WD J1953−1019 is a hierarchical triple system of white dwarfs located at about 130 parsecs (about 420 light years) from the Earth. This is the first triple system of white dwarfs to be resolved.[3][1] The three white dwarfs have an atmosphere of pure hydrogen and a mass of about 0.6 times that of the Sun.

WD J1953−1019

Pan-STARRS color composite image of the WD J1953−1019 system, with the three components annotated.[a]
Observation data
Epoch 2015.5      Equinox 2015.5
Constellation Aquila
Right ascension A: 19h 53m 33.11s
B: 19h 53m 35.99s
C: 19h 53m 36.02s
Declination A: −10° 19′ 55.10″
B: −10° 19′ 31.76″
C: −10° 19′ 29.49″
Characteristics
Evolutionary stage White dwarf
Spectral type DA
Apparent magnitude (V) 17.27 (A) · 16.05 (B) · 16.29 (C)
Apparent magnitude (G) 17.28 (A) · 16.35 (B) · 16.44 (C)
Apparent magnitude (B) 17.27 (A) · 16.05 (B) · 16.29 (C)
Apparent magnitude (R) 17.30 (A) · 16.30 (B) · 16.44 (C)
Apparent magnitude (g) 17.18 (A) · 16.15 (B) · 16.24 (C)
Astrometry
A
Proper motion (μ) RA: −10.81 ± 0.25 mas/yr
Dec.: −16.10 ± 0.15 mas/yr
Distance128.36 ± 2.40 pc
B
Proper motion (μ) RA: −11.54 ± 0.18 mas/yr
Dec.: −16.33 ± 0.11 mas/yr
Distance130.37 ± 2.11 pc
C
Proper motion (μ) RA: −10.94 ± 0.19 mas/yr
Dec.: −15.66 ± 0.12 mas/yr
Distance130.89 ± 2.01 pc
Details[1]
MassA: 0.63±0.03
B: 0.62±0.03
C: 0.60±0.03 M
TemperatureA: 13715±310
B: 22223±360
C: 22104±350 K
Other designations
A: Gaia DR2 4190500054845023488
B: Gaia DR2 4190499986125543168
C: Gaia DR2 4190499986125543296
Database references
A
SIMBADdata
B
SIMBADdata
C
SIMBADdata

The system consists of a central pair, WD J1953−1019 BC, and a distant companion, WD J1953−1019 A. WD J1953−1019 B and C correspond to the sources Gaia DR2 4190499986125543168[4] and 4190499986125543296[5] respectively. The white dwarfs of the central pair, WD J1953−1019 B and C, are separated 303.25±0.01 AU from each other while the distant companion, WD J1953−1019 A, orbits the barycenter, or center of mass, of the central binary at a distance of 6398.97±0.09 AU.[1]

The cooling age found by M. Perpinyà-Vallès and collaborators for the three white dwarfs is consistent, with an estimated value between 40 and 290 million years.[1] The three stars would each come from a star that had a mass between 1.6 and 2.6 times that of the Sun. A collision of the central pair due to Lidov-Kozai oscillations is unlikely as the system is dynamically stable.[1] However, if this collision occurred, it could produce a type Ia supernova below the Chandrasekhar mass.[1]

See also

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Notes

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  1. ^ The color composite consists of Pan-STARRS images taken in g, i, and y passband filters.[1] These filters correspond to specific wavelengths of 481 nm, 752 nm, and 962 nm, respectively.[2]

References

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  1. ^ a b c d e f g Perpinyà-Vallès, M.; Rebassa-Mansergas, A.; Gänsicke, B. T.; Toonen, S.; Hermes, J. J.; Gentile Fusillo, N. P.; Tremblay, P.-E. (February 2019). "Discovery of the first resolved triple white dwarf". Monthly Notices of the Royal Astronomical Society. 483 (1): 901–907. arXiv:1811.07752. Bibcode:2019MNRAS.483..901P. doi:10.1093/mnras/sty3149.
  2. ^ Tonry, J. L.; Stubbs, C. W.; Lykke, K. R.; Doherty, P.; Shiivers, I. S.; Gentile Fusillo, N. P.; et al. (May 2012). "The Pan-STARRS1 Photometric System". The Astrophysical Journal. 750 (2): 14. arXiv:1203.0297. Bibcode:2012ApJ...750...99T. doi:10.1088/0004-637X/750/2/99. S2CID 119266289. 99.
  3. ^ "A student at the UPC's Barcelona School of Telecommunications has discovered the first resolved triple white dwarf system ever reported". BarcelonaTech. Universitat Politècnica de Catalunya. 13 February 2019. Retrieved 7 May 2019.
  4. ^ "Gaia DR2 4190499986125543168 -- White Dwarf". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 7 May 2019.
  5. ^ "Gaia DR2 4190499986125543296 -- White Dwarf". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 7 May 2019.