Used acronyms: NEML=Naked Eye Magnitude Limit, SQM=Sky Quality Meter, TML=Telescope Magnitude Limit, CO=Central Obstruction, delta_m=difference in magnitudes between double star components, RoT=Rule of Thumb, pD_mm=proposed D_mm for resolving a binary (ident with earlier used pA=proposed Aperture), D_mm=Diameter (of scope) in mm, UCAC4=USNO CCD Astrograph Catalog 4th edition
Roberto Botero, Kent, UK
Quote:I found this relatively new (2010) academic paper ( 5 Equ )on the properties of the main star in the 5 Equ system in a search in the Los Alamos Lab online archive. The paper deals mostly with its magnetic properties - as 5 Equ is one of the brightest stars with high frequency magnetic field changes visible in the sky. It lists its current multiple system separation as 1.25" +- 0.04" citing another paper of 2002. If that is indeed the separation, it should be easily visible with a 5-6" instrument under good conditions.What do you think?
David Cotterell Toronto, Ontario "If an observer actually sees an object, there is no point in referring to a formula to find out whether he ought to see it; and if he fails to detect it, no formula will ensure his success." - W.H. Steavenson 8" f/15.5 TEC Maksutov 16" f/5 Teeter/Zambuto Dob 66mm WO SD AT 65EDQ APO Refractor Astro-Physics Mach 1 GTO Mount iOptron ZEQ25 mount Canon 60Da
WO Megrez 90, Vixen Sphinx Deluxe + NexSXD, Nikon D7100, ZWO ASI120MM StelleDoppie - Double Star Database
DJ Eastern Missouri, USA Bushnell 8x42's, SV80ed, Nexstar 130SLT, C5+, 8" LX200 Classic, 10" f/7 Cave, Orion XT10 w/Moonlite focuser