HD 15115

HD 15115

Debris disk surrounding young star HD 15115
Credit: NASA, ESA, G. Schneider (University of Arizona), and the HST/GO 12228 Team
Observation data
Epoch J2000      Equinox J2000
Constellation Cetus
Right ascension 02h 26m 16.24577s[1]
Declination +06° 17′ 33.1880″[1]
Apparent magnitude (V) 6.76[2]
Characteristics
Spectral type F4IV[3] or F2V[4]
U−B color index −0.03[2]
B−V color index +0.39[2]
Astrometry
Radial velocity (Rv)0.81±0.12[5] km/s
Proper motion (μ) RA: +88.030[1] mas/yr
Dec.: -50.515[1] mas/yr
Parallax (π)20.4065 ± 0.0418 mas[1]
Distance159.8 ± 0.3 ly
(49.0 ± 0.1 pc)
Details
Mass1.19[6] M☉
Radius1.39±0.06[1] R☉
Luminosity3.74±0.01[1] L☉
Surface gravity (log g)4.30[6] cgs
Temperature6,811+148
−152[1] K
Metallicity [Fe/H]0.96[6] dex
Rotational velocity (v sin i)89.8[7] km/s
Age500[8] Myr
Other designations
BD+05°338, HD 15115, HIP 11360, SAO 110532, WDS J02263+0618A[9]
Database references
SIMBADdata

HD 15115 is a single[10] star in the equatorial constellation of Cetus. It is readily visible in binoculars or a small telescope, but is considered too dim to be seen with the naked eye at an apparent visual magnitude of 6.76.[2] The distance to this object is 160 light years based on parallax,[1] and it is slowly drifting further away at the rate of about 1 km/s.[5] It has been proposed as a member of the Beta Pictoris moving group[11] or the Tucana-Horologium association of co-moving stars; there is some ambiguity as to its true membership.[12]

This object has a stellar classification of F4IV,[3] suggesting it is an aging subgiant star that has exhausted the supply of hydrogen at its core. MacGregor and associates (2015) instead classify it as a young F-type main-sequence star with a class of F2V.[4] Age estimates give a value of 500[8] million years, while membership in the β Pictoris moving group would indicate an age of around 21±4 million.[4] It has 1.19[6] times the mass of the Sun, 1.39[1] times the Sun's radius, and has a relatively high rate of spin with a projected rotational velocity of 90 km/s.[7] The star is radiating 3.74[1] times the luminosity of the Sun from its photosphere at an effective temperature of 6,811 K.[1] Its metallicity – the abundance of elements other than hydrogen and helium – is nearly the same as in the Sun.[6]

HD 15115 was shown to have an asymmetric debris disk surrounding it, which is being viewed nearly edge-on. The reason for the asymmetry is thought to be either the gravitational pull of a passing star (HIP 12545), an exoplanet, or interaction with the local interstellar medium.[13] A magnitude 11.35 visual companion lies at an angular separation of 12.6″ along a position angle of 195°, as of 2015.[11]

  1. ^ a b c d e f g h i j k l Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference oja was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference harlan was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference MacGregor2015 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Desidera2015 was invoked but never defined (see the help page).
  6. ^ a b c d e Cite error: The named reference Luck2018 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Pribulla2014 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference apj598_1_636 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Rodriguez2012 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference AlonsoFloriano2015 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Malo2013 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Debes was invoked but never defined (see the help page).