Pi Canis Majoris
Pi Canis Majoris (π Canis Majoris; Latin for 'Greater Dog') is a binary star[9] system in the southern constellation of Canis Major. It is visible to the naked eye, having an apparent visual magnitude of +4.69.[2] Based upon an annual parallax shift of 33.80 mas as seen from Earth,[1] this system is located 96.5 light years from the Sun. The star is moving in the general direction of the Sun with a radial velocity of −37.9 km/s. It will make its closest approach in around 733,000 years when it comes within 23 ly (7 pc).[4]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h 55m 37.43099s[1] |
| Declination | −20° 08′ 11.3902″[1] |
| Apparent magnitude (V) | +4.69[2] |
| Characteristics | |
| Spectral type | F1.5 V[3] |
| U−B color index | +0.06[2] |
| B−V color index | +0.36[2] |
| Astrometry | |
| Radial velocity (Rv) | −37.9±5.5[4] km/s |
| Proper motion (μ) | RA: +51.50[1] mas/yr Dec.: +39.58[1] mas/yr |
| Parallax (π) | 33.80 ± 0.24 mas[1] |
| Distance | 96.5 ± 0.7 ly (29.6 ± 0.2 pc) |
| Absolute magnitude (MV) | +2.06[5] |
| Details | |
| π CMa A | |
| Mass | 1.32[6] M☉ |
| Luminosity | 9[7] L☉ |
| Surface gravity (log g) | 3.91[6] cgs |
| Temperature | 6,863±233[6] K |
| Metallicity [Fe/H] | −0.18[3] dex |
| Rotational velocity (v sin i) | 91.7±4.6[5] km/s |
| Age | 763[6] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The brighter primary, component A, is an F-type main-sequence star with a stellar classification of F1.5 V.[3] It is a periodic variable star with a frequency of 11.09569 cycles per day (2.16 hours per cycle) and an amplitude of 0.0025 in magnitude.[10] The star has an estimated 1.32[6] times the mass of the Sun and is radiating nine[7] times the Sun's luminosity from its photosphere at an effective temperature of around 6,863 K.[6] It displays a strong infrared excess at a wavelength of 24 μm and a weaker excess at 70 μm, indicating the presence of a circumstellar disk of dust with a temperature of 188 K, orbiting at 6.7 AU from the host star.[11]
The magnitude 9.6 companion, component B, lies at an angular separation of 11.6 arc seconds from the primary as of 2008.[9] Their projected separation is about 339 AU.[11]
In popular culture edit
This star is the origin of the alien crystal, and the destination of starship Salvare, on Netflix show Another Life.
See also edit
References edit
- ^ a b c d e f van Leeuwen, F. (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.
- ^ a b c d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
- ^ a b c Gray, R. O.; et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ a b Bailer-Jones, C. A. L. (March 2015), "Close encounters of the stellar kind", Astronomy & Astrophysics, 575: 13, arXiv:1412.3648, Bibcode:2015A&A...575A..35B, doi:10.1051/0004-6361/201425221, S2CID 59039482, A35.
- ^ a b Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv:astro-ph/0509399, Bibcode:2006A&A...446..267R, doi:10.1051/0004-6361:20053911, S2CID 8642707
- ^ a b c d e f David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ a b McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ "pi. CMa". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-09-03.
{{cite web}}: CS1 maint: postscript (link) - ^ a b Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Koen, Chris; Eyer, Laurent (2002), "New periodic variables from the Hipparcos epoch photometry", Monthly Notices of the Royal Astronomical Society, 331 (1): 45–59, arXiv:astro-ph/0112194, Bibcode:2002MNRAS.331...45K, doi:10.1046/j.1365-8711.2002.05150.x, S2CID 10505995.
- ^ a b Trilling, D. E.; et al. (April 2007), "Debris disks in main-sequence binary systems", The Astrophysical Journal, 658 (2): 1264–1288, arXiv:astro-ph/0612029, Bibcode:2007ApJ...658.1289T, doi:10.1086/511668, S2CID 14867168.