| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 16m 39.69960s[1] |
| Declination | −03° 39′ 05.7770″[1] |
| Apparent magnitude (V) | 4.46[2] |
| Characteristics | |
| Spectral type | A7 IVn[3] |
| U−B color index | +0.10[2] |
| B−V color index | +0.22[2] |
| Astrometry | |
| Radial velocity (Rv) | −3.0[4] km/s |
| Proper motion (μ) | RA: −110.37[1] mas/yr Dec.: −37.16[1] mas/yr |
| Parallax (π) | 17.71 ± 0.25 mas[1] |
| Distance | 184 ± 3 ly (56.5 ± 0.8 pc) |
| Absolute magnitude (MV) | 0.56[5] |
| Details | |
| Mass | 1.59[6] M☉ |
| Radius | 2.9[7] R☉ |
| Luminosity | 39[8] L☉ |
| Surface gravity (log g) | 3.56[3] cgs |
| Temperature | 7,680±261[3] K |
| Rotational velocity (v sin i) | 254[3] km/s |
| Age | 432[3] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Phi Leonis (φ Leo) is a single[10] star in the constellation Leo. It is bright enough to be seen with the naked eye, having an apparent visual magnitude of 4.46.[2] Based upon parallax measurements,[1] the distance to Phi Leo is around 184 light years.
The spectrum of this star fits a stellar classification of A7IVn,[3] which suggests it is an A-type subgiant star that has left the main sequence and is evolving into a giant star. It is being viewed with the plane of the star's equator lying close the line of sight from the Earth,[11] and shows a high rotation rate with a projected rotational velocity of 254 km/s.[3] This rapid spin is giving the star an oblate shape with an equatorial bulge that is 29% larger than the polar radius.[12]
Phi Leonis has been mentioned as a shell star—indicating that there is a circumstellar disk of gas around the star's equator—and may display a slight variability.[5] Sporadic variation of the spectra on the time scale of minutes up to months in duration suggests that solid, cometary bodies are in orbit around the star, with objects approaching close enough for refractory materials to sublimate.[11] Most exocomet hosts do have a circumstellar disk, which can act as an exocomet reservoir. Cold dust around Phi Leonis was not detected, and the star is not associated with a warm debris disk.[13]
- ^ a b c d e f Cite error: The named reference
vanLeeuwen2007was invoked but never defined (see the help page). - ^ a b c d Cite error: The named reference
Mermilliod1986was invoked but never defined (see the help page). - ^ a b c d e f g Cite error: The named reference
Royer2007was invoked but never defined (see the help page). - ^ Cite error: The named reference
Wielen1999was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
aaa354_157was invoked but never defined (see the help page). - ^ Cite error: The named reference
David2015was invoked but never defined (see the help page). - ^ Cite error: The named reference
cadarswas invoked but never defined (see the help page). - ^ Cite error: The named reference
Mcdonald2012was invoked but never defined (see the help page). - ^ Cite error: The named reference
SIMBADwas invoked but never defined (see the help page). - ^ Cite error: The named reference
Hutterwas invoked but never defined (see the help page). - ^ a b Cite error: The named reference
Eiroawas invoked but never defined (see the help page). - ^ Cite error: The named reference
aar20_1_51was invoked but never defined (see the help page). - ^ Cataldi, Gianni; Moór, Attila; Ohashi, Nagayoshi; Eiroa, Carlos; Grady, Carol; Rebollido, Isabel (2019-02-22). "No Detection of Cold Dust around the Potential Exocomet Host ϕ Leo". Research Notes of the AAS. 3 (2): 39. Bibcode:2019RNAAS...3...39C. doi:10.3847/2515-5172/ab082b. ISSN 2515-5172. S2CID 127680980.