12155-3106 RST1658

 
 
12H 15M 26.96S -31 05' 38.2" P.A. 171.8 SEP 0.54 MAG 10.17,11.32 SP K7V DIST. 21.4 PC (69.81 L.Y.)
 
 
Coord 2000
12155-3106
Discov num
RST1658
Comp
Coord arcsec 2000
12 15 26.96 -31 05 38.2
Date first
1931
Date last
2014
Obs
24
Pa first
82
Pa last
154
P.A. Now (θ)
171.8°
Sep first
0.4
Sep last
0.6
Sep. Now (ρ)
0.54"
Mag pri
10.17
Mag sec
11.32
delta mag (ΔM)
1.15
Spectral class
K7V (yellow-orange)
Pri motion ra
+164
Sec motion ra
Pri motion dec
-074
Sec motion dec
Notes
O (Orbital solution)
This double is physical.
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Constellation
Hydra
SAO
203284
HIP
59780
Tycho2
7232-00584-1
HD
106549
CD
CD-30 9789
CP
CP-30 3447
Distance
21.4
Distance ly
69.81
last precise pa
153.6
last precise sep
0.649
 
 
ORBITAL ELEMENTS
 
 
Period (P)61.2y Periastron (T)1984.8y Semi-major axis (a)0.671a
Eccentricity (e)0.22 Inclination (i)53° Longitude of periastron (ω)244°
Node (Ω)112.7° Note Grade4(1=Definitive, 9=Indet.)
Equinox2000 Last observation1991
label rho theta
2000 0.701 111.4
2001 0.714 114.6
2002 0.724 117.6
2003 0.729 120.5
2004 0.730 123.4
2005 0.728 126.3
2006 0.723 129.3
2007 0.715 132.3
2008 0.703 135.4
2009 0.690 138.6
2010 0.674 141.9
2011 0.657 145.4
2012 0.638 149.1
2013 0.618 153.1
2014 0.598 157.3
2015 0.578 161.8
2016 0.558 166.6
2017 0.539 171.8
2018 0.522 177.3
2019 0.507 183.2
2020 0.494 189.4
2021 0.485 195.9
2022 0.479 202.6
2023 0.477 209.4
2024 0.478 216.2
2025 0.483 223.0
2026 0.491 229.5
2027 0.502 235.8
2028 0.515 241.9
2029 0.529 247.6
2030 0.543 253.0

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