18428+5938 STF 2398 AB (HD 173739)

 
 
18h 42m 46.69s +59° 37' 49.4" P.A. 181.00 sep 11.4 mag 9.11,9.96 Sp M3V+M3.5 dist. 3.57 pc (11.65 l.y.)
 
 
Coord 2000 18428+5938 Discov num STF2398 Comp AB Coord arcsec 2000 18 42 46.69 +59 37 49.4
Date first 1831 Date last 2020 Obs 641
Pa first 136 Pa last 180.8 P.A. Now (θ) 180.8°
Sep first 14.0 Sep last 11.4 Sep. Now (ρ) 11.4"
Mag pri 9.11 Mag sec 9.96 delta mag (ΔM) 0.85 Spectral class M3V+M3.5 (red/red)
Pri motion ra -133 Sec motion ra -139
Pri motion dec +180 Sec motion dec +185
Notes N O P (See Notes, Orbital solution, 100-year proper motion)
rPM=0.034 (< 0.3, Physical double)
This double is physical.
 
 
18428+5938 SYSTEM COMPONENTS
 
 
Show name SAO coord wds_name last obs pa sep mag1 mag2 d_mag orb current
Show HD 173739 31128 18 42 47 +59 37 49 STF 2398 AB 2020 641 181 11.4 9.11 9.96 0.85 Y <===
Show 31128 18 42 47 +59 37 49 STF 2398 AC 2013 21 158 216.8 9.11 12.24 3.13
Show 31128 18 42 47 +59 37 49 POP 1224 AD 2008 3 110 100.0 9.11 13.50 4.39
Show 31129 18 42 47 +59 37 37 STF 2398 BC 2000 18 157 202.7 9.96 12.24 2.28
Quadruple system
4 estimated visually detectable stars in this system
 
 
OTHER CATALOGS AND DESIGNATIONS
 
 
Name HD 173739 Constellation Draco SAO 31128 HIP 91768
Tycho2 3930-01791-1 HD 173739 GC 25648 ADS 11632
GL Gl 725A BD BD+59 1915 Distance 3.57 Distance ly 11.65
 
 
ORBITAL ELEMENTS
 
 
Period (P)408y Periastron (T)1775y Semi-major axis (a)13.88a
Eccentricity (e)0.53 Inclination (i)66° Longitude of periastron (ω)234.6°
Node (Ω)136.9° Notesn ReferenceHei1987b
Equinox2000 Last observation1987 Grade4(1=Definitive, 9=Indet.)
label theta rho
2000 173.6 12.596
2001 173.9 12.516
2002 174.3 12.436
2003 174.7 12.356
2004 175.1 12.275
2005 175.5 12.194
2006 175.9 12.113
2007 176.3 12.032
2008 176.7 11.950
2009 177.1 11.869
2010 177.5 11.787
2011 177.9 11.704
2012 178.4 11.622
2013 178.8 11.539
2014 179.2 11.457
2015 179.7 11.374
2016 180.2 11.291
2017 180.6 11.208
2018 181.1 11.125
2019 181.6 11.042
2020 182.0 10.959
2021 182.5 10.876
2022 183.0 10.793
2023 183.5 10.710
2024 184.1 10.627
2025 184.6 10.544
2026 185.1 10.462
2027 185.7 10.379
2028 186.2 10.297
2029 186.8 10.215
2030 187.3 10.132


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



 
 


wds18428%2B5938c.png orbit plot
Measures: green=micrometric, blue=interferometric, purple=photographic