19520-1021 BU  148AB

Coord 2000	19520-1021		Discov num	BU  148		Comp	AB		Coord arcsec 2000	19 52 01.89 -10 21 13.5
Date first	1873		Date last	2017		Obs	71
Pa first	310		Pa last	223		P.A. Now (θ)	217°
Sep first	1.0		Sep last	0.6		Sep. Now (ρ)	0.56"
Mag pri	7.74		Mag sec	8.41		delta mag (ΔM)	0.67		Spectral class	F2 (yellow-white)
Pri motion ra	-014		Sec motion ra	-014
Pri motion dec	-049		Sec motion dec	-049
Notes	O (Orbital solution)

This double is physical.

Show	name	SAO	coord_2000	discov#	comp	first	last	obs	pa	sep	mag1	mag2	d_mag	orb	current
Show			19520-1021	BU 148	AB	1873	2017	71	217	0.6	7.74	8.41	0.67	Y	<===
Show			19520-1021	BU 148	AC	1891	2000	8	57	30.4	7.74	13.30	5.56

Triple system
3 visible stars in this system

Precise pa	222.6		Precise sep	0.619		Constellation	Aquila		HIP	97766
Tycho2	5729-01628-1		HD	187774		ADS	13028		Distance	86.96
Distance ly	283.66		last precise pa	222.6		last precise sep	0.619

Period (P)	783.31y		Periastron (T)	2032.84y		Semi-major axis (a)	1.365a
Eccentricity (e)	0.62		Inclination (i)	120.5°		Longitude of periastron (ω)	217.5°
Node (Ω)	38.1°		Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	2002

label rho theta 2000 0.613 234.5 2001 0.612 233.6 2002 0.611 232.7 2003 0.609 231.8 2004 0.607 230.9 2005 0.605 229.9 2006 0.603 229.0 2007 0.601 228.1 2008 0.598 227.1 2009 0.596 226.1 2010 0.593 225.2 2011 0.589 224.2 2012 0.586 223.2 2013 0.582 222.2 2014 0.577 221.2 2015 0.573 220.2 2016 0.568 219.1 2017 0.563 218.1 2018 0.558 217.0 2019 0.552 215.9 2020 0.546 214.7 2021 0.539 213.6 2022 0.533 212.4 2023 0.526 211.2 2024 0.518 209.9 2025 0.511 208.6 2026 0.503 207.3 2027 0.494 205.9 2028 0.486 204.5 2029 0.477 203.0 2030 0.468 201.5 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
19520-1021	BU 148	AB	2004	85	231	0.6	7.74	8.41	F2	NOD	195201.89-102113.5
19520-1021	BU 148	AB	2008	86	229	0.6	7.74	8.41	F2	NOD	195201.89-102113.5
19520-1021	BU 148	AB	2009	87	228	0.6	7.74	8.41	F2	NOD	195201.89-102113.5
19520-1021	BU 148	AB	2017	71	223	0.6	7.74	8.41	F2	O	195201.89-102113.5

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