NR Canis Majoris

NR Canis Majoris

A light curve for NR Canis Majoris, plotted from TESS data[1]
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]
Distance297 ± 2 ly
(91.2 ± 0.8 pc)
Absolute magnitude (MV)0.78[3]
Details
A
Mass1.62[7] or 2.18±0.04[8] M☉
Radius3.90+0.18
−0.24[2] R☉
Luminosity37.4±0.4[2] L☉
Surface gravity (log g)3.65[7] cgs
Temperature7,227+238
−160[2] K
Rotational velocity (v sin i)185[9] km/s
Age1.494[7] Gyr
Other designations
NR CMa, BD−17°1980, HD 58954, HIP 36186, HR 2853, SAO 152894, ADS 6093, CCDM J07271-1752AB, WDS J07271-1752[10]
Database references
SIMBADdata

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]

  1. ^ Cite error: The named reference MAST was invoked but never defined (see the help page).
  2. ^ a b c d e f g h i Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference David2015 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference zorec2012 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference vanBelle2012 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference BailerJones2015 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference tomkin1998 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference AAVSONR was invoked but never defined (see the help page).