01541-7729 JSP  31

Coord 2000	01541-7729		Discov num	JSP  31		Comp			Coord arcsec 2000	01 54 06.06 -77 29 28.5
Date first	1929		Date last	2016		Obs	8
Pa first	354		Pa last	52		P.A. Now (θ)	49.4°
Sep first	0.2		Sep last	0.3		Sep. Now (ρ)	0.34"
Mag pri	7.55		Mag sec	8.25		delta mag (ΔM)	0.7		Spectral class	A8IV/V (white)
Pri motion ra	+012		Sec motion ra
Pri motion dec	+039		Sec motion dec
Notes	N O (See Notes, Orbital solution)

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

Precise pa	52.2		Precise sep	0.311		Constellation	Hydrus		SAO	255831
HIP	8866		Tycho2	9352-01737-1		HD	12121		CP	CP-78 40
Distance	147.93		Distance ly	482.55		last precise pa	52.2		last precise sep	0.311

Period (P)	250y		Periastron (T)	1968.23y		Semi-major axis (a)	0.43a
Eccentricity (e)	0.5		Inclination (i)	112.1°		Longitude of periastron (ω)	180.1°
Node (Ω)	25.5°		Note			Grade	5	(1=Definitive, 9=Indet.)
Equinox	2000		Last observation	2016

label rho theta 2000 0.162 81.3 2001 0.170 78.1 2002 0.178 75.3 2003 0.187 72.7 2004 0.195 70.3 2005 0.204 68.1 2006 0.213 66.1 2007 0.222 64.3 2008 0.231 62.6 2009 0.240 61.1 2010 0.250 59.6 2011 0.259 58.3 2012 0.268 57.0 2013 0.277 55.8 2014 0.286 54.7 2015 0.294 53.7 2016 0.303 52.7 2017 0.312 51.8 2018 0.321 51.0 2019 0.329 50.1 2020 0.338 49.4 2021 0.346 48.6 2022 0.354 47.9 2023 0.362 47.2 2024 0.371 46.6 2025 0.378 46.0 2026 0.386 45.4 2027 0.394 44.8 2028 0.402 44.3 2029 0.409 43.7 2030 0.417 43.2 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
01541-7729	JSP 31		1991	7	122	0.1	7.55	8.25	A8IV/V	N	015406.06-772928.5
01541-7729	JSP 31		2016	8	52	0.3	7.55	8.25	A8IV/V	NO	015406.06-772928.5

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