15 Andromedae

15 Andromedae

A light curve for V340 Andromedae, plotted from TESS data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Andromeda
Right ascension 23h 34m 37.53652s[2]
Declination +40° 14′ 11.1795″[2]
Apparent magnitude (V) 5.55[3]
Characteristics
Spectral type A1 III,[4] A1 Va,[5] or kA1hA3mA0.5 Va+.[6]
U−B color index 0.08
B−V color index 0.096±0.005[3]
Variable type δ Sct[7]
Astrometry
Radial velocity (Rv)13.1±0.6[3] km/s
Proper motion (μ) RA: -18.165 mas/yr
Dec.: −46.183[2] mas/yr
Parallax (π)12.9406 ± 0.0973 mas[2]
Distance252 ± 2 ly
(77.3 ± 0.6 pc)
Absolute magnitude (MV)+1.16±0.16[8]
Details[4]
Mass2.7 M☉
Luminosity27 L☉
Surface gravity (log g)3.90±0.03[8] cgs
Temperature9,225 K
Rotational velocity (v sin i)105[8] km/s
Age130 Myr
Other designations
15 And, V340 And, BD+39° 5114, FK5 1616, HD 221756, HIP 116354, HR 8947, SAO 73346, PPM 64401[9]
Database references
SIMBADdata

15 Andromedae, abbreviated 15 And, is a single,[10] variable star[7] in the northern constellation of Andromeda. 15 Andromedae is the Flamsteed designation, while its variable star designation is V340 And.[9] Its apparent visual magnitude is 5.55,[3] which indicates it is faintly visible to the naked eye. Its estimated distance from the Earth is 252 light years, and it is moving further away with a heliocentric radial velocity of 13 km/s.[3]

Depending on the source, this star has been classified as a giant star with a stellar classification of A1 III,[4] an A-type main-sequence star with a class of A1 Va,[5] or a Lambda Boötis star with a class of kA1hA3mA0.5 Va+.[6] It is a Delta Scuti variable that changes in brightness by 0.03 magnitude.[7] Two variability cycles, with periods 0.0403 and 0.0449 days, have been observed, a common feature for Lambda Boötis stars.[11] The star is around 130[4] million years old and has a high rotation rate, showing a projected rotational velocity of 105 km/s.[8] It has 2.7 times the mass of the Sun and is radiating 27 times the Sun's luminosity from its photosphere at an effective temperature of 9,225 K.[4]

This system has an excess emission of infrared radiation that suggests the presence of an orbiting disk of dust at a distance of around 50 AU from the host star.[4]

  1. ^ Cite error: The named reference MAST was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b c d e f Cite error: The named reference apj663_1_365 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Paunzen2001 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Murphy2015 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference gcvs was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference Paunzen2002 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Dorokhova2008 was invoked but never defined (see the help page).