20057-3743 HDS2865

Coord 2000	20057-3743		Discov num	HDS2865		Comp			Coord arcsec 2000	20 05 41.20 -37 42 53.2
Date first	1991		Date last	2019		Obs	8
Pa first	51		Pa last	206		P.A. Now (θ)	194.1°
Sep first	0.2		Sep last	0.1		Sep. Now (ρ)	0.12"
Mag pri	8.53		Mag sec	9.11		delta mag (ΔM)	0.58		Spectral class	F3V (yellow-white)
Pri motion ra	+017		Sec motion ra
Pri motion dec	-007		Sec motion dec
Notes	O (Orbital solution)

Visually invisible, K-band or other infrared star This double is physical.

Precise pa	205.6		Precise sep	0.109		Constellation	Sagittarius		SAO	211799
HIP	98979		Tycho2	7947-03226-1		Gaia DR2	83945134080		HD	190289
CD	CD-3813850		CP	CP-38 7940		Distance	149.03		Distance ly	486.14
last precise pa	205.6		last precise sep	0.109

Period (P)	50y		Periastron (T)	2018.71y	± 0.56	Semi-major axis (a)	0.1778a	± 0.0043
Eccentricity (e)	0.328	± 0.04	Inclination (i)	131.5°	± 4.2	Longitude of periastron (ω)	131.7°	± 6.6
Node (Ω)	4.2°	± 3.7	Note			Grade	4	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation

label rho theta 2000 0.216 20.1 2001 0.216 17.1 2002 0.214 14.0 2003 0.212 10.9 2004 0.208 7.6 2005 0.203 4.3 2006 0.197 0.7 2007 0.189 356.9 2008 0.179 352.6 2009 0.168 347.9 2010 0.156 342.5 2011 0.142 336.1 2012 0.128 328.3 2013 0.113 318.4 2014 0.100 305.8 2015 0.089 289.7 2016 0.084 270.5 2017 0.085 250.3 2018 0.092 232.0 2019 0.102 216.8 2020 0.113 204.4 2021 0.122 194.1 2022 0.130 185.2 2023 0.134 177.0 2024 0.137 169.3 2025 0.138 161.8 2026 0.138 154.3 2027 0.137 146.7 2028 0.135 139.0 2029 0.134 131.1 2030 0.133 123.2 Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.
		Measures: green=micrometric, blue=interferometric, purple=photographic

coord_2000	discov_num	comp	epoch	obs	pa	sep	mag_pri	mag_sec	spectr	notes	coord_arcsec_2000
20057-3743	HDS2865		1991	1	51	0.2	8.53	9.11	F3V		200541.20-374253.2
20057-3743	HDS2865		2008	2	170	0.2	8.53	9.11	F3V		200541.20-374253.2
20057-3743	HDS2865		2014	3	293	0.1	8.53	9.11	F3V		200541.20-374253.2
20057-3743	HDS2865		2015	5	276	0.1	8.53	9.11	F3V		200541.20-374253.2
20057-3743	HDS2865		2017	6	239	0.1	8.53	9.11	F3V	O	200541.20-374253.2
20057-3743	HDS2865		2018	7	224	0.1	8.53	9.11	F3V	O	200541.20-374253.2
20057-3743	HDS2865		2019	8	206	0.1	8.53	9.11	F3V	O	200541.20-374253.2

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