18003+2154 A 1374 AB

18^h 00^m 17.93^s +21° 53' 47.5" P.A. 210.00 sep 0.5 mag 8.90,10.90 Sp G0

Coord 2000	18003+2154		Discov num	A 1374		Comp	AB		Coord arcsec 2000	18 00 17.93 +21 53 47.5
Date first	1906		Date last	2021		Obs	38
Pa first	10		Pa last	210.1		P.A. Now (θ)	210.1°
Sep first	0.7		Sep last	0.522		Sep. Now (ρ)	0.522"
Mag pri	8.90		Mag sec	10.90		delta mag (ΔM)	2		Spectral class	G0 (yellow)
Pri motion ra	-030		Sec motion ra
Pri motion dec	+014		Sec motion dec
Notes	N O (See Notes, Orbital solution)

This double is physical.

18003+2154 SYSTEM COMPONENTS

Show	name	SAO	coord	wds_name	last	obs	pa	sep	mag1	mag2	d_mag	orb	current
Show		85624	18 00 18 +21 53 48	WSI 106 Aa,Ab	2021	6	267	0.0	9.40	9.90	0.50
Show		85624	18 00 18 +21 53 48	A 1374 AB	2021	38	210	0.5	8.90	10.90	2.00	Y	<===
Show	HD 341480	85624	18 00 18 +21 53 48	LBU 6 AB,C	2015	10	298	76.4	8.61	11.33	2.72

Quintuple system
4 estimated visually detectable stars in this system

OTHER CATALOGS AND DESIGNATIONS

Constellation	Hercules		SAO	85624		Tycho2	1566-01708-1		Gaia DR2	4576215537102834048
HD	341480		ADS	10971

ORBITAL ELEMENTS SOLUTION #1

Period (P)	139.53y		Periastron (T)	1995.81y		Semi-major axis (a)	0.504a
Eccentricity (e)	0.806		Inclination (i)	136.7°		Longitude of periastron (ω)	76°
Node (Ω)	249°		Notes	n		Reference	Msn2017a
Equinox	2000		Last observation	2015		Grade	4	(1=Definitive, 9=Indet.)

label	theta	rho
2000	73.4	0.198
2001	67.2	0.229
2002	62.4	0.256
2003	58.5	0.282
2004	55.2	0.305
2005	52.4	0.326
2006	49.9	0.346
2007	47.6	0.365
2008	45.6	0.382
2009	43.8	0.398
2010	42.0	0.414
2011	40.5	0.429
2012	39.0	0.443
2013	37.6	0.456
2014	36.2	0.468
2015	35.0	0.480
2016	33.8	0.492
2017	32.7	0.502
2018	31.6	0.513
2019	30.5	0.523
2020	29.5	0.532
2021	28.5	0.541
2022	27.6	0.550
2023	26.6	0.558
2024	25.7	0.566
2025	24.9	0.574
2026	24.0	0.581
2027	23.2	0.588
2028	22.4	0.594
2029	21.6	0.601
2030	20.8	0.607

grafico orbita

Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.

wds18003%2B2154a.png orbit plot

Measures: green=micrometric, blue=interferometric, purple=photographic

ORBITAL ELEMENTS SOLUTION #2

Period (P)	497y	± 222	Periastron (T)	1978.1y	± 3.1	Semi-major axis (a)	0.98a	± 0.24
Eccentricity (e)	0.41	± 0.18	Inclination (i)	124.1°	± 2	Longitude of periastron (ω)	233°	± 9
Node (Ω)	166°	± 5.2	Notes	n		Reference	Mdz2017
Equinox	2000		Last observation			Grade	5	(1=Definitive, 9=Indet.)

label	theta	rho
2000	251.3	0.348
2001	248.4	0.352
2002	245.5	0.356
2003	242.7	0.360
2004	240.0	0.365
2005	237.4	0.371
2006	234.9	0.378
2007	232.4	0.385
2008	230.1	0.392
2009	227.8	0.400
2010	225.6	0.408
2011	223.5	0.416
2012	221.5	0.425
2013	219.6	0.434
2014	217.7	0.444
2015	216.0	0.453
2016	214.3	0.463
2017	212.7	0.473
2018	211.1	0.483
2019	209.6	0.494
2020	208.2	0.504
2021	206.8	0.514
2022	205.5	0.525
2023	204.2	0.536
2024	203.0	0.546
2025	201.8	0.557
2026	200.7	0.568
2027	199.6	0.578
2028	198.6	0.589
2029	197.6	0.600
2030	196.6	0.610

grafico orbita

Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.

wds18003%2B2154e.png orbit plot

Measures: green=micrometric, blue=interferometric, purple=photographic