21520+5548 STF 2840 AB (NSV13909)

21^h 52^m 01.02^s +55° 47' 48.3" P.A. 197.00 sep 17.6 mag 5.64,6.42 Sp B6IV-V dist. 460.83 pc (1503.23 l.y.)

Coord 2000	21520+5548	Discov num	STF2840	Comp	AB	Coord arcsec 2000	21 52 01.02 +55 47 48.3
Date first	1782	Date last	2024	Obs	112
Pa first	192	Pa last	196.5	P.A. Now (θ)	196.5°
Sep first	21.1	Sep last	17.64	Sep. Now (ρ)	17.64"
Mag pri	5.64	Mag sec	6.42	delta mag (ΔM)	0.78	Spectral class	B6IV-V (blue-white)
Pri motion ra	+019	Sec motion ra	+013
Pri motion dec	-001	Sec motion dec	+013
Notes	N L U (See Notes, Linear solution, Proper motion indicates non-physical)

rPM=0.801

This double is not physical.

21520+5548 SYSTEM COMPONENTS

Triple system
3 estimated visually detectable stars in this system

OTHER CATALOGS AND DESIGNATIONS