13 Sagittae

13 Sagittae

A visual band light curve for VZ Sagittae, plotted from data published by Tabur et al. (2009)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Sagitta
Right ascension 20h 00m 03.30846s[2]
Declination +17° 30′ 59.4373″[2]
Apparent magnitude (V) 5.33[1]
Characteristics
Spectral type M4 III[1]
B−V color index 1.576±0.010[3]
Variable type semiregular[4]
Astrometry
Radial velocity (Rv)−17.56±0.33[5] km/s
Proper motion (μ) RA: +1.75[2] mas/yr
Dec.: −12.41[2] mas/yr
Parallax (π)3.20 ± 0.31 mas[2]
Distance1,020 ± 100 ly
(310 ± 30 pc)
Absolute magnitude (MV)−2.12[3]
Details
Radius185.7[6] R☉
Luminosity2173.57[3] L☉
Surface gravity (log g)3.00[7] cgs
Temperature3,844±251[8] K
Other designations
13 Sge, VZ Sge, BD+17° 4183, HD 189577, HIP 98438, HR 7645, SAO 105522, WDS J20001+1731C[9]
Database references
SIMBADdata

13 Sagittae is a single[10] star in the northern constellation of Sagitta. The designation comes from the star catalogue of John Flamsteed, first published in 1712. It can be viewed with the naked eye, having an apparent visual magnitude of 5.33.[1] Based upon an annual parallax shift of 3.20 mas as seen from Earth's orbit, it is located at a distance of around 310 parsecs (1,000 ly). It is moving closer to the Sun with a heliocentric radial velocity of −17.56 km/s.[5]

Pulsation Cycles[1]
Period
(days) 		Amplitude
(magnitude)
36.5 0.082
39.2 0.043
51.4 0.031
65.2 0.030

This is an evolved red giant with a stellar classification of M4 III[1] – a star that has used up its core hydrogen and has expanded – and is currently on the asymptotic giant branch.[7] Classified as a semiregular variable and given the variable star designation VZ Sagittae, it varies between apparent magnitudes 5.27 and 5.57.[4] Il has expanded to around 186 times the Sun's radius.[6]

There is a magnitude 9.96 companion located at an angular separation of 112.6 arcseconds along a position angle of 297°, as of 2013.[11] Designated HD 351107, this is a class F0 star.[12]

  1. ^ a b c d e f Cite error: The named reference Tabur2009 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference AAVSO was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Famaey2005 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference ortiz2016 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Soubiran2010 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Mason2014 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Nesterov1995 was invoked but never defined (see the help page).