TYC 9486-927-1

TYC 9486-927-1

A light curve for FT Octantis, plotted from TESS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Octans
Right ascension 21h 25m 27.4805s[2]
Declination −81° 38′ 27.692″[2]
Apparent magnitude (V) 11.5 - 12.0[3]
Characteristics
Spectral type M1 V[4]
Variable type BY Dra[3]
Astrometry
Radial velocity (Rv)8.7±4.6[4] km/s
Proper motion (μ) RA: 60.645(46) mas/yr[2]
Dec.: −107.740(48) mas/yr[2]
Parallax (π)29.0266 ± 0.0401 mas[2]
Distance112.4 ± 0.2 ly
(34.45 ± 0.05 pc)
Details
Mass0.53[5] M☉
Radius0.46[6] R☉
Luminosity0.032[6] L☉
Surface gravity (log g)4.3[7] cgs
Temperature3,490[8] K
Metallicity [Fe/H]−1.3[7] dex
Rotation0.541945[3] days
Rotational velocity (v sin i)43.5±1.2[8] km/s
Age10-45[8] Myr
Other designations
2MASS J21252752-8138278, FT Octantis
Database references
SIMBADdata

TYC 9486-927-1 (also known as 2MASS J21252752-8138278) is the primary of a possible trinary star system located at a distance of 34.5 parsecs from Earth in the southern direction in the constellation of Octans. It is a BY Draconis variable, with large starspots causing it to change brightness as it rotates every 13 hours.[3]

TYC 9486-927-1 has rapid rotation and coronal and chromospheric activity suggestive of a young age. Observations and multi-epoch radial velocity data suggest that TYC 9486-927-1 is a single, rapidly rotating star rather than a spectroscopic or tight visual binary. However, it is still possible that TYC 9486-927-1 is an equal mass binary with a face-on orbit and close separation.[4]

The candidate secondary stellar companion is 2MASS J21121598–8128452. It is a red dwarf star of spectral class M5.5. Its projected separation from the primary would be 62,700 AU. The candidate tertiary companion is 2MASS J21192028–8145446 - of spectral class M6 or M7 and at a projected separation of 31,000 AU from the primary.[5]: 7 

  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 Gaia DR3 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference gcvs was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference sacy was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Smart2019 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference conch was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference rave was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference deacon was invoked but never defined (see the help page).