Coord 2000	00572+2325	Discov num	MKT 2	Comp	Aa,Ab	Coord arcsec 2000	00 57 12.43 +23 25 03.9
Date first	1990	Date last	1992	Obs	23
Pa first	157	Pa last	41	P.A. Now (θ)	41°
Sep first	0.0	Sep last	0.0	Sep. Now (ρ)	0"
Mag pri	4.42	Mag sec		delta mag (ΔM)		Spectral class	G8IIIb (yellow)
Pri motion ra	-044	Sec motion ra
Pri motion dec	-045	Sec motion dec
Notes	N O (See Notes, Orbital solution)

This double is physical.

00572+2325 SYSTEM COMPONENTS

Show

name

SAO

coord_2000

discov#

comp

first

last

obs

sep

mag1

mag2

d_mag

orb

current

Show

74388

00572+2325

MKT 2

Aa,Ab

1990

1992

0.0

4.42

<===

Show

Eta And

74388

00572+2325

FOX 116

1894

2001

232

129.3

4.42

12.34

7.92

Triple system
2 visible stars in this system

OTHER CATALOGS AND DESIGNATIONS

Precise pa	40.5	Precise sep	0.01	Constellation	Andromeda	SAO	74388
HIP	4463	Tycho2	1740-02109-1	Gaia DR2	2803727059958899584	HD	5516
HR	271	GC	1136	BD	BD+22 153	Bayer	Eta Andromedae
Bayer name	Eta And	Flamsteed	38 Andromedae	Flamsteed name	38 And	Distance	70.42
Distance ly	229.71	last precise pa	40.5	last precise sep	0.01

ORBITAL ELEMENTS

Period (P)	115.72d	± 0.01	Periastron (T)	48013d (1990.331y)	± 1	Semi-major axis (a)	10.37m	± 0.03
Eccentricity (e)	0.006	± 0.002	Inclination (i)	30.5°	± 0.4	Longitude of periastron (ω)	215°	± 4
Node (Ω)	69.4°	± 0.5	Note			Grade	1	(1=Definitive, 9=Indet.)
Equinox			Last observation	1992

label	rho	theta
2000-01-01	0.010	106.6
2001-01-01	0.009	167.6
2002-01-01	0.010	226.0
2003-01-01	0.010	276.0
2004-01-01	0.009	335.9
2005-01-01	0.010	36.7
2006-01-01	0.010	86.0
2007-01-01	0.009	141.9
2008-01-01	0.010	204.4
2009-01-01	0.010	255.8
2010-01-01	0.009	310.2
2011-01-01	0.009	14.2
2012-01-01	0.010	66.7
2013-01-01	0.010	117.7
2014-01-01	0.009	180.4
2015-01-01	0.010	236.1
2016-01-01	0.010	286.8
2017-01-01	0.009	349.1
2018-01-01	0.010	47.1
2019-01-01	0.010	96.1
2020-01-01	0.009	154.7
2021-01-01	0.010	215.5
2022-01-01	0.010	265.8
2023-01-01	0.009	322.9
2024-01-01	0.010	25.8
2025-01-01	0.010	76.4
2026-01-01	0.009	129.5
2027-01-01	0.009	192.8
2028-01-01	0.010	246.0
2029-01-01	0.009	298.2
2030-01-01	0.009	1.9

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

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

WDS HISTORIC DATA

coord_2000	discov_num	comp	epoch	obs	pa	sep	mag_pri	mag_sec	spectr	notes	coord_arcsec_2000
00572+2325	MKT 2	Aa,Ab	1992	23	41	0.0	4.42		G8IIIb	NO	005712.43+232503.9

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