T Carinae

This article is about the variable star. For t¹ Carinae, see HD 92063. For t² Carinae, see HD 92397.
T Carinae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Carina
Right ascension 10h 55m 17.22143s[1]
Declination −60° 31′ 01.1999″[1]
Apparent magnitude (V) 5.93[2]
Characteristics
Evolutionary stage Horizontal branch[3]
Spectral type K0III[4]
B−V color index +1.065±0.007[2]
Variable type Constant[5]
Astrometry
Radial velocity (Rv)−25.5±2.9[2] km/s
Proper motion (μ) RA: −34.858[1] mas/yr
Dec.: +85.164[1] mas/yr
Parallax (π)11.4593 ± 0.0762 mas[1]
Distance285 ± 2 ly
(87.3 ± 0.6 pc)
Absolute magnitude (MV)1.08[2]
Details
Radius9.25+0.21
−0.86[1] R☉
Luminosity38.6±0.3[1] L☉
Temperature4,729+237
−52[1] K
Other designations
T Car, CD−59°3419, CPD−59°2840, GC 15026, HD 94776, HIP 53394, HR 4271, SAO 251178[6]
Database references
SIMBADdata

T Carinae is a star in the southern constellation of Carina. Although given a variable star designation, it is now thought to be constant;[5] the identifier HD 94776 from the Henry Draper catalogue may be used instead. It has an orange hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.93.[2] The distance to this object is approximately 285 light years based on parallax,[1] and it has an absolute magnitude of 1.08.[2] It is drifting closer to the Sun with a radial velocity of −26 km/s.[2]

This is an aging giant star with a stellar classification of K0III,[4] which indicates it has exhausted the supply of hydrogen at its core and expanded off the main sequence. It is a red clump giant, which means it is on the horizontal branch and is undergoing core helium fusion.[3] At present it has nine times the Sun's radius and is radiating 39 times the luminosity of the Sun from its photosphere at an effective temperature of 4,729 K.[1]

When used as a comparison star for AG Carinae in 1914 by H. E. Wood,[7] this object was announced as a candidate variable star. A year later it was determined by R. Innis that it was AG Carinae that varied and this star is constant. Later, T Carinae became flagged as a low amplitude irregular variable.[8] It is now catalogued as a probable constant star.[5]

  1. ^ a b c d e f g h i j Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Laney2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Houk1979 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Wood1914 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Mayall1969 was invoked but never defined (see the help page).