| 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 | |
| NR CMa, BD−17°1980, HD 58954, HIP 36186, HR 2853, SAO 152894, ADS 6093, CCDM J07271-1752AB, WDS J07271-1752 [10] | |
| 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] The star was discovered to be a variable star when the Hipparcos data was analyzed. It was given its variable star designation, NR Canis Majoris, in 1999. [14] It is a Delta Scuti variable [6] that varies by a few hundredths of a magnitude over roughly 16 hours. [15] 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]
