18084+4407 HDS 2554 (HD 166409)

 
 
18h 08m 21.80s +44° 06' 45.1" P.A. 205.00 sep 0.1 mag 7.58,7.81 Sp F5 dist. 101.21 pc (330.15 l.y.)
 
 
Coord 2000 18084+4407 Discov num HDS2554 Comp Coord arcsec 2000 18 08 21.80 +44 06 45.1
Date first 1991 Date last 2013 Obs 10
Pa first 25 Pa last 204.7 P.A. Now (θ) 204.7°
Sep first 0.1 Sep last 0.135 Sep. Now (ρ) 0.135"
Mag pri 7.58 Mag sec 7.81 delta mag (ΔM) 0.23 Spectral class F5 (yellow-white)
Pri motion ra +021 Sec motion ra
Pri motion dec +025 Sec motion dec
Notes O (Orbital solution)
This double is physical.
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Name HD 166409 Constellation Hercules SAO 47250 HIP 88852
Tycho2 3114-01636-1 Gaia DR2 2115646434121439616 HD 166409 GC 24749
BD BD+44 2829 Distance 101.21 Distance ly 330.15
 
 
ORBITAL ELEMENTS
 
 
Period (P)21.6y± 0.7 Periastron (T)2001.4y± 0.7 Semi-major axis (a)111.8m± 3.1
Eccentricity (e)0.217± 0.033 Inclination (i)75.3°± 1.7 Longitude of periastron (ω)160°± 12
Node (Ω)208.3°± 1.7 Notes ReferenceHor2011b
Equinox2000 Last observation2008 Grade4(1=Definitive, 9=Indet.)
label theta rho
2000 7.5 0.054
2001 19.8 0.076
2002 27.2 0.088
2003 33.9 0.086
2004 42.1 0.072
2005 55.9 0.051
2006 88.3 0.032
2007 144.4 0.033
2008 174.7 0.053
2009 187.4 0.076
2010 194.3 0.097
2011 198.9 0.115
2012 202.4 0.127
2013 205.4 0.133
2014 208.3 0.134
2015 211.3 0.128
2016 214.7 0.116
2017 219.2 0.098
2018 226.3 0.074
2019 241.2 0.047
2020 288.8 0.026
2021 352.4 0.038
2022 13.5 0.064
2023 23.0 0.083
2024 29.9 0.089
2025 36.9 0.081
2026 46.6 0.064
2027 65.4 0.043
2028 110.6 0.029
2029 160.1 0.040
2030 180.9 0.063


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


 
  


wds18084%2B4407a.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic