18386+1632 HO 87 AB (HD 172246)

18h 38m 36.74s +16° 32' 27.7" P.A. 96.00 sep 0.4 mag 8.34,8.98 Sp G5 dist. 128.7 pc (419.82 l.y.)

Coord 2000 18386+1632 Discov num HO   87 Comp AB Coord arcsec 2000 18 38 36.74 +16 32 27.7
Date first 1883 Date last 2019 Obs 115
Pa first 259 Pa last 95.6 P.A. Now (θ) 99.5°
Sep first 0.3 Sep last 0.45 Sep. Now (ρ) 0.446"
Mag pri 8.34 Mag sec 8.98 delta mag (ΔM) 0.64 Spectral class G5 (yellow)
Pri motion ra -051 Sec motion ra
Pri motion dec -063 Sec motion dec
Notes N O (See Notes, Orbital solution)




This double is physical.



18386+1632 SYSTEM COMPONENTS

Show name SAO coord wds_name last obs pa sep mag1 mag2 d_mag orb current
Show HD 172246 103945 18 38 37 +16 32 28 HO 87 AB 2019 115 96 0.4 8.34 8.98 0.64 Y <===
Show 103945 18 38 37 +16 32 28 HO 87 AC 2015 9 121 47.3 8.34 14.17 5.83


Triple system
3 estimated visually detectable stars in this system



OTHER CATALOGS AND DESIGNATIONS

Name HD 172246 Constellation Hercules SAO 103945 HIP 91413
Tycho2 1570-02103-1 Gaia DR2 4511604454282166912 HD 172246 ADS 11530
BD BD+16 3572 Distance 128.7 Distance ly 419.82




ORBITAL ELEMENTS

Period (P)119.39y Periastron (T)1972.37y Semi-major axis (a)0.299a
Eccentricity (e)0.599 Inclination (i)19.6° Longitude of periastron (ω)78.8°
Node (Ω)210.5° Notesn ReferenceMsn2019
Equinox2000 Last observation2019 Grade2(1=Definitive, 9=Indet.)

label theta rho
2000 71.9 0.363
2001 73.4 0.369
2002 74.9 0.375
2003 76.3 0.381
2004 77.7 0.386
2005 79.1 0.391
2006 80.4 0.396
2007 81.6 0.400
2008 82.9 0.405
2009 84.1 0.409
2010 85.3 0.413
2011 86.5 0.416
2012 87.7 0.420
2013 88.8 0.423
2014 90.0 0.426
2015 91.1 0.429
2016 92.2 0.432
2017 93.2 0.435
2018 94.3 0.437
2019 95.4 0.439
2020 96.4 0.441
2021 97.5 0.443
2022 98.5 0.445
2023 99.5 0.446
2024 100.5 0.447
2025 101.6 0.448
2026 102.6 0.449
2027 103.6 0.450
2028 104.6 0.451
2029 105.6 0.451
2030 106.6 0.451


 
grafico orbita
Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.



 
 


wds18386%2B1632b.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic