02539-4436 I 1480 (HD 18198)

02^h 53^m 51.15^s -44° 36' 20.4" P.A. 115.00 sep 0.4 mag 7.95,9.76 Sp K0:III+ dist. 70.97 pc (231.5 l.y.)

Coord 2000	02539-4436		Discov num	I 1480		Comp			Coord arcsec 2000	02 53 51.15 -44 36 20.4
Date first	1927		Date last	2019		Obs	19
Pa first	126		Pa last	114.8		P.A. Now (θ)	119°
Sep first	0.4		Sep last	0.422		Sep. Now (ρ)	0.471"
Mag pri	7.95		Mag sec	9.76		delta mag (ΔM)	1.81		Spectral class	K0:III+ (yellow-orange)
Pri motion ra	+102		Sec motion ra	+102
Pri motion dec	+060		Sec motion dec	+060
Notes	O (Orbital solution)

This double is physical.

OTHER CATALOGS AND DESIGNATIONS

Name	HD 18198		Constellation	Eridanus		SAO	216086		HIP	13498
Tycho2	7566-00827-1		Gaia DR2	4755117967402573056		HD	18198		GC	3490
CD	CD-45 946		CP	CP-45 288		Distance	70.97		Distance ly	231.5

ORBITAL ELEMENTS

Period (P)	51.46y	± 0.82	Periastron (T)	2007.24y	± 0.14	Semi-major axis (a)	0.2967a	± 0.0044
Eccentricity (e)	0.774	± 0.013	Inclination (i)	49.5°	± 1.9	Longitude of periastron (ω)	16.2°	± 1.7
Node (Ω)	298.3°	± 1.3	Notes			Reference	Tok2016c
Equinox	2000		Last observation	2015		Grade	3	(1=Definitive, 9=Indet.)

label	theta	rho
2000	158.6	0.252
2001	163.1	0.223
2002	169.0	0.191
2003	177.3	0.159
2004	190.0	0.126
2005	211.3	0.095
2006	247.3	0.076
2007	295.6	0.069
2008	2.8	0.057
2009	58.0	0.088
2010	79.2	0.136
2011	89.4	0.181
2012	95.8	0.221
2013	100.2	0.258
2014	103.5	0.291
2015	106.3	0.320
2016	108.5	0.347
2017	110.5	0.370
2018	112.3	0.392
2019	113.8	0.411
2020	115.3	0.429
2021	116.6	0.445
2022	117.8	0.458
2023	119.0	0.471
2024	120.1	0.481
2025	121.2	0.490
2026	122.2	0.498
2027	123.2	0.504
2028	124.2	0.509
2029	125.2	0.513
2030	126.2	0.515

grafico orbita

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

wds02539-4436a.png orbit plot

Measures: green=micrometric, blue=interferometric, purple=photographic