01084-5515 RST1205AB (Zet Phe)

Coord 2000	01084-5515		Discov num	RST1205		Comp	AB		Coord arcsec 2000	01 08 23.08 -55 14 44.7
Date first	1931		Date last	2017		Obs	28
Pa first	22		Pa last	122		P.A. Now (θ)	129.7°
Sep first	0.6		Sep last	0.6		Sep. Now (ρ)	0.51"
Mag pri	4.02		Mag sec	6.80		delta mag (ΔM)	2.78		Spectral class	B6V+B9V (blue-white/blue-white)
Pri motion ra	+010		Sec motion ra
Pri motion dec	+016		Sec motion dec
Notes	N O (See Notes, 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	Zet Phe	232306	01084-5515	RST1205	AB	1931	2017	28	130	0.5	4.02	6.80	2.78	Y	<===
Show		232306	01084-5515	RMK 2	AB,C	1835	2016	42	239	6.8	4.00	8.23	4.23

Triple system
4 visible stars in this system

Precise pa	122.1		Precise sep	0.57		Name	Zet Phe		Constellation	Phoenix
SAO	232306		HIP	5348		Tycho2	8476-01302-1		Gaia DR2	4913847589156808960
HD	6882		HR	338		GC	1387		CD	CD-55 267
CP	CP-55 241		Bayer	Zeta Phoenicis		Bayer name	Zet Phe		Distance	91.58
Distance ly	298.73		last precise pa	122.1		last precise sep	0.57

Period (P)	210.37y	± 61.4	Periastron (T)	2122.81y	± 0.4	Semi-major axis (a)	0.804a	± 0.132
Eccentricity (e)	0.348	± 0.17	Inclination (i)	61.9°	± 3.7	Longitude of periastron (ω)	271.7°	± 23.5
Node (Ω)	33.5°	± 9.3	Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	1999

label rho theta 2000 0.550 95.5 2001 0.545 97.1 2002 0.541 98.8 2003 0.537 100.5 2004 0.533 102.2 2005 0.529 103.9 2006 0.526 105.7 2007 0.523 107.4 2008 0.520 109.2 2009 0.518 111.0 2010 0.515 112.9 2011 0.514 114.7 2012 0.512 116.6 2013 0.511 118.4 2014 0.511 120.3 2015 0.510 122.2 2016 0.510 124.1 2017 0.511 125.9 2018 0.512 127.8 2019 0.513 129.7 2020 0.514 131.5 2021 0.516 133.4 2022 0.518 135.2 2023 0.521 137.0 2024 0.524 138.8 2025 0.527 140.6 2026 0.530 142.3 2027 0.534 144.0 2028 0.538 145.7 2029 0.542 147.4 2030 0.547 149.1 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
01084-5515	RST1205	AB	2007	13	108	0.5	4.02	6.80	B6V+B9V	NOD	010823.08-551444.7
01084-5515	RST1205	AB	2008	14	109	0.5	4.02	6.80	B6V+B9V	NOD	010823.08-551444.7
01084-5515	RST1205	AB	2009	16	110	0.5	4.02	6.80	B6V+B9V	NOD	010823.08-551444.7
01084-5515	RST1205	AB	2011	19	113	0.6	4.02	6.80	B6V B9V	NOD	010823.08-551444.7
01084-5515	RST1205	AB	2015	21	118	0.6	4.02	6.80	B6V+B9V	NO	010823.08-551444.7
01084-5515	RST1205	AB	2017	28	122	0.6	4.02	6.80	B6V+B9V	NO	010823.08-551444.7

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