| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 07h 27m 07.99012s [2] |
| Declination | −17° 51′ 53.5058″ [2] |
| Apparent magnitude (V) | 5.60 [3] (5.66 + 9.23) [4] |
| Characteristics | |
| Spectral type | F2V [5] |
| B−V color index | +0.314±0.002 [3] |
| Variable type | δ Sct [6] |
| Astrometry | |
| Radial velocity (Rv) | −29.2±2.9 [3] km/s |
| Proper motion (μ) |
RA: −2.420
[2]
mas/
yr Dec.: +1.388 [2] mas/ yr |
| Parallax (π) | 10.9688 ± 0.0917 mas [2] |
| Distance | 297 ± 2
ly (91.2 ± 0.8 pc) |
| Absolute magnitude (MV) | 0.78 [3] |
| Details | |
| A | |
| Mass | 1.62 [7] or 2.18±0.04 [8] M☉ |
| Radius | 3.90+0.18 −0.24 [2] R☉ |
| Luminosity | 37.4±0.4 [2] L☉ |
| Surface gravity (log g) | 3.65 [7] cgs |
| Temperature | 7,227+238 −160 [2] K |
| Rotational velocity (v sin i) | 185 [9] km/s |
| Age | 1.494 [7] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
NR Canis Majoris is a
binary star
[11] system in the southern
constellation of
Canis Major, located to the east of
Sirius and
Gamma Canis Majoris near the constellation border with
Puppis. It has a yellow-white hue and is dimly visible to the naked eye with a combined
apparent visual magnitude that fluctuates around 5.60.
[3] It is located at a distance of approximately 297
light years from the
Sun based on
parallax.
[2] The system is drifting closer to the Sun with a
radial velocity of −29 km/s,
[3] and in about three million years it is predicted to approach within 14.1+4.7
−4.0 ly.
[12] At that time, the star will become the
brightest in the night sky, potentially reaching magnitude −0.88.
[13]
The magnitude 5.66 [4] primary component is an F-type main-sequence star with a stellar classification of F2V. [5] It is a Delta Scuti variable [6] that varies by a few hundredths of a magnitude over roughly 16 hours. [14] The star is an estimated 1.5 billion years old. [7] It has a high rate of spin with a projected rotational velocity of 185 km/s, which is giving the star an equatorial bulge that is estimated to be 8% larger than the polar radius. [9]
The secondary companion is magnitude 9.23 and lies at an angular separation of 1.3 ″ along a position angle of 39°, as of 2005. [4]
References
- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
- ^ a b c d e f g h i Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e f Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971. Bibcode: 2012AstL...38..331A. doi: 10.1134/S1063773712050015. S2CID 119257644.
- ^ a b c Mason, B. D.; et al. (2014). "The Washington Visual Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode: 2001AJ....122.3466M. doi: 10.1086/323920. Retrieved 2015-07-22.
- ^ a b Houk, Nancy; Smith-Moore, M. (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 4. Ann Arbor: Department of Astronomy, University of Michigan. Bibcode: 1988mcts.book.....H.
- ^ a b Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode: 2017ARep...61...80S. doi: 10.1134/S1063772917010085. S2CID 125853869.
- ^ a b c d 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.
- ^ Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv: 1201.2052. Bibcode: 2012A&A...537A.120Z. doi: 10.1051/0004-6361/201117691. S2CID 55586789.
- ^ a b van Belle, Gerard T. (March 2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review. 20 (1): 51. arXiv: 1204.2572. Bibcode: 2012A&ARv..20...51V. doi: 10.1007/s00159-012-0051-2. S2CID 119273474.
- ^ "NR CMa". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 12 February 2017.
- ^ 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.
- ^ 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.
- ^ Tomkin, Jocelyn (April 1998). "Once and Future Celestial Kings". Sky and Telescope. 95 (4): 59–63. Bibcode: 1998S&T....95d..59T.
- ^ Watson, Christopher (4 January 2010). "LS Canis Majoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 12 July 2014.
