09278-0604 B 2530 (HD 81809)

09h 27m 46.78s -06° 04' 16.4" P.A. 143.00 sep 0.3 mag 5.63,7.52 Sp G2V dist. 30.41 pc (99.2 l.y.)

Coord 2000 09278-0604 Discov num B  2530 Comp Coord arcsec 2000 09 27 46.78 -06 04 16.4
Date first 1938 Date last 2021 Obs 77
Pa first 319 Pa last 143.2 P.A. Now (θ) 145.9°
Sep first 0.2 Sep last 0.259 Sep. Now (ρ) 0.357"
Mag pri 5.63 Mag sec 7.52 delta mag (ΔM) 1.89 Spectral class G2V (yellow)
Pri motion ra -227 Sec motion ra -227
Pri motion dec -077 Sec motion dec -077
Notes N O (See Notes, Orbital solution)




This double is physical.



OTHER CATALOGS AND DESIGNATIONS

Name HD 81809 Constellation Hydra SAO 136872 HIP 46404
Tycho2 4893-01379-1 Gaia DR2 5745464991235898752 HD 81809 HR 3750
GC 13048 GL Gl 344A BD BD-05 2802 Distance 30.41
Distance ly 99.2




ORBITAL ELEMENTS

Period (P)34.8y± 0.06 Periastron (T)2010.11y± 0.1 Semi-major axis (a)0.428a± 0.001
Eccentricity (e)0.27± 0.003 Inclination (i)85.4°± 0.1 Longitude of periastron (ω)341.9°± 1.1
Node (Ω)330.8°± 0.1 Notesn ReferenceTok2015c
Equinox2000 Last observation2014 Grade2(1=Definitive, 9=Indet.)

label theta rho
2000 153.5 0.415
2001 154.5 0.363
2002 155.8 0.302
2003 157.9 0.233
2004 161.9 0.156
2005 174.3 0.076
2006 271.2 0.034
2007 316.4 0.106
2008 323.9 0.183
2009 327.1 0.248
2010 329.1 0.293
2011 330.7 0.315
2012 332.1 0.312
2013 333.8 0.285
2014 335.9 0.240
2015 339.2 0.183
2016 346.0 0.117
2017 10.0 0.053
2018 103.1 0.048
2019 131.8 0.111
2020 139.2 0.178
2021 142.6 0.243
2022 144.6 0.303
2023 145.9 0.357
2024 146.9 0.405
2025 147.7 0.447
2026 148.4 0.480
2027 149.0 0.507
2028 149.6 0.525
2029 150.1 0.535
2030 150.6 0.536


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



 
 


wds09278-0604c.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic