| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Canis Minor |
| Right ascension | 07h 24m 13.9974s [1] |
| Declination | +08° 53′ 51.787″ [1] |
| Apparent magnitude (V) | 9.7 - 10.6 [2] |
| Characteristics | |
| Red giant | |
| Evolutionary stage | AGB [3] |
| Spectral type | M4-M6 III [3] |
| Variable type | SRc [2] |
| Astrometry | |
| Radial velocity (Rv) | −4.89±0.55 [1] km/s |
| Proper motion (μ) | RA: −0.202 mas/yr [1] Dec.: −4.224 mas/yr [1] |
| Parallax (π) | 0.7644±0.0516 mas [1] |
| Distance | 4,050+310 −260 ly (1,241+94 −80 pc) [4] |
| Details | |
| Red giant | |
| Mass | 1.8–2.4±0.4 [3] M☉ |
| Radius | 231±16 [3] R☉ |
| Luminosity | 5,350±750 [3] L☉ |
| Temperature | 3,131±69 [5] K |
| White dwarf | |
| Mass | 1? [3] M☉ |
| Other designations | |
| ZZ CMi, BD+09°1633, HIP 35915, TIC 453173127, IRAS 07214+0859 [6] | |
| Database references | |
| SIMBAD | data |
ZZ Canis Minoris is a symbiotic binary [7] in the constellation Canis Minor. It is 4,000 light-years distant and is not visible to the naked eye with a maximum apparent magnitude of +9.7.
This binary system is made up of a red giant primary and a white dwarf secondary that is accreting material from the red giant. The accretion disk around the white dwarf and the collision of both components' stellar winds create X-ray emission. [7] It does not show any silicon oxide (SiO) masers, [8] nor an infrared excess that would identify it as a dusty symbiotic binary. [9] The orbital period of the system is tentatively inferred to be 983 days. [3]
The red giant primary is a semiregular variable, with an apparent magnitude that varies from 9.7 to 10.6 [2] over an uncertain period, values of 106 [2] and 437 days have been published. [11] It has over 230 times the Sun's radius and is 5,350 times as luminous, [3] radiating this energy from a cool, 3,200 K photosphere. [5] It is on the asymptotic giant branch stage of its evolution, and is likely filling its roche lobe. [3]