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| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 07h 27m 07.99012s [2] |
| Declination | −17° 51′ 53.5058″ [2] |
| Apparent magnitude (V) | 5.60 [3] (5.66 + 9.23) [4] |
| Characteristics | |
| Spectral type | F2V [5] |
| B−V color index | +0.314±0.002 [3] |
| Variable type | δ Sct [6] |
| Astrometry | |
| Radial velocity (Rv) | −29.2±2.9 [3] km/s |
| Proper motion (μ) |
RA: −2.420
[2]
mas/
yr Dec.: +1.388 [2] mas/ yr |
| Parallax (π) | 10.9688 ± 0.0917 mas [2] |
| Distance | 297 ± 2
ly (91.2 ± 0.8 pc) |
| Absolute magnitude (MV) | 0.78 [3] |
| Details | |
| A | |
| Mass | 1.62 [7] or 2.18±0.04 [8] M☉ |
| Radius | 3.90+0.18 −0.24 [2] R☉ |
| Luminosity | 37.4±0.4 [2] L☉ |
| Surface gravity (log g) | 3.65 [7] cgs |
| Temperature | 7,227+238 −160 [2] K |
| Rotational velocity (v sin i) | 185 [9] km/s |
| Age | 1.494 [7] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
NR Canis Majoris is a
binary star
[11] system in the southern
constellation of
Canis Major, located to the east of
Sirius and
Gamma Canis Majoris near the constellation border with
Puppis. It has a yellow-white hue and is dimly visible to the naked eye with a combined
apparent visual magnitude that fluctuates around 5.60.
[3] It is located at a distance of approximately 297
light years from the
Sun based on
parallax.
[2] The system is drifting closer to the Sun with a
radial velocity of −29 km/s,
[3] and in about three million years it is predicted to approach within 14.1+4.7
−4.0 ly.
[12] At that time, the star will become the
brightest in the night sky, potentially reaching magnitude −0.88.
[13]
The magnitude 5.66 [4] primary component is an F-type main-sequence star with a stellar classification of F2V. [5] It is a Delta Scuti variable [6] that varies by a few hundredths of a magnitude over roughly 16 hours. [14] The star is an estimated 1.5 billion years old. [7] It has a high rate of spin with a projected rotational velocity of 185 km/s, which is giving the star an equatorial bulge that is estimated to be 8% larger than the polar radius. [9]
The secondary companion is magnitude 9.23 and lies at an angular separation of 1.3 ″ along a position angle of 39°, as of 2005. [4]
References
- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
- ^ a b c d e f g h i Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e f Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971. Bibcode: 2012AstL...38..331A. doi: 10.1134/S1063773712050015. S2CID 119257644.
- ^ a b c Mason, B. D.; et al. (2014). "The Washington Visual Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode: 2001AJ....122.3466M. doi: 10.1086/323920. Retrieved 2015-07-22.
- ^ a b Houk, Nancy; Smith-Moore, M. (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 4. Ann Arbor: Department of Astronomy, University of Michigan. Bibcode: 1988mcts.book.....H.
- ^ a b Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode: 2017ARep...61...80S. doi: 10.1134/S1063772917010085. S2CID 125853869.
- ^ a b c d 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.
- ^ Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv: 1201.2052. Bibcode: 2012A&A...537A.120Z. doi: 10.1051/0004-6361/201117691. S2CID 55586789.
- ^ a b van Belle, Gerard T. (March 2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review. 20 (1): 51. arXiv: 1204.2572. Bibcode: 2012A&ARv..20...51V. doi: 10.1007/s00159-012-0051-2. S2CID 119273474.
- ^ "NR CMa". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 12 February 2017.
- ^ 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.
- ^ 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.
- ^ Tomkin, Jocelyn (April 1998). "Once and Future Celestial Kings". Sky and Telescope. 95 (4): 59–63. Bibcode: 1998S&T....95d..59T.
- ^ Watson, Christopher (4 January 2010). "LS Canis Majoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 12 July 2014.
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Star clusters |
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