20012-3835 HDO 294

Coord 2000	20012-3835		Discov num	HDO 294		Comp			Coord arcsec 2000	20 01 12.74 -38 35 12.7
Date first	1897		Date last	2017		Obs	61
Pa first	120		Pa last	34		P.A. Now (θ)	36.5°
Sep first	1.5		Sep last	1.3		Sep. Now (ρ)	1.39"
Mag pri	8.08		Mag sec	9.11		delta mag (ΔM)	1.03		Spectral class	F3V (yellow-white)
Pri motion ra	+018		Sec motion ra	+018
Pri motion dec	-070		Sec motion dec	-070
Notes	N O (See Notes, Orbital solution)

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

Precise pa	33.9		Precise sep	1.254		Constellation	Sagittarius		SAO	211734
HIP	98556		Tycho2	7947-00530-1		Gaia DR2	08575405056		HD	189386
CD	CD-3813809		CP	CP-38 7919		Distance	68.49		Distance ly	223.41
last precise pa	33.9		last precise sep	1.254

Period (P)	4484.5y		Periastron (T)	1922.73y		Semi-major axis (a)	4.916a
Eccentricity (e)	0.9474		Inclination (i)	40.86°		Longitude of periastron (ω)	137.62°
Node (Ω)	116.65°		Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox	1900		Last observation	1974

label rho theta 2000 1.173 30.7 2001 1.184 31.0 2002 1.195 31.4 2003 1.206 31.7 2004 1.217 32.0 2005 1.228 32.3 2006 1.239 32.6 2007 1.250 32.9 2008 1.261 33.2 2009 1.271 33.5 2010 1.282 33.8 2011 1.293 34.1 2012 1.304 34.4 2013 1.314 34.7 2014 1.325 34.9 2015 1.336 35.2 2016 1.346 35.5 2017 1.357 35.7 2018 1.367 36.0 2019 1.378 36.2 2020 1.388 36.5 2021 1.399 36.7 2022 1.409 36.9 2023 1.419 37.2 2024 1.430 37.4 2025 1.440 37.6 2026 1.450 37.9 2027 1.460 38.1 2028 1.471 38.3 2029 1.481 38.5 2030 1.491 38.7 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
20012-3835	HDO 294		2002	52	30	1.2	8.08	9.11	F3V	NOD	200112.74-383512.7
20012-3835	HDO 294		2008	53	30	1.2	8.08	9.11	F3V	NOD	200112.74-383512.7
20012-3835	HDO 294		2010	54	29	1.2	8.08	9.11	F3V	NOD	200112.74-383512.7
20012-3835	HDO 294		2013	57	31	1.2	8.08	9.11	F3V	NO	200112.74-383512.7
20012-3835	HDO 294		2016	60	35	1.3	8.08	9.11	F3V	NO	200112.74-383512.7
20012-3835	HDO 294		2017	61	34	1.3	8.08	9.11	F3V	NO	200112.74-383512.7

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