LP 145-141

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LP 145-141
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Musca[1]
Right ascension 11h 45m 42.9205s[2]
Declination −64° 50′ 29.459″[2]
Apparent magnitude (V) 11.50[2]
Characteristics
Spectral type DQ6[3]
U−B color index -0.59[2]
B−V color index +0.19[2]
Astrometry
Proper motion (μ) RA: 2665.25[2] mas/yr
Dec.: -346.19[2] mas/yr
Parallax (π) 215.80 ± 1.25[4] mas
Distance 15.11 ± 0.09 ly
(4.63 ± 0.03 pc)
Details
Mass 0.75 ± 0.03[5] M
Luminosity 0.0005[5] L
Surface gravity (log g) 8.27 ± 0.05[5] cgs
Temperature 8,500 ± 300[5] K
Age (as white dwarf)[5]
1.44 Gyr
Other designations
Database references
SIMBAD data

LP 145-141 is a white dwarf located 15 light years from the Solar System.[15] According to a 2009 paper, it is the fourth closest known white dwarf to the Sun (after Sirius B, Procyon B, and van Maanen's star.)[16]

History of observations[edit]

LP 145-141 is known at least from 1917, when its proper motion was published by R. T. A. Innes and H. E. Wood in Volume 37 of Circular of the Union Observatory.[14] The corresponding designation is UO 37.[6] (Note: this designation is not unique for this star, that is all other stars, listed in the table in the Volume 37 of this Circular, also could be called by this name).

Space motion[edit]

LP 145-141 may be a member of the Wolf 219 moving group, which has seven possible members. These stars share a similar motion through space, which may indicate a common origin.[17] This group has an estimated space velocity of 160 km/s and is following a highly eccentric orbit through the Milky Way galaxy.[18]

Properties[edit]

White dwarfs are no longer generating energy at their cores through nuclear fusion, and instead are steadily radiating away their remaining heat. LP 145-141 has a DQ spectral classification, indicating that it is a rare type of white dwarf which displays evidence of atomic or molecular carbon in its spectrum.[19]

LP 145-141 has only 75% of the Sun's mass, but it is the remnant of a massive main-sequence star that had an estimated 4.4 solar masses.[20] While it was on the main sequence, it probably was a spectral class B star (in the range B4-B9).[21] Most of the star's original mass was shed after it passed into the asymptotic giant branch stage, just prior to becoming a white dwarf.

Search for companions[edit]

A survey with the Hubble Space Telescope revealed no visible orbiting companions, at least down to the limit of detection.[3]

Its proximity, mass and temperature have led to it being considered a good candidate to look for Jupiter-like planets. Its relatively large mass and high temperature mean that the system is relatively short-lived and hence of more recent origin.[22]

References[edit]

