HD 155448

Last updated
HD 155448
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Scorpius [1]
Right ascension 17h 12m 58.7680s [2]
Declination −32° 14 33.5690 [2]
Apparent magnitude  (V)8.72 [3]
Characteristics
HD 155448 A
Evolutionary stage Main sequence
Spectral type B1 V
B−V color index −0.27±0.02
HD 155448Ba
Evolutionary stage main sequence star
Spectral type B6V
B−V color index −0.15±0.02 [4]
HD 155448 Bb
Evolutionary stage main sequence star
Spectral type B9V [4]
B−V color index −0.08±0.02 [4]
HD 155448 C
Evolutionary stage Main sequence
Spectral type B4 Ve [4]
B−V color index −0.19±0.02 [4]
HD 155448 D
Evolutionary stage Main sequence
Spectral type B8 V [4]
B−V color index −0.11±0.02 [4]
Astrometry
A
Proper motion (μ)RA: +2.551 [5] mas/yr [5]
Dec.: –1.666 [5] mas/yr [5]
Parallax (π)0.9566±0.0440  mas
Distance 3,400 ± 200  ly
(1,050 ± 50  pc)
B
Proper motion (μ)RA: +1.758 [6] mas/yr [6]
Dec.: −1.520 [6] mas/yr [6]
Parallax (π)0.8401±0.0384  mas
Distance 3,900 ± 200  ly
(1,190 ± 50  pc)
D
Proper motion (μ)RA: +2.491 [7] mas/yr [7]
Dec.: −1.567 [7] mas/yr [7]
Parallax (π)0.7837±0.0263  mas
Distance 4,200 ± 100  ly
(1,280 ± 40  pc)
Details [4]
A
Mass >7  M
Surface gravity (log g)4  cgs
Temperature 25,000  K
Rotational velocity (v sin i)90±5 km/s
Ba
Mass 5  M
Surface gravity (log g)4  cgs
Temperature 14,000  K
Rotational velocity (v sin i)150±50 km/s
Bb
Mass 3  M
Surface gravity (log g)4  cgs
Temperature 10,000  K
Rotational velocity (v sin i)150±50 km/s
C
Mass 6  M
Surface gravity (log g)4  cgs
Temperature 16,000  K
Rotational velocity (v sin i)50±10 km/s
D
Mass 3.5  M
Surface gravity (log g)4  cgs
Temperature 12,000  K
Rotational velocity (v sin i)300±15 km/s
Other designations
CD−32°12461, HD 155448, HIP 84228, SAO 208540, WDS J17130-3215
Database references
SIMBAD data
B
C
D

HD 155448 is a quintuple star system consisting of 5 young B-type stars . With an apparent magnitude of 8.72, [3] it is too dim to be visible with the naked eye.

Parallax measurements from the Hipparcos spacecraft in 1997 give the system a distance of 1,976 light years with a margin of error larger than the parallax itself. [2] The New Hipparcos Reduction gives a distance of 6,272 light years, but still with a statistical margin of error larger than the parallax value. [8] Gaia parallaxes are available for the visible components. For component C, the Gaia Data Release 2 and Gaia Early Data Release 3 (EDR3) parallaxes are both negative and somewhat meaningless. [9] [7] For components A, B, and D, the Gaia EDR3 parallaxes are 0.9566±0.0440  mas , [5] 0.8401±0.0384  mas , [6] and 0.7837±0.0263  mas [7] respectively, implying a distance around 4,000 light years.

Before 2011, this star was mistaken as either a Herbig Ae/Be star [10] or a post-AGB object. [11] When the system was studied in 2011, it was originally believed to contain only 4 stars (or at least more than 2 stars). In 2011, a study conducted at the European Southern Observatory in Chile concluded that the "B" star is actually a binary star, thus reclassifying it as a quintuple star system. [4] HD 155448 A, B, C, and D. Periods have been estimated at 27,000 years for Bab, 59,000 years for AB, 111,000 years for Ac, and 327,000 years for AD. [12] However, analysis in 2011 states that the stars are not gravitationally bound to each other. [4]

All of the stars are currently on the ZAMS. At present the primary star has a mass greater than 7 solar masses and an effective temperature of 25,000 K, while the companions have masses ranging from 3-6 times the mass of the Sun, and temperatures ranging from 10,000-16,000 K.

References

  1. Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971 . Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015.
  2. 1 2 3 Perryman, M. A. C.; Lindegren, L.; Kovalevsky, J.; Hoeg, E.; Bastian, U.; Bernacca, P. L.; Crézé, M.; Donati, F.; Grenon, M.; Grewing, M.; van Leeuwen, F. (1997-07-01). "The HIPPARCOS Catalogue". Astronomy and Astrophysics. 323: L49 –L52. Bibcode:1997A&A...323L..49P. ISSN   0004-6361.
  3. 1 2 "HD 155448". sim-basic. Retrieved 21 March 2021.
  4. 1 2 3 4 5 6 7 8 9 10 Schütz, O.; Meeus, G.; Carmona, A.; Juhász, A.; Sterzik, M. F. (2011-09-01). "The young B-star quintuple system HD 155448". Astronomy and Astrophysics. 533: A54. arXiv: 1108.1557 . Bibcode:2011A&A...533A..54S. doi: 10.1051/0004-6361/201016396 . ISSN   0004-6361.
  5. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  6. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  7. 1 2 3 4 5 6 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  8. van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv: 0708.1752 . Bibcode:2007A&A...474..653V. doi: 10.1051/0004-6361:20078357 . ISSN   1432-0746.
  9. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
  10. Vioque, M.; Oudmaijer, R. D.; Baines, D.; Mendigutía, I.; Pérez-Martínez, R. (December 2018). "Gaia DR2 study of Herbig Ae/Be stars". Astronomy & Astrophysics. 620: A128. arXiv: 1808.00476 . Bibcode:2018A&A...620A.128V. doi: 10.1051/0004-6361/201832870 . ISSN   1432-0746.
  11. Luna, R.; Cox, N. L. J.; Satorre, M. A.; García Hernández, D. A.; Suárez, O.; García Lario, P. (March 2008). "A search for diffuse bands in the circumstellar envelopes of post-AGB stars". Astronomy & Astrophysics. 480 (1): 133–148. arXiv: 0711.1843 . Bibcode:2008A&A...480..133L. doi: 10.1051/0004-6361:20065282 . ISSN   1432-0746.
  12. Tokovinin, Andrei (2018-03-01). "The Updated Multiple Star Catalog". The Astrophysical Journal Supplement Series . 235 (1): 6. arXiv: 1712.04750 . Bibcode:2018ApJS..235....6T. doi: 10.3847/1538-4365/aaa1a5 . ISSN   0067-0049. S2CID   119047709.