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Ernie Ostuno
December 25th, 2019, 02:42 AM
I observed the open cluster King 6 in Camelopardalis many years ago, but recently came across an online reference that said it was the same cluster as OCL 381 from the Alter et al list of 1970. If so, there appears to be an error in the R.A. in Alter, which plots OCL 381 at about 3h 47m in R.A. (2000), while King 6 is at 3h 28m. Is this a known error? i checked the sky atlas and while there does appear to be a star cluster at 3h 28m, +56 27 the coordinates of King 6, there does not appear to be an obvious cluster at 3h 47m +56 27 the coordinates of OCL 381.

Has anyone heard of OCL 381 being given a wrong R.A. in the list of clusters in Alter et al?

Paul Alsing
December 26th, 2019, 06:53 PM
Well, for what it's worth, SkyTools show King 6 and OCL 381 as being the same object, located at R.A.: 03h28m06.0s Dec.: +56°27'00"...

obrazell
December 27th, 2019, 09:04 AM
Interestingly DSP 7 shows King 6 as OCL 169 and OCL 381 as Czernik 24 in Orion :-) . Looks like some interesting issues with the OCL listing (or what version people use). AstroPlanner would agree with SkyTools on this one

Owen

obrazell
December 27th, 2019, 12:00 PM
Scratch that last one as I understand it now. SkyTools and others uses the 1970 Alter catalogue and gives the running number there whereas DSP 7 uses the Optically Visible Open Clusters Catalog (Dias+, 2002-2012) and has an OCL number again based on the running number which are of course not the same even though it uses OCL as the catalogue.

Owen