2,842 pc)[1]
Apparent magnitude (V)5.0[1]
Physical characteristics
Other designationsCr 234, C 1043-863, Cl VDBH 105, OCl 829.0, [KPR2004b] 265, [KPS2012] MWSC 1850[1]
Associations
ConstellationCarina
See also: Open cluster, List of open clusters

Description

edit

Its most luminous members are Eta Carinae and WR 25, with both having luminosities several million times that of the Sun, and there are three other extreme stars with O3 spectral classes.[2] Both Eta Carinae and WR 25 are binaries, with the primary stars contributing most of the luminosity, but with companions which are themselves more massive and luminous than most stars. Totalling all wavelengths, Eta Carinae is estimated to be the more luminous of the two, 4,600,000 times the Sun's luminosity (absolute bolometric magnitude −12) compared to WR 25 at 2,400,000 times the Sun's luminosity (absolute bolometric magnitude −11.2). However, Eta Carinae appears by far the brightest object, both because it is brighter in visual wavelengths and because it is embedded in nebulosity which exaggerates the luminosity. WR 25 is very hot and emits most of its radiation at ultraviolet wavelengths.

Prominent stars
Star name MJ number Effective temperature (K) Absolute magnitude Bolometric magnitude Mass (M) Spectral type Ref.
η Car (HD 93308) 35200 37200 −8.6 −12 100 30 LBV O [3][4][5]
WR 25 (HD 93162) 245 50100 −6.98 −11.2 98 O2.5If*/WN6 OB [6][7]
HD 93250 383 46000 −6.14 −10.5 83 O4IV(fc) [8][9]
V560 Car (HD 93205) 342 51300 38000 −5.87 −4.32 −10.4 −7.9 40 17 O3.5Vf O8V [10][11][7]
HD 303308 480 51300 −5.9 −10.4 93 O3V [12]
HD 93204 340 46100 −5.4 −9.6 59 O5V [12]
CPD-59 2600 380 43600 −5.5 −9.6 55 O6V [12]
CPD-59 2641 535 43600 −5.2 −9.3 49 O6V [12]
ALS 15210 257 47800 −4.3 −8.7 44 O4I [12]
CPD-59 2603 408 41000 −5.2 −9.1 43 O7V [12]
CPD-59 2636 517 38500 −5.2 −8.9 37 O8V [12]
CPD-59 2626 484 41000 −4.8 −8.7 37 O7V [12]
HD 93343 512 41000 −4.7 −8.6 37 O7V [12]
V731 Car (CPD-59 2635) 516 37200 −5 −8.6 33 O8.5V [12]
CPD-59 2591 359 38500 −4 −7.7 27 O8V [12]
HD 305518 117 34700 −4.8 −8.2 27 O9.5V [12]

Carina OB1

edit

Trumpler 16 and Trumpler 14 are the most prominent star clusters in Carina OB1, a giant stellar association in the Carina spiral arm. Another cluster within Carina OB1, Collinder 228, is thought to be an extension of Trumpler 16 appearing visually separated only because of an intervening dust lane. The spectral types of the stars indicate that Trumpler 16 formed by a single wave of star formation. Because of the extreme luminosity of the stars formed, their stellar winds push away the clouds of dust, similar to the Pleiades. In a few million years, after the brightest stars have exploded as supernovae, the cluster will slowly die away. Trumpler 16 includes most of the stars in the eastern portion of the Carina OB1 association.[13]

Gaia Data Release 2

edit

Gaia Data Release 2 provides parallaxes for many stars considered to be members of Trumpler 16. It finds that the four hottest O-class stars in the region have very similar parallaxes with a mean value of 0.383±0.017 mas. Many of the other supposed members show significantly different parallaxes and may be foreground or background objects. Therefore, the distance of Trumpler 16 is assumed to be around 2,600 pc, significantly further than the accurately-known distance of η Carinae.[14]

