20274+7245 A   871

Coord 2000	20274+7245		Discov num	A   871		Comp			Coord arcsec 2000	20 27 24.67 +72 44 38.2
Date first	1904		Date last	2008		Obs	15
Pa first	95		Pa last	184		P.A. Now (θ)	258.1°
Sep first	0.3		Sep last	0.3		Sep. Now (ρ)	0.13"
Mag pri	9.40		Mag sec	9.60		delta mag (ΔM)	0.2		Spectral class	F8 (yellow-white)
Pri motion ra	-003		Sec motion ra
Pri motion dec	-006		Sec motion dec
Notes	O (Orbital solution)

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

Precise pa	184		Precise sep	0.325		Constellation	Draco		SAO	9776
Tycho2	4455-00436-1		ADS	13914		last precise pa	184		last precise sep	0.325

Period (P)	149y		Periastron (T)	2024y		Semi-major axis (a)	0.316a
Eccentricity (e)	0.67		Inclination (i)	57°		Longitude of periastron (ω)	248°
Node (Ω)	72.1°		Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox			Last observation

label rho theta 2000 0.212 198.0 2001 0.210 200.2 2002 0.209 202.4 2003 0.207 204.7 2004 0.205 207.0 2005 0.203 209.3 2006 0.201 211.7 2007 0.199 214.1 2008 0.197 216.6 2009 0.195 219.2 2010 0.192 221.8 2011 0.189 224.5 2012 0.185 227.2 2013 0.181 230.1 2014 0.177 233.2 2015 0.171 236.4 2016 0.165 239.8 2017 0.158 243.6 2018 0.149 247.7 2019 0.138 252.5 2020 0.126 258.1 2021 0.112 264.9 2022 0.096 274.0 2023 0.080 286.7 2024 0.066 305.5 2025 0.058 331.7 2026 0.062 359.4 2027 0.075 20.4 2028 0.093 34.4 2029 0.112 43.8 2030 0.130 50.5 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
20274+7245	A 871		1997	13	196	0.3	9.40	9.60	F8	O	202724.67+724438.2
20274+7245	A 871		2007	14	183	0.3	9.40	9.60	F8	O	202724.67+724438.2
20274+7245	A 871		2008	15	184	0.3	9.40	9.60	F8	O	202724.67+724438.2

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