18443+3940 STF2382AB (Eps1 Lyr)

Coord 2000	18443+3940		Discov num	STF2382		Comp	AB		Coord arcsec 2000	18 44 20.34 +39 40 12.4
Date first	1777		Date last	2020		Obs	640
Pa first	45		Pa last	345		P.A. Now (θ)	344.2°
Sep first	4.0		Sep last	2.2		Sep. Now (ρ)	2.3"
Mag pri	5.15		Mag sec	6.10		delta mag (ΔM)	0.95		Spectral class	A4V+F1V (white/yellow-white)
Pri motion ra	+011		Sec motion ra	+002
Pri motion dec	+061		Sec motion dec	+047
Notes	N O (See Notes, Orbital solution)

rPM=0.269 (< 0.3, Physical double) This double is physical.

Show	name	SAO	coord_2000	discov#	comp	first	last	obs	pa	sep	mag1	mag2	d_mag	orb	current
Show	Eps1 Lyr	67310	18443+3940	STF2382	AB	1777	2020	640	344	2.3	5.15	6.10	0.95	Y	<===
Show	Double Double	67310	18443+3940	STFA 37	AB,CD	1830	2016	97	172	209.5	4.67	4.56	0.11
Show		67310	18443+3940	STFA 37	AD	1903	2017	18	172	210.5	5.15	5.38	0.23
Show		67310	18443+3940	STFA 37	AI	1863	2015	23	137	149.5	5.15	10.12	4.97
Show		67310	18443+3940	STFA 37	BC	1903	2011	14	172	210.9	6.10	5.25	0.85
Show		67310	18443+3940	STFA 37	BD	1903	2000	11	172	209.6	6.10	5.38	0.72
Show		67310	18443+3940	STFA 37	BI	1872	2015	10	137	151.3	6.10	10.12	4.02
Show		67315	18443+3940	CHR 77	Ca,Cb	1985	2005	5	43	0.2	5.25			Y
Show		67315	18443+3940	STF2383	CD	1777	2020	637	74	2.4	5.25	5.38	0.13	Y
Show		67315	18443+3940	SHJ 277	CD,F	2002	2015	3	0	93.3	4.56	12.70	8.14
Show		67315	18443+3940	SHJ 277	CD,G	2000	2015	4	293	75.1	4.56	14.20	9.64
Show		67315	18443+3940	SHJ 277	CD,H	2000	2015	4	313	95.7	4.56	13.90	9.34
Show		67315	18443+3940	STF2383	CE	2000	2015	8	334	63.2	5.25	12.30	7.05
Show		67315	18443+3940	STFA 37	CI	1863	2012	18	37	120.4	5.25	10.12	4.87
Show		67315	18443+3940	STFA 37	DI	1909	2000	6	37	121.6	5.38	10.12	4.74
Show		67315	18443+3940	SHJ 277	EF	1831	2015	15	37	45.6	12.30	12.70	0.40
Show		67315	18443+3940	SHJ 277	EG	1878	2015	11	236	50.0	12.30	14.20	1.90
Show		67315	18443+3940	STFA 37	EI	2000	2015	7	68	108.9	12.30	10.12	2.18
Show		67315	18443+3940	SHJ 277	GH	1878	2015	13	358	35.8	14.20	13.90	0.30

11-fold system
11 visible stars in this system

Precise pa	345.1		Precise sep	2.19		Name	Eps1 Lyr		Constellation	Lyra
SAO	67310		HIP	91919		Tycho2	3122-03438-2		Gaia DR2	2098237660363229312
HD	173582		HR	7051		GC	25667		ADS	11635
BD	BD+39 3509		Bayer	Epsilon 1 Lyrae		Bayer name	Eps1 Lyr		Flamsteed	4 Lyrae
Flamsteed name	4 Lyr		Distance	49.78		Distance ly	162.38		last precise pa	345.1
last precise sep	2.19

Period (P)	1725y		Periastron (T)	190y		Semi-major axis (a)	4.17a
Eccentricity (e)	0.243		Inclination (i)	118.6°		Longitude of periastron (ω)	198°
Node (Ω)	198°		Note			Grade	4	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	2003

label rho theta 2000 2.468 350.4 2001 2.460 350.1 2002 2.452 349.9 2003 2.444 349.6 2004 2.436 349.3 2005 2.428 349.0 2006 2.419 348.7 2007 2.411 348.4 2008 2.403 348.1 2009 2.395 347.8 2010 2.387 347.5 2011 2.378 347.2 2012 2.370 347.0 2013 2.362 346.7 2014 2.354 346.3 2015 2.346 346.0 2016 2.337 345.7 2017 2.329 345.4 2018 2.321 345.1 2019 2.313 344.8 2020 2.305 344.5 2021 2.296 344.2 2022 2.288 343.8 2023 2.280 343.5 2024 2.272 343.2 2025 2.264 342.9 2026 2.256 342.5 2027 2.248 342.2 2028 2.240 341.9 2029 2.231 341.5 2030 2.223 341.2		Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.
		Measures: green=micrometric, blue=interferometric, purple=photographic

Period (P)	2802.8y		Periastron (T)	2051.49y		Semi-major axis (a)	14.237a
Eccentricity (e)	0.953		Inclination (i)	102.2°		Longitude of periastron (ω)	258.8°
Node (Ω)	149.6°		Note			Grade	4	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	2020

label rho theta 2000 2.484 350.3 2001 2.472 350.0 2002 2.460 349.7 2003 2.448 349.5 2004 2.436 349.2 2005 2.423 348.9 2006 2.410 348.6 2007 2.396 348.3 2008 2.382 348.0 2009 2.368 347.7 2010 2.353 347.4 2011 2.338 347.1 2012 2.323 346.8 2013 2.307 346.5 2014 2.290 346.2 2015 2.273 345.9 2016 2.255 345.6 2017 2.237 345.2 2018 2.218 344.9 2019 2.198 344.5 2020 2.178 344.2 2021 2.157 343.8 2022 2.135 343.5 2023 2.112 343.1 2024 2.088 342.7 2025 2.064 342.3 2026 2.038 341.9 2027 2.011 341.5 2028 1.983 341.1 2029 1.953 340.7 2030 1.922 340.3		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
18443+3940	STF2382	AB	2007	558	349	2.3	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2008	563	348	2.3	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2009	566	348	2.4	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2010	581	347	2.3	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2011	588	349	2.4	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2012	590	347	2.2	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2013	599	346	2.3	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2014	588	346	2.2	5.15	6.10	A4V F1V	NOD	184420.34+394012.4
18443+3940	STF2382	AB	2015	600	346	2.4	5.15	6.10	A4V+F1V	NO	184420.34+394012.4
18443+3940	STF2382	AB	2016	615	346	2.3	5.15	6.10	A4V+F1V	NO	184420.34+394012.4
18443+3940	STF2382	AB	2017	619	346	2.3	5.15	6.10	A4V+F1V	NO	184420.34+394012.4
18443+3940	STF2382	AB	2018	621	346	2.2	5.15	6.10	A4V+F1V	NO	184420.34+394012.4
18443+3940	STF2382	AB	2019	628	345	2.2	5.15	6.10	A4V+F1V	NO	184420.34+394012.4

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