18084+4407 HDS2554

 
 
18H 08M 21.80S +44 06' 45.1" P.A. 226.3 SEP 0.07 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
205
P.A. Now (θ)
226.3°
Sep first
0.1
Sep last
0.1
Sep. Now (ρ)
0.07"
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
 
 
Constellation
Hercules
SAO
47250
HIP
88852
Tycho2
3114-01636-1
HD
166409
BD
BD+44 2829
Distance
101.21
Distance ly
330.15
last precise pa
204.7
last precise sep
0.135
 
 
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 Note Grade4(1=Definitive, 9=Indet.)
Equinox2000 Last observation2008
label rho theta
2000 0.054 7.5
2001 0.076 19.8
2002 0.088 27.2
2003 0.086 33.9
2004 0.072 42.1
2005 0.051 55.9
2006 0.032 88.3
2007 0.033 144.4
2008 0.053 174.7
2009 0.076 187.4
2010 0.097 194.3
2011 0.115 198.9
2012 0.127 202.4
2013 0.133 205.4
2014 0.134 208.3
2015 0.128 211.3
2016 0.116 214.7
2017 0.098 219.2
2018 0.074 226.3
2019 0.047 241.2
2020 0.026 288.8
2021 0.038 352.4
2022 0.064 13.5
2023 0.083 23.0
2024 0.089 29.9
2025 0.081 36.9
2026 0.064 46.6
2027 0.043 65.4
2028 0.029 110.6
2029 0.040 160.1
2030 0.063 180.9

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