20406+1539 HDS 2947 (HD 197039)

 
 
20h 40m 35.25s +15° 38' 35.3" P.A. 111.00 sep 0.2 mag 7.27,8.14 Sp F5 dist. 71.63 pc (233.66 l.y.)
 
 
Coord 2000 20406+1539 Discov num HDS2947 Comp Coord arcsec 2000 20 40 35.25 +15 38 35.3
Date first 1991 Date last 2021 Obs 38
Pa first 101 Pa last 110.6 P.A. Now (θ) 108.1°
Sep first 0.2 Sep last 0.196 Sep. Now (ρ) 0.222"
Mag pri 7.27 Mag sec 8.14 delta mag (ΔM) 0.87 Spectral class F5 (yellow-white)
Pri motion ra +094 Sec motion ra
Pri motion dec +045 Sec motion dec
Notes N O (See Notes, Orbital solution)
This double is physical.
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Name HD 197039 Constellation Delphinus SAO 106369 HIP 102029
Tycho2 1634-00576-1 Gaia DR2 1810621567612258048 HD 197039 GC 28807
BD BD+15 4227 Distance 71.63 Distance ly 233.66
 
 
ORBITAL ELEMENTS
 
 
Period (P)17.688y Periastron (T)2014.815y Semi-major axis (a)0.139a
Eccentricity (e)0.749 Inclination (i)104.3° Longitude of periastron (ω)158.3°
Node (Ω)101.6° Notes ReferenceTok2020g
Equinox2000 Last observation2019 Grade2(1=Definitive, 9=Indet.)
label theta rho
2000 122.1 0.093
2001 116.8 0.130
2002 113.8 0.160
2003 111.6 0.185
2004 109.9 0.204
2005 108.5 0.218
2006 107.2 0.227
2007 106.0 0.231
2008 104.7 0.229
2009 103.5 0.221
2010 102.1 0.207
2011 100.4 0.184
2012 98.1 0.152
2013 94.2 0.107
2014 80.2 0.040
2015 277.7 0.037
2016 176.3 0.023
2017 129.5 0.064
2018 120.1 0.105
2019 115.7 0.140
2020 113.0 0.168
2021 111.0 0.191
2022 109.4 0.209
2023 108.1 0.222
2024 106.8 0.229
2025 105.6 0.231
2026 104.4 0.227
2027 103.1 0.217
2028 101.6 0.201
2029 99.8 0.175
2030 97.2 0.140


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



 
 


wds20406%2B1539b.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic