19549+5049 HU 687 (HD 188871)
19h 54m 56.19s +50° 49' 11.9" P.A. 27.00 sep 0.2 mag 8.54,8.63 Sp A0 dist. 256.41 pc (836.41 l.y.)
Coord 2000 |
19549+5049 |
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Discov num |
HU 687 |
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Comp |
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Coord arcsec 2000 |
19 54 56.19 +50 49 11.9 |
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Date first |
1904 |
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Date last |
2008 |
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Obs |
45 |
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Pa first |
93 |
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Pa last |
26.9 |
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P.A. Now (θ) |
45° |
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Sep first |
0.2 |
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Sep last |
0.196 |
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Sep. Now (ρ) |
0.201" |
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Mag pri |
8.54 |
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Mag sec |
8.63 |
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delta mag (ΔM) |
0.09 |
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Spectral class |
A0 (white) |
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Pri motion ra |
+005 |
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Sec motion ra |
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Pri motion dec |
+025 |
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Sec motion dec |
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Notes |
N
O
(See Notes, Orbital solution) |
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This double is physical.
OTHER CATALOGS AND DESIGNATIONS
Name |
HD 188871 |
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Constellation |
Cygnus |
|
SAO |
32104 |
|
HIP |
97997 |
|
Tycho2 |
3570-00245-1 |
|
Gaia DR2 |
2088834258965337216 |
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HD |
188871 |
|
ADS |
13135 |
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BD |
BD+50 2920 |
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Distance |
256.41 |
|
Distance ly |
836.41 |
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ORBITAL ELEMENTS
Period (P) | 154.6y | |
Periastron (T) | 1960.63y | |
Semi-major axis (a) | 0.159a | |
Eccentricity (e) | 0.321 | |
Inclination (i) | 36.2° | |
Longitude of periastron (ω) | 218.9° | |
Node (Ω) | 28.9° | |
Notes | n | |
Reference | Doc2017f | |
Equinox | 2000 | |
Last observation | 2008 | |
Grade | 3 | (1=Definitive, 9=Indet.) |
label |
theta |
rho |
2000 |
16.5 |
0.174 |
2001 |
18.0 |
0.176 |
2002 |
19.4 |
0.178 |
2003 |
20.8 |
0.180 |
2004 |
22.2 |
0.182 |
2005 |
23.6 |
0.184 |
2006 |
24.9 |
0.185 |
2007 |
26.2 |
0.187 |
2008 |
27.5 |
0.188 |
2009 |
28.7 |
0.190 |
2010 |
30.0 |
0.191 |
2011 |
31.2 |
0.192 |
2012 |
32.4 |
0.194 |
2013 |
33.6 |
0.195 |
2014 |
34.8 |
0.196 |
2015 |
35.9 |
0.197 |
2016 |
37.1 |
0.197 |
2017 |
38.2 |
0.198 |
2018 |
39.4 |
0.199 |
2019 |
40.5 |
0.199 |
2020 |
41.6 |
0.200 |
2021 |
42.8 |
0.200 |
2022 |
43.9 |
0.200 |
2023 |
45.0 |
0.201 |
2024 |
46.1 |
0.201 |
2025 |
47.3 |
0.201 |
2026 |
48.4 |
0.201 |
2027 |
49.5 |
0.201 |
2028 |
50.6 |
0.200 |
2029 |
51.7 |
0.200 |
2030 |
52.8 |
0.200 |
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Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.
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Measures: green=micrometric, blue=interferometric, purple=photographic |
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