edit

See also

edit

References

edit
  1. ^ a b c d e f "Trumpler 16". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2 December 2016.
  2. ^ Wolk, Scott J.; Broos, Patrick S.; Getman, Konstantin V.; Feigelson, Eric D.; Preibisch, Thomas; et al. (May 2011). "The Chandra Carina Complex Project View of Trumpler 16". The Astrophysical Journal Supplement. 194 (1). 12. arXiv:1103.1126. Bibcode:2011ApJS..194...12W. doi:10.1088/0067-0049/194/1/12. S2CID 13951142.
  3. ^ Groh, Jose H.; Hillier, D. John; Madura, Thomas I.; Weigelt, Gerd (2012). "On the influence of the companion star in Eta Carinae: 2D radiative transfer modelling of the ultraviolet and optical spectra". Monthly Notices of the Royal Astronomical Society. 423 (2): 1623. arXiv:1204.1963. Bibcode:2012MNRAS.423.1623G. doi:10.1111/j.1365-2966.2012.20984.x. S2CID 119205238.
  4. ^ Smith, Nathan; Frew, David J. (2011). "A revised historical light curve of Eta Carinae and the timing of close periastron encounters". Monthly Notices of the Royal Astronomical Society. 415 (3): 2009–19. arXiv:1010.3719. Bibcode:2011MNRAS.415.2009S. doi:10.1111/j.1365-2966.2011.18993.x. S2CID 118614725.
  5. ^ Mehner, A.; De Wit, W.-J.; Asmus, D.; Morris, P. W.; Agliozzo, C.; Barlow, M. J.; Gull, T. R.; Hillier, D. J.; Weigelt, G. (2019). "Mid-infrared evolution of η Carinae from 1968 to 2018". Astronomy & Astrophysics. 630: L6. arXiv:1908.09154. Bibcode:2019A&A...630L...6M. doi:10.1051/0004-6361/201936277. S2CID 202149820.
  6. ^ Sota, A.; Maíz Apellániz, J.; Morrell, N. I.; Barbá, R. H.; Walborn, N. R.; Gamen, R. C.; Arias, J. I.; Alfaro, E. J.; Oskinova, L. M. (2019). "The Galactic WN stars revisited. Impact of Gaia distances on fundamental stellar parameters". Astronomy & Astrophysics. A57: 625. arXiv:1904.04687. Bibcode:2019A&A...625A..57H. doi:10.1051/0004-6361/201834850. S2CID 104292503.
  7. ^ a b Sota, A.; Maíz Apellániz, J.; Morrell, N. I.; Barbá, R. H.; Walborn, N. R.; Gamen, R. C.; Arias, J. I.; Alfaro, E. J. (2014). "The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars". The Astrophysical Journal Supplement. 211 (1): 10. arXiv:1312.6222. Bibcode:2014ApJS..211...10S. doi:10.1088/0067-0049/211/1/10. S2CID 118847528.
  8. ^ Repolust, T.; Puls, J.; Herrero, A. (2004). "Stellar and wind parameters of Galactic O-stars. The influence of line-blocking/blanketing". Astronomy and Astrophysics. 415: 349. Bibcode:2004A&A...415..349R. doi:10.1051/0004-6361:20034863.
  9. ^ Maíz Apellániz, J.; Sota, A.; Arias, J. I.; Barbá, R. H.; Walborn, N. R.; Simón-Díaz, S.; Negueruela, I.; Marco, A.; Leão, J. R. S.; Herrero, A.; Gamen, R. C.; Alfaro, E. J. (2016). "The Galactic O-Star Spectroscopic Survey (GOSSS). III. 142 Additional O-type Systems". The Astrophysical Journal Supplement Series. 224 (1): 4. arXiv:1602.01336. Bibcode:2016ApJS..224....4M. doi:10.3847/0067-0049/224/1/4. S2CID 55658165.
  10. ^ Morrell, N. I.; Barbá, R. H.; Niemela, V. S.; Corti, M. A.; Albacete Colombo, J. F.; Rauw, G.; Corcoran, M.; Morel, T.; Bertrand, J.-F.; Moffat, A. F. J.; St-Louis, N. (2001). "Optical spectroscopy of X-Mega targets - II. The massive double-lined O-type binary HD 93205" (PDF). Monthly Notices of the Royal Astronomical Society. 326 (1): 85–94. arXiv:astro-ph/0105014. Bibcode:2001MNRAS.326...85M. doi:10.1046/j.1365-8711.2001.04500.x. S2CID 16221731.
  11. ^ Benvenuto, O. G.; Serenelli, A. M.; Althaus, L. G.; Barbá, R. H.; Morrell, N. I. (2002). "Calculation of the masses of the binary star HD 93205 by application of the theory of apsidal motion". Monthly Notices of the Royal Astronomical Society. 330 (2): 435–442. arXiv:astro-ph/0110662. Bibcode:2002MNRAS.330..435B. doi:10.1046/j.1365-8711.2002.05083.x. S2CID 16834579.
  12. ^ a b c d e f g h i j k l Massey, P.; Degioia-Eastwood, K.; Waterhouse, E. (2001). "The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. II. Results from 12 Galactic Clusters and OB Associations". The Astronomical Journal. 121 (2): 1050–1070. arXiv:astro-ph/0010654. Bibcode:2001AJ....121.1050M. doi:10.1086/318769. S2CID 53345173.
  13. ^ Carraro, G.; Romaniello, M.; Ventura, P.; Patat, F. (May 2004). "The star cluster Collinder 232 in the Carina complex and its relation to Trumpler 14/16". Astronomy and Astrophysics. 418 (2): 525–537. arXiv:astro-ph/0401144. Bibcode:2004A&A...418..525C. doi:10.1051/0004-6361:20034335. S2CID 17507621.
  14. ^ Davidson, Kris; Helmel, Greta; Humphreys, Roberta M. (2018). "Gaia, Trumpler 16, and Eta Carinae". Research Notes of the American Astronomical Society. 2 (3): 133. arXiv:1808.02073. Bibcode:2018RNAAS...2..133D. doi:10.3847/2515-5172/aad63c. S2CID 119030757.

Further reading

edit
edit