02318+8916 WRH 39 Aa,Ab

 
 
02h 31m 49.09s +89 15' 50.7" P.A. 175.00 sep 0.1 mag 2.30,4.30 Sp F7:Ib-IIv dist. 132.63 pc (432.64 l.y.)
 
 
Coord 2000 02318+8916 Discov num WRH  39 Comp Aa,Ab Coord arcsec 2000 02 31 49.09 +89 15 50.7
Date first 1937 Date last 2014 Obs 8
Pa first 250 Pa last 175 P.A. Now (θ) 175°
Sep first 0.2 Sep last 0.085 Sep. Now (ρ) 0.085"
Mag pri 2.30 Mag sec 4.30 delta mag (ΔM) 2 Spectral class F7:Ib-IIv (yellow-white)
Pri motion ra +038 Sec motion ra
Pri motion dec -015 Sec motion dec
Notes N O (See Notes, Orbital solution)
This double is physical.
 
 
02318+8916 SYSTEM COMPONENTS
 
 
Show name SAO coord wds_name last obs pa sep mag1 mag2 d_mag orb current
Show 308 02 31 49 +89 15 51 WRH 39 Aa,Ab 2014 8 175 0.1 2.30 4.30 2.00 Y <===
Show Polaris 308 02 31 49 +89 15 51 STF 93 AB 2016 65 236 18.4 2.04 9.10 7.06
Show 308 02 31 49 +89 15 51 STF 93 AC 2016 7 103 39.0 2.04 13.80 11.76
Show 308 02 31 49 +89 15 51 STF 93 AD 2016 8 194 83.2 2.04 14.30 12.26
Show 02 30 43 +89 15 39 STF 93 BC 2015 4 83 53.1 9.10 13.80 4.70
Show 02 30 43 +89 15 39 STF 93 BD 2014 3 179 69.4 9.10 14.30 5.20
Quintuple system
4 estimated visually detectable stars in this system
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Common name Polaris Constellation Ursa Minor SAO 308 HIP 11767
Tycho2 4628-00237-1 Gaia DR2 576402619921505664 HD 8890 HR 424
GC 2243 ADS 1477 BD BD+88 8 Bayer Alpha Ursae Minoris
Bayer name Alp UMi Flamsteed 1 Ursae Minoris Flamsteed name 1 UMi FK5 907
Distance 132.63 Distance ly 432.64 Bayer greek α UMi
Other names Lodestar, Cynosura, Alruccabah, Phoenice, Polare, Stella Polare, Tramontana, Angel Stern, Navigatoria, Star of Arcady, Yilduz, Mismar, Polyarnaya
 
 
ORBITAL ELEMENTS
 
 
Period (P)29.59y± 0.02 Periastron (T)1987.66y± 0.13 Semi-major axis (a)0.1204a± 0.0059
Eccentricity (e)0.608± 0.005 Inclination (i)146.2°± 10.9 Longitude of periastron (ω)303.01°± 0.75
Node (Ω)191.4°± 4.9 Notesn ReferenceEvs2018
Equinox2000 Last observation2014 Grade4(1=Definitive, 9=Indet.)
label theta rho
2000 73.5 0.163
2001 69.3 0.167
2002 65.2 0.170
2003 61.2 0.172
2004 57.3 0.173
2005 53.4 0.173
2006 49.5 0.171
2007 45.5 0.169
2008 41.3 0.165
2009 36.9 0.159
2010 32.1 0.151
2011 26.7 0.142
2012 20.4 0.130
2013 12.7 0.116
2014 2.6 0.098
2015 347.3 0.077
2016 319.1 0.054
2017 260.7 0.041
2018 202.5 0.052
2019 170.0 0.068
2020 149.2 0.082
2021 134.0 0.094
2022 122.2 0.105
2023 112.6 0.115
2024 104.5 0.125
2025 97.5 0.134
2026 91.4 0.142
2027 85.9 0.149
2028 80.8 0.155
2029 76.2 0.161
2030 71.8 0.165


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



 
 


wds02318%2B8916d.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic