Y Cygni

Short description: Binary star in the constellation Cygnus

Not to be confused with Upsilon Cygni.

Y Cyg

A light curve for Y Cygni, plotted from TESS data[1]

Observation data
Equinox J2000.0]] (ICRS)
Constellation | Cygnus
Right ascension |  20h 52m 3.57718s[2]
Declination | +34° 39′ 27.4861″[2]
Apparent magnitude (V) | 7.3 - 7.9[3]
Characteristics
Primary
Spectral type | O9.5V[4]
Apparent magnitude (U) | 5.91[citation needed]
Apparent magnitude (B) | 6.996[citation needed]
Apparent magnitude (V) | 7.287[4]
U−B color index | −1.086[4]
B−V color index | −0.291[4]
Secondary
Spectral type | O9.5V[4]
Apparent magnitude (U) | 5.883[citation needed]
Apparent magnitude (B) | 6.974[citation needed]
Apparent magnitude (V) | 7.265[4]
U−B color index | −1.091[4]
B−V color index | −0.291[4]
Variable type | Algol[3]
Astrometry
Proper motion (μ)|  RA: +2.763[2] mas/yr
Dec.: −15.981[2] mas/yr
Parallax (π)| 0.6759 ± 0.0338[2] mas
Distance| 4,900 ly
(1,500[4] pc)
Absolute magnitude (MV)| −3.59/−3.62[4]
Absolute bolometric
magnitude (Mbol)| −6.65±0.04/−6.7±0.04[4]
Orbit[4]
Primary| Y Cyg A
Companion| Y Cyg B
Period (P)| 2.99633210±0.00000031 d
Semi-major axis (a)| 28.72 R☉
Eccentricity (e)| 0.14508
Inclination (i)| 86.474±0.019°
Periastron epoch (T)| 2,446,308.66407±0.0001
Argument of periastron (ω)
(secondary)| 312.514°
Argument of periapsis (ω)
(primary)| 132.514±0.052°
Details[4]
Primary
Mass| 17.72±0.35 M☉
Radius| 5.785±0.091 R☉
Luminosity| 36,000 L☉
Surface gravity (log g)| 4.161±0.014 cgs
Temperature| 33,200±200 K
Rotational velocity (v sin i)| 132 km/s
Age| 2 Myr
Secondary
Mass| 17.73±0.3 M☉
Radius| 5.816±0.063 R☉
Luminosity| 37,700 L☉
Surface gravity (log g)| 4.157±0.01 cgs
Temperature| 33,521±40 K
Rotational velocity (v sin i)| 132 km/s
Age| 2 Myr
Other designations

Y Cyg, HD 198846, HIP 102999

Database references
SIMBAD| data

Y Cygni is an eclipsing and double-lined spectroscopic binary star system in the constellation of Cygnus. It is located about 4,900 light-years from Earth. The system was one of the first binaries with a convincing detection of the apsidal precession.[4]

The two stars, being O-type main-sequence stars, orbit each other with a period of nearly 3 days.[4]

## Observation history

The early type of Y Cyg made it a popular target for astronomers in the past, and spectroscopic orbits have been historically computed numerous times.[5] The first of these studies was published in 1920 by John Stanley Plaskett.[6] Extensive spectroscopic studies of Y Cyg were carried out as early as 1930.[7] Several follow-ups to these have been published in 1959,[8] 1971,[9][10] and 1980.[11] The latter of these contained an estimate of the period of apsidal precession.

## References

1. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html.
2. ↑ 2.0 2.1 2.2 2.3 2.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
3. ↑ 3.0 3.1 Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1: B/gcvs. Bibcode: 2009yCat....102025S.
4. ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 Harmanec, P.; Holmgren, D. E.; Wolf, M.; Božić, H.; Guinan, E. F.; Kang, Y. W.; Mayer, P.; McCook, G. P. et al. (March 2014). "Revised physical elements of the astrophysically important O9.5+O9.5V eclipsing binary system Y Cygni". Astronomy and Astrophysics 563: A120. doi:10.1051/0004-6361/201323230. ISSN 0004-6361. Bibcode: 2014A&A...563A.120H.
5. ↑ Hill, G.; Holmgren, D. E. (May 1995). "Studies of early-type variable stars. IX. Y Cygni.". Astronomy and Astrophysics 297: 127–134. Bibcode: 1995A&A...297..127H.
6. ↑ Jones, Harold Spencer (1 November 1942). "John Stanley Plaskett, 1865-1941". The Royal Society 4 (11): 67–82. doi:10.1098/rsbm.1942.0007.
7. ↑ Redman, R. O. (August 1930). "Y Cygni.". The Astronomical Society of the Pacific 42: 250. doi:10.1086/124047. Bibcode: 1930PASP...42..250R.
8. ↑ Struve, O.; Sahade, J.; Zabergs, V. (January 1959). "Y Cygni.". Astrophysical Journal 129: 59. doi:10.1086/146595. Bibcode: 1959ApJ...129...59S.
9. ↑ Vitrichenko, E. A. (1971). "The improvement of the Spectroscopic orbit of Y Cyg.". Società Astronomia Italiana 43: 71. Bibcode: 1972MmSAI..43...71V.
10. ↑ Vitrichenko, E. A. (1971). "The improvement of the Spectroscopic orbit of Y Cyg.". Izv. Krym. Astrofiz. Obs. 43: 71–75. Bibcode: 1971IzKry..43...71V.
11. ↑ Gimenez, A.; Costa, V. (December 1980). "Y CYG : photometry and apsidal motion.". The Astronomical Society of the Pacific 92: 782–784. doi:10.1086/130747. Bibcode: 1980PASP...92..782G.

* v
* t
* e

Constellation of Cygnus

* List of stars in Cygnus

Stars|

| Bayer|

* α (Deneb)
* β (Albireo)
* γ (Sadr)
* δ (Fawaris)
* ε (Aljanah)
* ζ
* η
* θ
* ι1
* ι2
* κ
* λ
* μ
* ν
* ξ
* π1 (Azelfafage)
* π2
* ρ
* σ
* τ
* υ
* φ
* χ
* ψ
* ω1
* ω2
* P
* Q

|

Flamsteed|

* 2
* 4
* 8
* 9
* 14
* 15
* 16 (c)
* 17
* 20 (d)
* 22
* 23
* 26 (e)
* 27 (b1)
* 28 (b2)
* 29 (b3)
* 30
* 31
* 32
* 33
* 35
* 39
* 41
* 47
* 52
* 55
* 56
* 57
* 59 (f1)
* 61
* 63 (f2)
* 68 (A)
* 71 (g)
* 72
* 74
* 75

Variable|

* R
* T
* W
* RW
* SS
* TT
* BC
* BI
* CH
* KY
* V404
* V476
* V1057
* V1143
* V1191
* V1489
* V1500
* V1668
* V1974
* V2513

HR|

* 7633
* 7912
* 8193

HD|

* 185269
* 185435
* 187123
* 188753
* 191806

Gliese|

* 777
* 806
* 1245

Kepler|

* 5
* 6
* 11
* 15
* 16
* 17
* 18
* 22
* 23
* 27
* 28
* 29
* 31
* 32
* 33
* 34
* 35
* 36
* 39
* 40
* 41
* 42
* 43
* 44
* 45
* 47
* 51
* 56
* 61
* 66
* 67
* 68
* 69
* 70
* 78
* 80
* 84
* 86
* 89
* 107
* 182
* 186
* 223
* 371
* 419
* 432
* 451
* 452
* 1229
* 1520
* 1625

Other|

* AFGL 2591
* BD+40° 4210
* BD+43 3654
* Cygnus OB2 #8A
* Cygnus OB2 #12
* Cygnus X-1
* Cygnus X-3
* G 208-44
* G 208-45
* HAT-P-7
* HAT-P-11
* HAT-P-17
* KELT-9
* KIC 8462852
* KIC 9832227
* KIC 11026764
* KOI-74
* KOI-81
* KOI-256
* KPD 1930+2752
* MWC 349
* N6946-BH1
* NML Cygni
* PH1
* PSR J2032+4127
* W75N(B)-VLA2
* WISE J2000+3629
* WR 134
* WR 135
* WR 136
* WR 137
* WR 140
* WR 142
* WR 147
* WR 148

Former|

* 3

Star
clusters|

| Association|

* Cygnus OB2
* Cygnus OB7

|

Open|

* DR 6
* IC 5146
* Messier 29
* Messier 39
* NGC 6811
* NGC 6819
* NGC 6834
* NGC 6866
* NGC 6871
* NGC 6910

Molecular
clouds|

* Cygnus X (including DR 21)

Nebulae|

| Dark|

* Barnard 146
* Barnard 147
* IC 5146
* L1014

|

H II|

* NGC 6914
* North America Nebula
* Pelican Nebula
* Sadr Region
* Sh2-101
* Sh2-106

Planetary|

* Abell 78
* Egg Nebula
* IRAS 19475+3119
* Kronberger 61
* M1-92
* NGC 6826
* NGC 6881
* NGC 6884
* NGC 7008
* NGC 7026
* NGC 7027
* NGC 7048
* Soap Bubble Nebula

WR|

* Crescent Nebula

SNR|

* Cygnus Loop (including Veil Nebula)

Galaxies|

| NGC|

* 6801
* 6946
* 7013

|

Other|

* 3C 438
* Cygnus A

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/Y Cygni. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:Y_Cygni&oldid=2574029"
*[RA:]: Right Ascension
*[Dec.:]: Declination
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template