18500+1519 YSC 12 AB (HD 174457)

Coord 2000	18500+1519		Discov num	YSC  12		Comp	AB		Coord arcsec 2000	18 50 02.00 +15 18 40.3
Date first	2001		Date last	2019		Obs	19
Pa first	77		Pa last	35		P.A. Now (θ)	35°
Sep first	0.4		Sep last	0.479		Sep. Now (ρ)	0.479"
Mag pri	7.60		Mag sec	11.30		delta mag (ΔM)	3.7		Spectral class	F8+M2V (yellow-white/red)
Pri motion ra	+102		Sec motion ra
Pri motion dec	+131		Sec motion dec
Notes	N O (See Notes, Orbital solution)

This double is physical.

Show	name	SAO	coord	wds_name	last	obs	pa	sep	mag1	mag2	d_mag	orb	current
Show	HD 174457	104160	18 50 02 +15 18 40	YSC 12 AB	2019	19	35	0.5	7.60	11.30	3.70	Y	<===
Show		104160	18 50 02 +15 18 40	LLO 16 AC	2001	2	19	11.1	5.99	13.30	7.31
Show		104160	18 50 02 +15 18 40	LLO 16 AD	2015	4	225	15.7	5.99	13.50	7.51

Quadruple system
4 estimated visually detectable stars in this system

Name	HD 174457		Constellation	Hercules		SAO	104160		HIP	92418
Tycho2	1584-00540-1		Gaia DR2	4507523307652284288		HD	174457		GC	25831
BD	BD+15 3584		Distance	53.22		Distance ly	173.6

Period (P)	105y		Periastron (T)	2121.131y		Semi-major axis (a)	0.486a
Eccentricity (e)	0		Inclination (i)	143.4°		Longitude of periastron (ω)	0°
Node (Ω)	45.4°		Notes			Reference	Tok2018e
Equinox	2000		Last observation	2018		Grade	5	(1=Definitive, 9=Indet.)

label theta rho 2000 94.6 0.424 2001 91.1 0.429 2002 87.6 0.435 2003 84.2 0.441 2004 80.9 0.446 2005 77.6 0.452 2006 74.5 0.457 2007 71.4 0.462 2008 68.4 0.467 2009 65.5 0.471 2010 62.5 0.475 2011 59.7 0.478 2012 56.9 0.481 2013 54.1 0.483 2014 51.3 0.485 2015 48.5 0.486 2016 45.8 0.486 2017 43.0 0.486 2018 40.2 0.485 2019 37.5 0.483 2020 34.7 0.481 2021 31.9 0.479 2022 29.0 0.476 2023 26.1 0.472 2024 23.2 0.468 2025 20.2 0.463 2026 17.1 0.458 2027 14.0 0.453 2028 10.8 0.448 2029 7.5 0.442 2030 4.1 0.436		Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.
		Measures: green=micrometric, blue=interferometric, purple=photographic