17104-1544 BU 1118AB (Eta Oph)

 
 
17H 10M 22.66S -15 43' 30.5" P.A. 230.2 SEP 0.55 MAG 3.05,3.27 SP A1IV+A1IV DIST. 27.09 PC (88.37 L.Y.)
 
 
Coord 2000
17104-1544
Discov num
BU 1118
Comp
AB
Coord arcsec 2000
17 10 22.66 -15 43 30.5
Date first
1889
Date last
2016
Obs
225
Pa first
274
Pa last
231
P.A. Now (θ)
230.2°
Sep first
0.4
Sep last
0.6
Sep. Now (ρ)
0.55"
Mag pri
3.05
Mag sec
3.27
delta mag (ΔM)
0.22
Spectral class
A1IV+A1IV (white/white)
Pri motion ra
+045
Sec motion ra
Pri motion dec
+064
Sec motion dec
Notes
N O (See Notes, Orbital solution)
This double is physical.
 
 
17104-1544 SYSTEM COMPONENTS
 
 
Show name SAO coord_2000 discov# comp first last obs pa sep mag1 mag2 d_mag orb current
Show Eta Oph 160332 17104-1544 BU 1118 AB 1889 2016 225 230 0.6 3.05 3.27 0.22 Y <===
Show 160332 17104-1544 BU 1118 AB,C 1890 2012 6 148 99.8 2.42 12.34 9.92
Show 160332 17104-1544 BU 1118 AD 1898 2012 8 281 101.2 2.42 11.20 8.78
Show 160332 17104-1544 DAL 52 AE 1998 2012 2 317 62.7 2.42 11.10 8.68
Quintuple system
6 visible stars in this system
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Name
Eta Oph
Constellation
Ophiuchus
SAO
160332
HIP
84012
Tycho2
6232-01333-1
HD
155125
HR
6378
GC
23158
ADS
10374
GL
Gl 656.1A
BD
BD-15 4467
Bayer
Eta Ophiuchi
Bayer name
Eta Oph
Flamsteed
35 Ophiuchi
Flamsteed name
35 Oph
Distance
27.09
Distance ly
88.37
last precise pa
231.1
last precise sep
0.554
 
 
ORBITAL ELEMENTS
 
 
Period (P)87.58y± 1 Periastron (T)2024.68y± 0.5 Semi-major axis (a)1.396a± 0.01
Eccentricity (e)0.95± 0.02 Inclination (i)95.2°± 2 Longitude of periastron (ω)274.8°± 2
Node (Ω)38.9°± 1 Note Grade2(1=Definitive, 9=Indet.)
Equinox2000 Last observation2006
label rho theta
2000 0.532 242.3
2001 0.540 241.5
2002 0.547 240.7
2003 0.554 240.0
2004 0.560 239.2
2005 0.566 238.5
2006 0.571 237.8
2007 0.575 237.1
2008 0.578 236.4
2009 0.580 235.8
2010 0.581 235.1
2011 0.581 234.4
2012 0.580 233.8
2013 0.577 233.1
2014 0.573 232.4
2015 0.567 231.7
2016 0.558 231.0
2017 0.546 230.2
2018 0.532 229.5
2019 0.512 228.6
2020 0.487 227.7
2021 0.455 226.7
2022 0.410 225.5
2023 0.345 223.9
2024 0.228 221.2
2025 0.143 38.1
2026 0.266 33.0
2027 0.310 30.3
2028 0.332 28.1
2029 0.344 26.1
2030 0.350 24.2

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

grafico orbita





grafico misure orbit6
Measures: green=micrometric, blue=interferometric, purple=photographic