GK Tauri

Summary

Coordinates: Sky map 04h 33m 34.5627s, +24° 21′ 05.8545″

GK Tauri
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
GK Tauri
Right ascension 04h 33m 34.5627s[1]
Declination +24° 21′ 05.8545″[1]
Apparent magnitude (V) 15.10
GI Tauri
Right ascension 04h 33m 34.0609s[2]
Declination +24° 21′ 17.0674″[2]
Apparent magnitude (V)
Characteristics
GK Tauri
Evolutionary stage pre-main-sequence star
Spectral type K7[3]
Apparent magnitude (G) 11.990[1]
Variable type T Tau
GI Tauri
Apparent magnitude (G) 12.608[2]
Astrometry
GK Tauri
Proper motion (μ) RA: 7.46±0.02[1] mas/yr
Dec.: −20.510±0.017[1] mas/yr
Parallax (π)7.7433 ± 0.0185[1] mas
Distance421 ± 1 ly
(129.1 ± 0.3 pc)
GI Tauri
Proper motion (μ) RA: 5.76±0.02[2] mas/yr
Dec.: −20.642±0.019[2] mas/yr
Parallax (π)7.7258 ± 0.0198[2] mas
Distance422 ± 1 ly
(129.4 ± 0.3 pc)
Position (relative to GK Tauri)[4]
ComponentGI Tauri
Angular distance13.15797±0.00005
Position angle328.4399±0.0002°
Observed separation
(projected)
1700 AU
Details[4]
GK Tauri
Mass0.79±0.07 M
Luminosity0.80[5] L
Temperature4007[5] K
Age2±Myr
GI Tauri
Mass0.53+0.09
−0.11
 M
Luminosity0.49[5] L
Temperature3792[5] K
Age2±Myr
Other designations
GK Tauri: Gaia EDR3 147790206908395776, 2MASS J04333456+2421058, GSC 01829-00040
GI Tauri: Gaia EDR3 147790000749072768, 2MASS J04333405+2421170, GSC 01829-00082
Database references
SIMBADdata

GK Tauri is a young T Tauri-type pre-main sequence star in the constellation of Taurus about 421 light years away, belonging to the Taurus Molecular Cloud.

System

The stars GK Tauri and GI Tauri form a wide binary system, with the projected separation between components being 1700 AU. The secondary component's orbit is not very eccentric, with a periastron of at least 890 AU.[4]

GK Tauri was originally believed to have a close stellar companion WDS J04336+2421Ab.[6] However, it was found to be an unrelated background star according to Gaia data.[7]

Properties

Both members of the binary system are medium-mass objects still contracting towards the main sequence and accreting mass, with the primary GK Tauri being close to entering the main sequence.[3][4]

Protoplanetary system

Both stars are surrounded by compact protoplanetary disks, although the reason for the small disk sizes is not clear.[4] GK Tauri's spectrum indicates a possible gap in the protoplanetary disk and a planet orbiting within the gap, with a semimajor axis of 2.4+1.5
−1.0
AU.[3]

The GK Tauri planetary system[4]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
protoplanetary disk 0–19 AU 40.2+5.9
−6.2
°
The GI Tauri planetary system[4]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
protoplanetary disk 0–25 AU 43.8±1.1°

References

  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. Gaia EDR3 record for this source at VizieR.
  2. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. Gaia EDR3 record for this source at VizieR.
  3. ^ a b c Marsh, Kenneth A.; Mahoney, Michael J. (1993), "Do the Spectral Energy Distributions of GK Tauri and HK Tauri Indicate the Presence of Planetary Companions?", The Astrophysical Journal, 405: L71, Bibcode:1993ApJ...405L..71M, doi:10.1086/186768
  4. ^ a b c d e f g Pearce, Logan A.; Kraus, Adam L.; Dupuy, Trent J.; Mann, Andrew W.; Newton, Elisabeth R.; Tofflemire, Benjamin M.; Vanderburg, Andrew (2020), "Orbital Parameter Determination for Wide Stellar Binary Systems in the Age of Gaia", The Astrophysical Journal, 894 (2): 115, arXiv:2003.11106, Bibcode:2020ApJ...894..115P, doi:10.3847/1538-4357/ab8389
  5. ^ a b c d Braun, Teresa A. M.; Yen, Hsi-Wei; Koch, Patrick M.; Manara, Carlo F.; Miotello, Anna; Testi, Leonardo (2021), "Dynamical Stellar Masses of Pre-main-sequence Stars in Lupus and Taurus Obtained with ALMA Surveys in Comparison with Stellar Evolutionary Models", The Astrophysical Journal, 908 (1): 46, arXiv:2012.07441, Bibcode:2021ApJ...908...46B, doi:10.3847/1538-4357/abd24f, S2CID 229156020
  6. ^ "V* GK Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 18 June 2021.
  7. ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. Gaia EDR3 record for this source at VizieR.