20311+1548 A  1675

 
 
20h 31m 06.12s +15 48' 27.5" P.A. 299.3 sep 0.15 mag 7.14,8.65 Sp A2V dist. 168.92 pc (551.02 l.y.)
 
 
Coord 2000
20311+1548
Discov num
A  1675
Comp
Coord arcsec 2000
20 31 06.12 +15 48 27.5
Date first
1907
Date last
2018
Obs
84
Pa first
327
Pa last
301
P.A. Now (θ)
299.3°
Sep first
0.2
Sep last
0.1
Sep. Now (ρ)
0.15"
Mag pri
7.14
Mag sec
8.65
delta mag (ΔM)
1.51
Spectral class
A2V (white)
Pri motion ra
-003
Sec motion ra
Pri motion dec
-009
Sec motion dec
Notes
N O (See Notes, Orbital solution)
This double is physical.
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Precise pa
301.3
Precise sep
0.139
Constellation
Delphinus
SAO
106194
HIP
101223
Tycho2
1632-01088-1
Gaia DR2
37932800896
HD
195481
ADS
13944
BD
BD+15 4181
Distance
168.92
Distance ly
551.02
last precise pa
301.3
last precise sep
0.139
 
 
ORBITAL ELEMENTS
 
 
Period (P)49.62y Periastron (T)1947.75y Semi-major axis (a)0.145a
Eccentricity (e)0.568 Inclination (i)109.4° Longitude of periastron (ω)60.2°
Node (Ω)142.6° Note Grade2(1=Definitive, 9=Indet.)
Equinox2000 Last observation1994
label rho theta
2000 0.056 344.4
2001 0.080 335.2
2002 0.100 330.1
2003 0.117 326.5
2004 0.131 323.8
2005 0.142 321.6
2006 0.151 319.6
2007 0.158 317.9
2008 0.163 316.3
2009 0.166 314.7
2010 0.169 313.2
2011 0.170 311.8
2012 0.170 310.4
2013 0.170 308.9
2014 0.168 307.4
2015 0.165 305.9
2016 0.162 304.4
2017 0.159 302.8
2018 0.154 301.1
2019 0.149 299.3
2020 0.144 297.3
2021 0.138 295.2
2022 0.132 292.9
2023 0.125 290.4
2024 0.118 287.6
2025 0.112 284.4
2026 0.104 280.9
2027 0.097 276.8
2028 0.091 272.0
2029 0.084 266.5
2030 0.078 260.1

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






wds20311%2B1548a.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic
 
 
 
WDS HISTORIC DATA
 
 
coord_2000 discov_num comp epoch obs pa sep mag_pri mag_sec spectr notes coord_arcsec_2000
20311+1548 A 1675 1994 80 148 0.1 7.14 8.65 A2V NOD 203106.12+154827.5
20311+1548 A 1675 2006 81 323 0.1 7.14 8.65 A2V NOD 203106.12+154827.5
20311+1548 A 1675 2015 83 306 0.2 7.14 8.65 A2V NO 203106.12+154827.5

If you need more information about this double, apply for a data request form to the WDS.