20210+1028 J   838

Coord 2000	20210+1028		Discov num	J   838		Comp			Coord arcsec 2000	20 21 00.67 +10 28 21.0
Date first	1912		Date last	2018		Obs	35
Pa first	231		Pa last	119		P.A. Now (θ)	120.1°
Sep first	2.9		Sep last	6.9		Sep. Now (ρ)	6.18"
Mag pri	12.50		Mag sec	12.60		delta mag (ΔM)	0.1		Spectral class
Pri motion ra	-018		Sec motion ra	+040
Pri motion dec	-007		Sec motion dec	-026
Notes	N O (See Notes, Orbital solution)

Visually invisible, K-band or other infrared star rPM=1.279 This double is physical.

Precise pa	118.5		Precise sep	6.882		Constellation	Delphinus		Gaia DR2	20839173888
HD	357347		ADS	13734		last precise pa	118.5		last precise sep	6.882

Period (P)	239.84y		Periastron (T)	1967.51y		Semi-major axis (a)	7.451a
Eccentricity (e)	0.784		Inclination (i)	77.6°		Longitude of periastron (ω)	258.1°
Node (Ω)	103°		Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	1995

label rho theta 2000 5.925 113.9 2001 5.961 114.2 2002 5.995 114.5 2003 6.025 114.8 2004 6.052 115.1 2005 6.077 115.4 2006 6.099 115.7 2007 6.118 116.0 2008 6.135 116.3 2009 6.150 116.6 2010 6.163 116.9 2011 6.173 117.2 2012 6.181 117.5 2013 6.188 117.8 2014 6.192 118.1 2015 6.195 118.4 2016 6.195 118.7 2017 6.195 119.0 2018 6.192 119.3 2019 6.188 119.5 2020 6.182 119.8 2021 6.175 120.1 2022 6.167 120.4 2023 6.157 120.7 2024 6.145 121.0 2025 6.133 121.3 2026 6.119 121.6 2027 6.104 121.9 2028 6.088 122.2 2029 6.070 122.5 2030 6.052 122.8 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
20210+1028	J 838		2005	17	118	6.3	11.52	12.00		OD	202100.67+102821.0
20210+1028	J 838		2009	19	117	6.3	11.52	12.00		OD	202100.67+102821.0
20210+1028	J 838		2010	20	118	6.4	11.52	12.00		OD	202100.67+102821.0
20210+1028	J 838		2011	22	118	6.5	11.52	12.00		NOD	202100.67+102821.0
20210+1028	J 838		2013	23	118	6.6	12.50	12.60		NO	202100.67+102821.0
20210+1028	J 838		2015	24	119	6.7	12.50	12.60		NO	202100.67+102821.0
20210+1028	J 838		2016	27	119	6.8	12.50	12.60		NO	202100.67+102821.0
20210+1028	J 838		2018	32	119	6.9	12.50	12.60		NO	202100.67+102821.0

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