LP 658-2 explained

LP 658-2 is a degenerate (white dwarf) star in the constellation of Orion, the single known object in its system. It has an apparent visual magnitude of approximately 14.488.

Distance

According to a 2009 paper, it is the eighth closest known white dwarf to the Sun (after Sirius B, Procyon B, van Maanen's star, Gliese 440, 40 Eridani B, Stein 2051 B and GJ 1221).[1] Its trigonometric parallax from the CTIOPI (Cerro Tololo Inter-American Observatory (CTIO) Parallax Investigation) 0.9 m telescope program, published in 2009, is 0.15613 ± 0.00084 arcsec, corresponding to a distance 6.40 ± 0.03 pc, or 20.89 ± 0.11 ly. Also, previous less precise parallax measurements of LP 658-2 present in YPC (Yale Parallax Catalog) and among results of CTIOPI 1.5 m telescope program:

LP 658-2 parallax measurements

Source Paper Parallax, mas Distance, pc Distance, ly Ref.
YPC van Altena et al., 1995 155.0 ± 2.1 6.45 ± 0.09 21.04 ± 0.29
CTIOPI 1.5 m TSN-14 (Costa et al., 2005) 156.93 ± 2.67 6.37 ± 0.11 20.78 ± 0.35 [2]
CTIOPI 0.9 m TSN-21 (Subasavage et al., 2009) 156.13 ± 0.84 6.40 ± 0.03 20.89 ± 0.11

Physical parameters

There are two sets of published physical parameters of LP 658-2, significantly differing from each other: one from and, the other from .

Color

Despite it being classified as a "white" dwarf, it appears yellowish white rather than white, due to temperature, cooler than the Sun's and comparable with that of a K-type main sequence star.

Notes

  1. Table 1 in
  2. Costa . Edgardo . Méndez . René A. . Jao . W.-C. . Henry . Todd J. . Subasavage . John P. . Brown . Misty A. . Ianna . Philip A. . Bartlett . Jennifer. Jennifer Bartlett (astronomer) . The solar neighborhood. XIV. Parallaxes from the Cerro Tololo Inter-American Observatory Parallax Investigation—First results from the 1.5 m telescope program . The Astronomical Journal . July 2005 . 130 . 1 . 337–349 . 2005AJ....130..337C . 10.1086/430473. free .