21186+1134 BU 163 AB (HD 202908)
21h 18m 34.85s +11° 34' 08.2" P.A. 257.00 sep 1.0 mag 7.31,8.88 Sp G2.7V+G5V dist. 47.66 pc (155.47 l.y.)
| Coord 2000 |
21186+1134 |
|
Discov num |
BU 163 |
|
Comp |
AB |
|
Coord arcsec 2000 |
21 18 34.85 +11 34 08.2 |
|
| Date first |
1873 |
|
Date last |
2021 |
|
Obs |
229 |
|
| Pa first |
260 |
|
Pa last |
257.3 |
|
P.A. Now (θ) |
256.9° |
|
| Sep first |
1.0 |
|
Sep last |
0.954 |
|
Sep. Now (ρ) |
0.946" |
|
| Mag pri |
7.31 |
|
Mag sec |
8.88 |
|
delta mag (ΔM) |
1.57 |
|
Spectral class |
G2.7V+G5V (yellow/yellow) |
|
| Pri motion ra |
+032 |
|
Sec motion ra |
|
|
| Pri motion dec |
-056 |
|
Sec motion dec |
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|
| Notes |
N
O
(See Notes, Orbital solution) |
|
This double is physical.
21186+1134 SYSTEM COMPONENTS
| Show |
name |
SAO |
coord |
wds_name |
last |
obs |
pa |
sep |
mag1 |
mag2 |
d_mag |
orb |
current |
| Show |
HD 202908 |
107015 |
21 18 35 +11 34 08 |
BU 163 AB |
2021 |
229 |
257 |
1.0 |
7.31 |
8.88 |
1.57 |
Y |
<=== |
| Show |
|
107015 |
21 18 35 +11 34 08 |
BU 163 AC |
2015 |
6 |
252 |
29.7 |
7.31 |
15.00 |
7.69 |
|
|
| Show |
|
107015 |
21 18 35 +11 34 08 |
BU 163 AD |
2015 |
6 |
163 |
44.8 |
7.31 |
14.40 |
7.09 |
|
|
| Show |
|
107015 |
21 18 35 +11 34 08 |
BU 163 AE |
2015 |
12 |
6 |
87.5 |
7.31 |
12.67 |
5.36 |
|
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Quintuple system
5 estimated visually detectable stars in this system
OTHER CATALOGS AND DESIGNATIONS
| Name |
HD 202908 |
|
Constellation |
Equuleus |
|
SAO |
107015 |
|
HIP |
105200 |
|
| Tycho2 |
1113-00330-1 |
|
Gaia DR2 |
1746335802793081344 |
|
HD |
202908 |
|
GC |
29812 |
|
| ADS |
14839 |
|
BD |
BD+10 4514 |
|
Distance |
47.66 |
|
Distance ly |
155.47 |
|
ORBITAL ELEMENTS
| Period (P) | 78.54y | |
Periastron (T) | 1987.048y | |
Semi-major axis (a) | 0.5177a | |
| Eccentricity (e) | 0.8651 | |
Inclination (i) | 100.36° | |
Longitude of periastron (ω) | 171.92° | |
| Node (Ω) | 255.03° | |
Notes | n | |
Reference | Fek1997 | |
| Equinox | | |
Last observation | | |
Grade | 2 | (1=Definitive, 9=Indet.) |
| label |
theta |
rho |
| 2000 |
261.1 |
0.560 |
| 2001 |
260.8 |
0.591 |
| 2002 |
260.5 |
0.620 |
| 2003 |
260.2 |
0.648 |
| 2004 |
259.9 |
0.674 |
| 2005 |
259.7 |
0.699 |
| 2006 |
259.5 |
0.722 |
| 2007 |
259.3 |
0.744 |
| 2008 |
259.1 |
0.765 |
| 2009 |
258.9 |
0.785 |
| 2010 |
258.7 |
0.803 |
| 2011 |
258.6 |
0.820 |
| 2012 |
258.4 |
0.836 |
| 2013 |
258.2 |
0.851 |
| 2014 |
258.1 |
0.865 |
| 2015 |
258.0 |
0.878 |
| 2016 |
257.8 |
0.890 |
| 2017 |
257.7 |
0.901 |
| 2018 |
257.5 |
0.911 |
| 2019 |
257.4 |
0.920 |
| 2020 |
257.3 |
0.928 |
| 2021 |
257.1 |
0.935 |
| 2022 |
257.0 |
0.941 |
| 2023 |
256.9 |
0.946 |
| 2024 |
256.8 |
0.950 |
| 2025 |
256.7 |
0.953 |
| 2026 |
256.5 |
0.956 |
| 2027 |
256.4 |
0.957 |
| 2028 |
256.3 |
0.958 |
| 2029 |
256.2 |
0.957 |
| 2030 |
256.0 |
0.955 |
|
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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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