19450+4508 STF2579AB (Del Cyg)

Coord 2000	19450+4508		Discov num	STF2579		Comp	AB		Coord arcsec 2000	19 44 58.44 +45 07 50.5
Date first	1826		Date last	2017		Obs	487
Pa first	41		Pa last	215		P.A. Now (θ)	214.8°
Sep first	1.9		Sep last	2.7		Sep. Now (ρ)	2.77"
Mag pri	2.89		Mag sec	6.27		delta mag (ΔM)	3.38		Spectral class	B9.5IV (blue-white)
Pri motion ra	+051		Sec motion ra
Pri motion dec	+050		Sec motion dec
Notes	N O (See Notes, Orbital solution)

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

Show	name	SAO	coord_2000	discov#	comp	first	last	obs	pa	sep	mag1	mag2	d_mag	orb	current
Show	Del Cyg	48796	19450+4508	STF2579	AB	1826	2017	487	215	2.8	2.89	6.27	3.38	Y	<===
Show		48796	19450+4508	STF2579	AC	1913	2017	8	67	62.5	2.89	12.00	9.11
Show		48796	19450+4508	DAL 37	AD	1998	2007	3	246	42.0	2.89	14.80	11.91
Show		48796	19450+4508	DAL 37	AF	1998	2007	3	66	147.5	2.89	12.80	9.91
Show		48796	19450+4508	DAL 37	DE	1998	2015	4	251	3.5	14.80	15.20	0.40
Show		48796	19450+4508	DAL 37	FG	2007	2015	2	312	3.1	13.00	13.80	0.80

Septuple system
7 visible stars in this system

Precise pa	215.2		Precise sep	2.68		Name	Del Cyg		Constellation	Cygnus
SAO	48796		HIP	97165		Tycho2	3557-02486-1		Gaia DR2	87999414656
HD	186882		HR	7528		GC	27347		ADS	12880
BD	BD+44 3234		Bayer	Delta Cygni		Bayer name	Del Cyg		Flamsteed	18 Cygni
Flamsteed name	18 Cyg		Distance	50.58		Distance ly	164.99		last precise pa	215.2
last precise sep	2.68

Period (P)	657.1722y	± 204.03	Periastron (T)	1866.357y	± 15.4645	Semi-major axis (a)	2.68872a	± 0.43688
Eccentricity (e)	0.43962	± 0.07552	Inclination (i)	154.254°	± 6.254	Longitude of periastron (ω)	151.114°	± 9.365
Node (Ω)	138.595°	± 31.21	Note			Grade	4	(1=Definitive, 9=Indet.)
Equinox			Last observation	2015

label rho theta 2000 2.574 223.8 2001 2.584 223.4 2002 2.594 222.9 2003 2.604 222.4 2004 2.614 221.9 2005 2.623 221.5 2006 2.633 221.0 2007 2.643 220.5 2008 2.652 220.1 2009 2.662 219.6 2010 2.672 219.2 2011 2.682 218.7 2012 2.691 218.3 2013 2.701 217.8 2014 2.710 217.4 2015 2.720 217.0 2016 2.730 216.5 2017 2.739 216.1 2018 2.749 215.7 2019 2.758 215.3 2020 2.767 214.8 2021 2.777 214.4 2022 2.786 214.0 2023 2.796 213.6 2024 2.805 213.2 2025 2.814 212.8 2026 2.824 212.4 2027 2.833 212.0 2028 2.842 211.6 2029 2.851 211.2 2030 2.861 210.8 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
19450+4508	STF2579	AB	2007	439	222	2.5	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2008	445	220	2.8	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2010	451	220	2.7	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2011	454	216	2.5	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2013	461	218	2.5	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2014	469	218	2.6	2.89	6.27	B9.5IV	NOD	194458.44+450750.5
19450+4508	STF2579	AB	2015	472	217	2.7	2.89	6.27	B9.5IV	NO	194458.44+450750.5
19450+4508	STF2579	AB	2016	481	215	2.7	2.89	6.27	B9.5IV	NO	194458.44+450750.5
19450+4508	STF2579	AB	2017	487	215	2.7	2.89	6.27	B9.5IV	NO	194458.44+450750.5

If you need more information about this double, apply for a data request form to the WDS.