Iota Trianguli

Iota Trianguli
Location of ι Trianguli (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Triangulum
A
Right ascension 02h 12m 22.2797s[1]
Declination +30° 18′ 11.053″[1]
Apparent magnitude (V) 5.32[2]
B
Right ascension 02h 12m 22.5637s[3]
Declination +30° 18′ 12.342″[3]
Apparent magnitude (V) 6.83[2]
Characteristics
A
Spectral type G0 III + G5 III[4]
B−V color index +0.856[5]
Variable type ellipsoidal + RS CVn[6]
B
Spectral type F5V + ?[2]
B−V color index +0.515[5]
Astrometry
A
Proper motion (μ) RA: −64.350[1] mas/yr
Dec.: −59.503[1] mas/yr
Parallax (π)11.3011 ± 0.1024 mas[1]
Distance289 ± 3 ly
(88.5 ± 0.8 pc)
B
Proper motion (μ) RA: −64.414[3] mas/yr
Dec.: −49.913[3] mas/yr
Parallax (π)12.7375 ± 0.5496 mas[3]
Distance260 ± 10 ly
(79 ± 3 pc)
Absolute magnitude (MV)+0.20[7]
Orbit[8]
PrimaryAa
CompanionAb
Period (P)14.73018 days
Semi-major axis (a)0.002[9]″
Eccentricity (e)0.0035
Inclination (i)55 – 58[9]°
Semi-amplitude (K1)
(primary)		54.84 km/s
Semi-amplitude (K2)
(secondary)		56.39 km/s
Orbit[10]
PrimaryBa
CompanionBb
Period (P)2.2365 days
Eccentricity (e)0
Semi-amplitude (K1)
(primary)		95.4 km/s
Semi-amplitude (K2)
(secondary)		101.0 km/s
Details
Aa
Mass2.50[9] M☉
Radius4.0[8] R☉
Luminosity61.7[8] L☉
Temperature4,932[8] K
Rotational velocity (v sin i)32.9[8] km/s
Ab
Mass2.43[9] M☉
Radius1.5[8] R☉
Luminosity10.0[8] L☉
Temperature6,486[8] K
Rotational velocity (v sin i)3.0[8] km/s
Ba
Mass1.58[9] M☉
Bb
Mass1.56[9] M☉
Other designations
TZ Tri, ι Tri, 6 Tri, BD+29°371, HD 13480, HIP 10280, HR 642, SAO 55347, WDS J02124+3018[11]
Database references
SIMBADdata

Iota Trianguli, Latinized from ι Trianguli, is a quadruple[2] star system in constellation of Triangulum. The pair have a combined apparent magnitude of 4.95[12] and are approximately 290 light years from Earth.

A light curve for Iota Trianguli, plotted from Hipparcos data[13]

Both components of ι Trianguli are spectroscopic binaries and the brighter pair is variable. It has been given the variable star designation TZ Trianguli. The variations are due to the ellipsoidal shape of the stars as they rotate, and also it is classified as an RS Canum Venaticorum variable.[14]

Together with 10 Trianguli and 12 Trianguli, it forms part of the obsolete Triangulum Minus.

  1. ^ a b c d e Cite error: The named reference dr3a was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference dr3b was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference aj1_74_916 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference myers2006 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference gcvs was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b c d e f g h i Cite error: The named reference massarotti2008 was invoked but never defined (see the help page).
  9. ^ a b c d e f Cite error: The named reference msc was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference luyten1936 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Rakos1982 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference HIPCurve was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Hall1980 was invoked but never defined (see the help page).