20212-5147 HDS2907

Coord 2000	20212-5147		Discov num	HDS2907		Comp			Coord arcsec 2000	20 21 10.95 -51 47 28.6
Date first	1991		Date last	2019		Obs	10
Pa first	31		Pa last	14		P.A. Now (θ)	23°
Sep first	0.3		Sep last	0.2		Sep. Now (ρ)	0.26"
Mag pri	10.86		Mag sec	11.32		delta mag (ΔM)	0.46		Spectral class	M0 (red)
Pri motion ra	-040		Sec motion ra
Pri motion dec	+094		Sec motion dec
Notes	O (Orbital solution)

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

Precise pa	13.6		Precise sep	0.211		Constellation	Telescopium		HIP	100356
Tycho2	8417-00626-1		Gaia DR2	06723609600		GL	NN 4145		Distance	24.01
Distance ly	78.32		last precise pa	13.6		last precise sep	0.211

Period (P)	9.886y	± 0.129	Periastron (T)	2017.514y	± 0.016	Semi-major axis (a)	0.1948a	± 0.0047
Eccentricity (e)	0.651	± 0.016	Inclination (i)	48.8°	± 2.3	Longitude of periastron (ω)	194°	± 5.5
Node (Ω)	32.7°	± 3.2	Note			Grade	3	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation

label rho theta 2000 0.243 20.5 2001 0.294 30.0 2002 0.316 37.3 2003 0.313 44.2 2004 0.286 51.9 2005 0.235 62.0 2006 0.160 80.0 2007 0.079 137.8 2008 0.060 291.7 2009 0.168 5.9 2010 0.250 21.8 2011 0.298 30.9 2012 0.317 38.1 2013 0.311 45.0 2014 0.281 52.8 2015 0.228 63.5 2016 0.150 83.3 2017 0.074 151.3 2018 0.068 311.1 2019 0.179 8.5 2020 0.258 23.0 2021 0.301 31.8 2022 0.317 38.9 2023 0.309 45.9 2024 0.276 53.9 2025 0.220 65.0 2026 0.140 87.1 2027 0.072 166.0 2028 0.079 325.9 2029 0.190 10.8 2030 0.264 24.2 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
20212-5147	HDS2907		1991	1	31	0.3	10.86	11.32	M0		202110.95-514728.6
20212-5147	HDS2907		2014	2	60	0.2	10.86	11.32	M0		202110.95-514728.6
20212-5147	HDS2907		2015	3	72	0.2	10.86	11.32	M0		202110.95-514728.6
20212-5147	HDS2907		2017	7	210	0.1	10.86	11.32	M0		202110.95-514728.6
20212-5147	HDS2907		2018	9	359	0.1	10.86	11.32	M0	O	202110.95-514728.6
20212-5147	HDS2907		2019	10	14	0.2	10.86	11.32	M0	O	202110.95-514728.6

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