AK Pictoris

AK Pictoris is a star system in the constellation Pictor. Its combined apparent magnitude is 6.182.^[3] Based on the system's parallax, it is located 69 light-years (21.3 parsecs) away.^[2] AK Pictoris is a member of the AB Doradus moving group,^[10] a group of stars with similar motions that are thought to be associated.

AK Pictoris

A light curve for AK Pictoris, plotted from TESS data.[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Pictor
Right ascension	06h 38m 00.36576s[2]
Declination	−61° 32′ 00.1941″[2]
Apparent magnitude (V)	6.182[3] (6.32 / 8.77)[4]
Characteristics
Spectral type	G2 + K5:[5]
B−V color index	+0.62[6]
Variable type	BY Dra[7]
Astrometry
Radial velocity (Rv)	32.10 ± 0.5[8] km/s
Proper motion (μ)	RA: -47.84[2] mas/yr Dec.: 72.73[2] mas/yr
Parallax (π)	46.96 ± 0.81 mas[2]
Distance	69 ± 1 ly (21.3 ± 0.4 pc)
Absolute magnitude (MV)	4.63[9] + ?
Orbit[4]
Period (P)	217.6 yr
Semi-major axis (a)	2.004″
Eccentricity (e)	0.336
Inclination (i)	93.9°
Longitude of the node (Ω)	91.6°
Periastron epoch (T)	2033.9
Argument of periastron (ω) (secondary)	357.3°
Details
AK Pic A
Mass	1.03[10] M☉
Radius	1.22[10] R☉
Luminosity	1.45[10] L☉
Temperature	5860[5] K
Rotational velocity (v sin i)	15.1 ± 0.8[9] km/s
AK Pic B
Luminosity	0.25[5] L☉
Temperature	4400[5] K
Rotational velocity (v sin i)	15.5 ± 2.0[9] km/s
Other designations
CD−61° 1428, GJ 3400, HD 48189, HIP 31711, HR 2468, SAO 249604[3]
Database references
SIMBAD	data

AK Pictoris is a binary star. Its two stars orbit each other every 217.6 years, separated by 2.004″.^[4] The primary star is a G-type star^[5] with similar properties to the Sun. The secondary star is a K-type star.^[5] The primary star is a young BY Draconis variable,^[7] a class of variable stars that derive their variability from stellar rotation. It is also known to host a debris disk, inferred from its infrared excess.^[10]

References

1. "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 7 September 2024.
2. van Leeuwen, F.; et al. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Archived from the original on 2019-12-07. Retrieved 2017-07-20.
3. "V* AK Pic". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 20 July 2017.
4. "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 1 August 2017. Retrieved 20 July 2017.
5. McCarthy, Kyle; White, Russel J. (2012). "The Sizes of the Nearest Young Stars". The Astronomical Journal. 143 (6): 134. arXiv:1201.6600. Bibcode:2012AJ....143..134M. doi:10.1088/0004-6256/143/6/134. S2CID 118538522.
6. Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
7. Samus', N. N.; Goranskii, V. P.; Durlevich, O. V.; Zharova, A. V.; Kazarovets, E. V.; Kireeva, N. N.; Pastukhova, E. N.; Williams, D. B.; Hazen, M. L. (2003). "An Electronic Version of the Second Volume of the General Catalogue of Variable Stars with Improved Coordinates". Astronomy Letters. 29 (7): 468. Bibcode:2003AstL...29..468S. doi:10.1134/1.1589864. S2CID 16299532.
8. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
9. Fuhrmann, K.; Chini, R. (2015). "Multiplicity Among F-Type Stars. II". The Astrophysical Journal. 809 (1): 107. Bibcode:2015ApJ...809..107F. doi:10.1088/0004-637X/809/1/107. S2CID 126218052.
10. Plavchan, Peter; Werner, M. W.; Chen, C. H.; Stapelfeldt, K. R.; Su, K. Y. L.; Stauffer, J. R.; Song, I. (2009). "New Debris Disks Around Young, Low-Mass Stars Discovered with Thespitzer Space Telescope". The Astrophysical Journal. 698 (2): 1068–1094. arXiv:0904.0819. Bibcode:2009ApJ...698.1068P. doi:10.1088/0004-637X/698/2/1068. S2CID 51417657.