Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Serpens |
Right ascension | 15h 36m 28.1827s [2] |
Declination | +15° 06′ 05.240″ [2] |
Apparent magnitude (V) | 5.89 to 7.07 [3] |
Characteristics | |
Spectral type | M5IIIa [4] |
B−V color index | 1.2 [5] |
Variable type | SRB [3] |
Astrometry | |
Radial velocity (Rv) | −26±5 [5] km/s |
Proper motion (μ) |
RA: −3.623
[2]
mas/
yr Dec.: +4.476 [2] mas/ yr |
Parallax (π) | 4.5628 ± 0.2728 mas [2] |
Distance | 710 ± 40
ly (220 ± 10 pc) |
Absolute magnitude (MV) | −0.03 [6] |
Details | |
Mass | 3.9 [7] M☉ |
Radius | 239 [8] R☉ |
Luminosity | 4,969 [8] L☉ |
Surface gravity (log g) | −0.14 [7] cgs |
Temperature | 3,178 [7] K |
Metallicity [Fe/H] | +0.21 [7] dex |
Other designations | |
Database references | |
SIMBAD | data |
Tau4 Serpentis, Latinized from τ4 Serpentis, is a variable M-type giant star in the constellation of Serpens, approximately 710 light-years from the Earth. [5]
With a spectral classification M5IIIa, Tau4 Serpentis is a cool red giant star. The spectrum varies, [4] and some sources classify it between M4IIIe and M6IIIe. [9] Some of its spectral lines show an inverse P Cygni profile, [10] where cold infalling gas on to the star creates redshifted hydrogen absorption lines next to the normal emission lines. [11] It is classified as a semiregular late-type variable, and its magnitude varies between +5.89 and +7.07 with a period of approximately 100 days. [3]
τ4 is unique among the stars with the Bayer designation τ Serpentis as being the only one with no HR catalog number.
Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Serpens |
Right ascension | 15h 36m 28.1827s [2] |
Declination | +15° 06′ 05.240″ [2] |
Apparent magnitude (V) | 5.89 to 7.07 [3] |
Characteristics | |
Spectral type | M5IIIa [4] |
B−V color index | 1.2 [5] |
Variable type | SRB [3] |
Astrometry | |
Radial velocity (Rv) | −26±5 [5] km/s |
Proper motion (μ) |
RA: −3.623
[2]
mas/
yr Dec.: +4.476 [2] mas/ yr |
Parallax (π) | 4.5628 ± 0.2728 mas [2] |
Distance | 710 ± 40
ly (220 ± 10 pc) |
Absolute magnitude (MV) | −0.03 [6] |
Details | |
Mass | 3.9 [7] M☉ |
Radius | 239 [8] R☉ |
Luminosity | 4,969 [8] L☉ |
Surface gravity (log g) | −0.14 [7] cgs |
Temperature | 3,178 [7] K |
Metallicity [Fe/H] | +0.21 [7] dex |
Other designations | |
Database references | |
SIMBAD | data |
Tau4 Serpentis, Latinized from τ4 Serpentis, is a variable M-type giant star in the constellation of Serpens, approximately 710 light-years from the Earth. [5]
With a spectral classification M5IIIa, Tau4 Serpentis is a cool red giant star. The spectrum varies, [4] and some sources classify it between M4IIIe and M6IIIe. [9] Some of its spectral lines show an inverse P Cygni profile, [10] where cold infalling gas on to the star creates redshifted hydrogen absorption lines next to the normal emission lines. [11] It is classified as a semiregular late-type variable, and its magnitude varies between +5.89 and +7.07 with a period of approximately 100 days. [3]
τ4 is unique among the stars with the Bayer designation τ Serpentis as being the only one with no HR catalog number.