  1. ^ "Constellation boundaries". Centre de Données astronomiques de Strasbourg. Retrieved 2007-07-16. 
  2. ^ a b c d e f g "SIMBAD query result: GJ 440 -- White Dwarf". Centre de Données astronomiques de Strasbourg. Retrieved 2007-07-16. 
  3. ^ a b Daniel J. Schroeder; et al. (February 2000). "A Search for Faint Companions to Nearby Stars Using the Wide Field Planetary Camera 2". The Astronomical Journal. 119 (2): 906–922. Bibcode:2000AJ....119..906S. doi:10.1086/301227. 
  4. ^ Subasavage, J. P.; Jao, W. C.; Henry, T. J.; Bergeron, P.; Dufour, P.; Ianna, P. A.; Costa, E.; Méndez, R. A. (2009). "The Solar Neighborhood. XXI. Parallax Results from the CTIOPI 0.9 m Program: 20 New Members of the 25 Parsec White Dwarf Sample". The Astronomical Journal. 137 (6): 4547–4560. arXiv:0902.0627Freely accessible. Bibcode:2009AJ....137.4547S. doi:10.1088/0004-6256/137/6/4547. 
  5. ^ a b c d e Table 2, P. Bergeron; S. K. Leggett; María Teresa Ruiz (April 2001). "Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax Measurements". Astrophysical Journal Supplement Series. 133 (2): 413–449. arXiv:astro-ph/0011286Freely accessible. Bibcode:2001ApJS..133..413B. doi:10.1086/320356. 
  6. ^ a b Porter, J. G.; Yowell, E. J.; Smith, E. S. (1930). "A catalogue of 1474 stars with proper motion exceeding four-tenths year.". Publications of the Cincinnati Observatory. 20: 1–32. Bibcode:1930PCinO..20....1P.  Page 16 (Ci 20 658).
  7. ^ Gliese, W.; Jahreiß, H. (1991). "Gl 440". Preliminary Version of the Third Catalogue of Nearby Stars. 
  8. ^ Perryman; et al. (1997). "HIP 57367". The Hipparcos and Tycho Catalogues. 
  9. ^ Luyten, Willem Jacob (1979). "LHS 30". LHS Catalogue, 2nd Edition. 
  10. ^ Luyten, Willem Jacob (1979). "NLTT 28447". NLTT Catalogue. 
  11. ^ Van Altena W. F.; Lee J. T.; Hoffleit E. D. (1995). "GCTP 2716". The General Catalogue of Trigonometric Stellar Parallaxes (Fourth ed.). 
  12. ^ Perryman; et al. (1997). "HIP 57367". The Hipparcos and Tycho Catalogues. 
  13. ^ Hog; et al. (2000). "TYC 8981-4417-1". The Tycho-2 Catalogue. 
  14. ^ a b Innes & Wood (1917). Page 290 (see string 41).
  15. ^ Henry, Todd J.; Walkowicz, Lucianne M.; Barto, Todd C.; Golimowski, David A. (April 2002). "The Solar Neighborhood. VI. New Southern Nearby Stars Identified by Optical Spectroscopy". The Astronomical Journal. 123 (4): 2002–2009. arXiv:astro-ph/0112496Freely accessible. Bibcode:2002AJ....123.2002H. doi:10.1086/339315. 
  16. ^ Table 1, "The White Dwarfs Within 20 Parsecs of the Sun: Kinematics and Statistics", Edward M. Sion et al., The Astronomical Journal 138, #6 (December 2009), pp. 1681-1689, doi:10.1088/0004-6256/138/6/1681, Bibcode2009AJ....138.1681S.
  17. ^ Eggen, O. J.; Greenstein, J. L. (1965). "Spectra, colors, luminosities, and motions of the white dwarfs". Astrophysical Journal. 141: 83–108. Bibcode:1965ApJ...141...83E. doi:10.1086/148091.  — see table 5.
  18. ^ Bell, R. A. (1962). "Observations of some southern white dwarfs". The Observatory. 82: 68–71. Bibcode:1962Obs....82...68B. 
  19. ^ Kawaler, S.; Dahlstrom, M. (2000). "White Dwarf Stars". American Scientist. 88 (6): 498. Bibcode:2000AmSci..88..498K. doi:10.1511/2000.6.498. Archived from the original on April 18, 2005. Retrieved 2007-07-19. 
  20. ^ Burleigh, M. R.; Clarke, F. J.; Hodgkin, S. T. (April 2002). "Imaging planets around nearby white dwarfs". Monthly Notices of the Royal Astronomical Society. 331 (4): L41–L45. arXiv:astro-ph/0202194Freely accessible. Bibcode:2002MNRAS.331L..41B. doi:10.1046/j.1365-8711.2002.05417.x. 
  21. ^ Siess, Lionel (2000). "Computation of Isochrones". Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles. Retrieved 2007-03-24. 
  22. ^ Burleigh, Matthew R.; Clarke, F.J.; Hodgkin, S.T. (2002). "Imaging Planets around Nearby White Dwarfs" (PDF). Monthly Notices of the Royal Astronomical Society. 331 (4): L41–L45. arXiv:astro-ph/0202194Freely accessible. Bibcode:2002MNRAS.331L..41B. doi:10.1046/j.1365-8711.2002.05417.x. 

External links[edit]